4536 lines
113 KiB
JavaScript
4536 lines
113 KiB
JavaScript
//! mingo.js 2.5.3
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//! Copyright (c) 2020 Francis Asante
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//! MIT
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// Javascript native types
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const T_NULL = 'null';
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const T_UNDEFINED = 'undefined';
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const T_BOOL = 'bool';
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const T_BOOLEAN = 'boolean';
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const T_NUMBER = 'number';
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const T_STRING = 'string';
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const T_DATE = 'date';
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const T_REGEX = 'regex';
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const T_REGEXP = 'regexp';
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const T_ARRAY = 'array';
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const T_OBJECT = 'object';
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const T_FUNCTION = 'function';
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// no array, object, or function types
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const JS_SIMPLE_TYPES = [T_NULL, T_UNDEFINED, T_BOOLEAN, T_NUMBER, T_STRING, T_DATE, T_REGEXP];
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// operator classes
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const OP_EXPRESSION = 'expression';
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const OP_GROUP = 'group';
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const OP_PIPELINE = 'pipeline';
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const OP_PROJECTION = 'projection';
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const OP_QUERY = 'query';
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const MISSING = () => {};
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/**
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* Utility functions
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*/
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// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/includes
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if (!Array.prototype.includes) {
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Object.defineProperty(Array.prototype, 'includes', {
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value: function(valueToFind, fromIndex) {
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if (this == null) {
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throw new TypeError('"this" is null or not defined');
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}
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// 1. Let O be ? ToObject(this value).
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var o = Object(this);
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// 2. Let len be ? ToLength(? Get(O, "length")).
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var len = o.length >>> 0;
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// 3. If len is 0, return false.
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if (len === 0) {
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return false;
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}
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// 4. Let n be ? ToInteger(fromIndex).
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// (If fromIndex is undefined, this step produces the value 0.)
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var n = fromIndex | 0;
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// 5. If n ≥ 0, then
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// a. Let k be n.
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// 6. Else n < 0,
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// a. Let k be len + n.
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// b. If k < 0, let k be 0.
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var k = Math.max(n >= 0 ? n : len - Math.abs(n), 0);
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function sameValueZero(x, y) {
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return x === y || (typeof x === 'number' && typeof y === 'number' && isNaN(x) && isNaN(y));
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}
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// 7. Repeat, while k < len
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while (k < len) {
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// a. Let elementK be the result of ? Get(O, ! ToString(k)).
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// b. If SameValueZero(valueToFind, elementK) is true, return true.
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if (sameValueZero(o[k], valueToFind)) {
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return true;
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}
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// c. Increase k by 1.
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k++;
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}
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// 8. Return false
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return false;
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}
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});
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}
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const arrayPush = Array.prototype.push;
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function assert (condition, message) {
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if (!condition) err(message);
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}
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/**
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* Deep clone an object
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*/
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function cloneDeep (obj) {
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switch (jsType(obj)) {
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case T_ARRAY: return obj.map(cloneDeep)
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case T_OBJECT: return objectMap(obj, cloneDeep)
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default: return obj
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}
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}
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/**
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* Shallow clone an object
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*/
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function clone (obj) {
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switch (jsType(obj)) {
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case T_ARRAY:
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return into([], obj)
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case T_OBJECT:
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return Object.assign({}, obj)
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default:
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return obj
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}
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}
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function getType (v) {
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if (v === null) return 'Null'
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if (v === undefined) return 'Undefined'
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return v.constructor.name
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}
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function jsType (v) { return getType(v).toLowerCase() }
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function isBoolean (v) { return jsType(v) === T_BOOLEAN }
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function isString (v) { return jsType(v) === T_STRING }
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function isNumber (v) { return jsType(v) === T_NUMBER }
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const isArray = Array.isArray || (v => !!v && v.constructor === Array);
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function isObject(v) { return !!v && v.constructor === Object }
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function isObjectLike (v) { return v === Object(v) } // objects, arrays, functions, date, custom object
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function isDate (v) { return jsType(v) === T_DATE }
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function isRegExp (v) { return jsType(v) === T_REGEXP }
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function isFunction (v) { return jsType(v) === T_FUNCTION }
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function isNil (v) { return v === null || v === undefined }
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function isNull (v) { return v === null }
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function isUndefined (v) { return v === undefined }
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function inArray (arr, item) { return arr.includes(item) }
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function notInArray (arr, item) { return !inArray(arr, item) }
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function truthy (arg) { return !!arg }
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function isEmpty (x) {
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return isNil(x) ||
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isArray(x) && x.length === 0 ||
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isObject(x) && keys(x).length === 0 || !x
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}
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// ensure a value is an array
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function ensureArray (x) { return isArray(x) ? x : [x] }
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function has (obj, prop) { return obj.hasOwnProperty(prop) }
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function err (s) { throw new Error(s) }
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const keys = Object.keys;
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// ////////////////// UTILS ////////////////////
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/**
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* Iterate over an array or object
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* @param {Array|Object} obj An object-like value
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* @param {Function} fn The callback to run per item
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* @param {*} ctx The object to use a context
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* @return {void}
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*/
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function each (obj, fn, ctx) {
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fn = fn.bind(ctx);
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if (isArray(obj)) {
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for (let i = 0, len = obj.length; i < len; i++) {
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if (fn(obj[i], i, obj) === false) break
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}
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} else {
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for (let k in obj) {
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if (obj.hasOwnProperty(k)) {
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if (fn(obj[k], k, obj) === false) break
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}
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}
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}
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}
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/**
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* Transform values in an object
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*
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* @param {Object} obj An object whose values to transform
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* @param {Function} fn The transform function
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* @param {*} ctx The value to use as the "this" context for the transform
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* @return {Array|Object} Result object after applying the transform
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*/
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function objectMap (obj, fn, ctx) {
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fn = fn.bind(ctx);
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let o = {};
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let objKeys = keys(obj);
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for (let i = 0; i < objKeys.length; i++) {
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let k = objKeys[i];
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o[k] = fn(obj[k], k);
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}
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return o
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}
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/**
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* Deep merge objects or arrays.
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* When the inputs have unmergeable types, the source value (right hand side) is returned.
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* If inputs are arrays of same length and all elements are mergable, elements in the same position are merged together.
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* If any of the elements are unmergeable, elements in the source are appended to the target.
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* @param target {Object|Array} the target to merge into
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* @param obj {Object|Array} the source object
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*/
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function merge(target, obj, opt = {}) {
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// take care of missing inputs
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if (target === MISSING) return obj
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if (obj === MISSING) return target
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const inputs = [target, obj];
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if (!(inputs.every(isObject) || inputs.every(isArray))) {
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throw Error('mismatched types. must both be array or object')
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}
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// default options
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opt.flatten = opt.flatten || false;
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if (isArray(target)) {
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if (opt.flatten) {
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let i = 0;
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let j = 0;
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while (i < target.length && j < obj.length) {
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target[i] = merge(target[i++], obj[j++], opt);
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}
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while (j < obj.length) {
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target.push(obj[j++]);
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}
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} else {
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arrayPush.apply(target, obj);
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}
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} else {
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Object.keys(obj).forEach((k) => {
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if (target.hasOwnProperty(k)) {
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target[k] = merge(target[k], obj[k], opt);
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} else {
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target[k] = obj[k];
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}
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});
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}
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return target
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}
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/**
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* Reduce any array-like object
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* @param collection
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* @param fn
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* @param accumulator
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* @returns {*}
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*/
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function reduce (collection, fn, accumulator) {
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if (isArray(collection)) return collection.reduce(fn, accumulator)
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// array-like objects
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each(collection, (v, k) => accumulator = fn(accumulator, v, k, collection));
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return accumulator
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}
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/**
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* Returns the intersection between two arrays
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*
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* @param {Array} xs The first array
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* @param {Array} ys The second array
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* @return {Array} Result array
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*/
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function intersection (xs, ys) {
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let hashes = ys.map(hashCode);
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return xs.filter(v => inArray(hashes, hashCode(v)))
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}
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/**
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* Returns the union of two arrays
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*
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* @param {Array} xs The first array
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* @param {Array} ys The second array
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* @return {Array} The result array
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*/
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function union (xs, ys) {
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return into(into([], xs), ys.filter(notInArray.bind(null, xs)))
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}
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/**
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* Flatten the array
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*
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* @param {Array} xs The array to flatten
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* @param {Number} depth The number of nested lists to iterate
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*/
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function flatten (xs, depth = -1) {
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let arr = [];
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function flatten2(ys, iter) {
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for (let i = 0, len = ys.length; i < len; i++) {
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if (isArray(ys[i]) && (iter > 0 || iter < 0)) {
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flatten2(ys[i], Math.max(-1, iter - 1));
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} else {
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arr.push(ys[i]);
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}
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}
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}
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flatten2(xs, depth);
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return arr
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}
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/**
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* Unwrap a single element array to specified depth
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* @param {Array} arr
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* @param {Number} depth
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*/
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function unwrap(arr, depth) {
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if (depth < 1) return arr
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while (depth-- && isArray(arr) && arr.length === 1) arr = arr[0];
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return arr
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}
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/**
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* Determine whether two values are the same or strictly equivalent
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*
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* @param {*} a The first value
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* @param {*} b The second value
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* @return {Boolean} Result of comparison
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*/
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function isEqual (a, b) {
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let lhs = [a];
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let rhs = [b];
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while (lhs.length > 0) {
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a = lhs.pop();
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b = rhs.pop();
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// strictly equal must be equal.
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if (a === b) continue
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// unequal types and functions cannot be equal.
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let type = jsType(a);
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if (type !== jsType(b) || type === T_FUNCTION) return false
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// leverage toString for Date and RegExp types
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switch (type) {
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case T_ARRAY:
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if (a.length !== b.length) return false
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//if (a.length === b.length && a.length === 0) continue
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into(lhs, a);
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into(rhs, b);
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break
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case T_OBJECT:
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// deep compare objects
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let ka = keys(a);
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let kb = keys(b);
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// check length of keys early
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if (ka.length !== kb.length) return false
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// we know keys are strings so we sort before comparing
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ka.sort();
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kb.sort();
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// compare keys
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for (let i = 0, len = ka.length; i < len; i++) {
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let temp = ka[i];
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if (temp !== kb[i]) {
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return false
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} else {
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// save later work
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lhs.push(a[temp]);
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rhs.push(b[temp]);
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}
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}
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break
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default:
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// compare encoded values
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if (encode(a) !== encode(b)) return false
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}
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}
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return lhs.length === 0
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}
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/**
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* Return a new unique version of the collection
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* @param {Array} xs The input collection
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* @return {Array} A new collection with unique values
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*/
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function unique (xs) {
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let h = {};
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let arr = [];
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each(xs, (item) => {
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let k = hashCode(item);
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if (!has(h, k)) {
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arr.push(item);
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h[k] = 0;
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}
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});
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return arr
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}
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/**
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* Encode value to string using a simple non-colliding stable scheme.
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*
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* @param value
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* @returns {*}
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*/
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function encode (value) {
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let type = jsType(value);
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switch (type) {
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case T_BOOLEAN:
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case T_NUMBER:
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case T_REGEXP:
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return value.toString()
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case T_STRING:
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return JSON.stringify(value)
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case T_DATE:
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return value.toISOString()
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case T_NULL:
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case T_UNDEFINED:
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return type
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case T_ARRAY:
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return '[' + value.map(encode) + ']'
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default:
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let prefix = (type === T_OBJECT)? '' : `${getType(value)}`;
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let objKeys = keys(value);
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objKeys.sort();
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return `${prefix}{` + objKeys.map(k => `${encode(k)}:${encode(value[k])}`) + '}'
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}
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}
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/**
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* Generate hash code
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* This selected function is the result of benchmarking various hash functions.
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* This version performs well and can hash 10^6 documents in ~3s with on average 100 collisions.
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*
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* @param value
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* @returns {*}
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*/
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function hashCode (value) {
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if (isNil(value)) return null
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let hash = 0;
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let s = encode(value);
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let i = s.length;
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while (i) hash = ((hash << 5) - hash) ^ s.charCodeAt(--i);
|
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return hash >>> 0
|
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}
|
||
|
||
/**
|
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* Default compare function
|
||
* @param {*} a
|
||
* @param {*} b
|
||
*/
|
||
function compare (a, b) {
|
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if (a < b) return -1
|
||
if (a > b) return 1
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||
return 0
|
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}
|
||
|
||
/**
|
||
* Returns a (stably) sorted copy of list, ranked in ascending order by the results of running each value through iteratee
|
||
*
|
||
* This implementation treats null/undefined sort keys as less than every other type
|
||
*
|
||
* @param {Array} collection
|
||
* @param {Function} fn The function used to resolve sort keys
|
||
* @param {Function} cmp The comparator function to use for comparing values
|
||
* @return {Array} Returns a new sorted array by the given iteratee
|
||
*/
|
||
function sortBy (collection, fn, cmp) {
|
||
let sorted = [];
|
||
let result = [];
|
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let hash = {};
|
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cmp = cmp || compare;
|
||
|
||
if (isEmpty(collection)) return collection
|
||
|
||
for (let i = 0; i < collection.length; i++) {
|
||
let obj = collection[i];
|
||
let key = fn(obj, i);
|
||
|
||
// objects with nil keys will go in first
|
||
if (isNil(key)) {
|
||
result.push(obj);
|
||
} else {
|
||
if (hash[key]) {
|
||
hash[key].push(obj);
|
||
} else {
|
||
hash[key] = [obj];
|
||
}
|
||
sorted.push(key);
|
||
}
|
||
}
|
||
|
||
// use native array sorting but enforce stableness
|
||
sorted.sort(cmp);
|
||
|
||
for (let i = 0; i < sorted.length; i++) {
|
||
into(result, hash[sorted[i]]);
|
||
}
|
||
|
||
return result
|
||
}
|
||
|
||
/**
|
||
* Groups the collection into sets by the returned key
|
||
*
|
||
* @param collection
|
||
* @param fn {Function} to compute the group key of an item in the collection
|
||
* @returns {{keys: Array, groups: Array}}
|
||
*/
|
||
function groupBy (collection, fn) {
|
||
let result = {
|
||
'keys': [],
|
||
'groups': []
|
||
};
|
||
let lookup = {};
|
||
each(collection, obj => {
|
||
let key = fn(obj);
|
||
let hash = hashCode(key);
|
||
let index = -1;
|
||
|
||
if (lookup[hash] === undefined) {
|
||
index = result.keys.length;
|
||
lookup[hash] = index;
|
||
result.keys.push(key);
|
||
result.groups.push([]);
|
||
}
|
||
index = lookup[hash];
|
||
result.groups[index].push(obj);
|
||
});
|
||
return result
|
||
}
|
||
|
||
/**
|
||
* Push elements in given array into target array
|
||
*
|
||
* @param {*} target The array to push into
|
||
* @param {*} xs The array of elements to push
|
||
*/
|
||
function into (target, xs) {
|
||
arrayPush.apply(target, xs);
|
||
return target
|
||
}
|
||
|
||
/**
|
||
* Find the insert index for the given key in a sorted array.
|
||
*
|
||
* @param {*} array The sorted array to search
|
||
* @param {*} item The search key
|
||
*/
|
||
function findInsertIndex (array, item) {
|
||
// uses binary search
|
||
let lo = 0;
|
||
let hi = array.length - 1;
|
||
while (lo <= hi) {
|
||
let mid = Math.round(lo + (hi - lo) / 2);
|
||
if (item < array[mid]) {
|
||
hi = mid - 1;
|
||
} else if (item > array[mid]) {
|
||
lo = mid + 1;
|
||
} else {
|
||
return mid
|
||
}
|
||
}
|
||
return lo
|
||
}
|
||
|
||
/**
|
||
* This is a generic memoization function
|
||
*
|
||
* This implementation uses a cache independent of the function being memoized
|
||
* to allow old values to be garbage collected when the memoized function goes out of scope.
|
||
*
|
||
* @param {*} fn The function object to memoize
|
||
*/
|
||
function memoize (fn) {
|
||
return ((memo) => {
|
||
return (...args) => {
|
||
let key = hashCode(args);
|
||
if (!has(memo, key)) {
|
||
memo[key] = fn.apply(this, args);
|
||
}
|
||
return memo[key]
|
||
}
|
||
})({/* storage */})
|
||
}
|
||
|
||
// mingo internal
|
||
|
||
/**
|
||
* Retrieve the value of a given key on an object
|
||
* @param obj
|
||
* @param field
|
||
* @returns {*}
|
||
* @private
|
||
*/
|
||
function getValue (obj, field) {
|
||
return isObjectLike(obj) ? obj[field] : undefined
|
||
}
|
||
|
||
/**
|
||
* Resolve the value of the field (dot separated) on the given object
|
||
* @param obj {Object} the object context
|
||
* @param selector {String} dot separated path to field
|
||
* @returns {*}
|
||
*/
|
||
function resolve (obj, selector, options = {}) {
|
||
let depth = 0;
|
||
|
||
// options
|
||
options.meta = options.meta || false;
|
||
|
||
function resolve2(o, path) {
|
||
let value = o;
|
||
for (let i = 0; i < path.length; i++) {
|
||
let field = path[i];
|
||
let isText = field.match(/^\d+$/) === null;
|
||
|
||
if (isText && isArray(value)) {
|
||
// On the first iteration, we check if we received a stop flag.
|
||
// If so, we stop to prevent iterating over a nested array value
|
||
// on consecutive object keys in the selector.
|
||
if (i === 0 && depth > 0) break
|
||
|
||
depth += 1;
|
||
path = path.slice(i);
|
||
|
||
value = reduce(value, (acc, item) => {
|
||
let v = resolve2(item, path);
|
||
if (v !== undefined) acc.push(v);
|
||
return acc
|
||
}, []);
|
||
break
|
||
} else {
|
||
value = getValue(value, field);
|
||
}
|
||
if (value === undefined) break
|
||
}
|
||
return value
|
||
}
|
||
|
||
obj = inArray(JS_SIMPLE_TYPES, jsType(obj)) ? obj : resolve2(obj, selector.split('.'));
|
||
return options.meta
|
||
? { result: obj, depth: depth }
|
||
: obj
|
||
}
|
||
|
||
/**
|
||
* Returns the full object to the resolved value given by the selector.
|
||
* This function excludes empty values as they aren't practically useful.
|
||
*
|
||
* @param obj {Object} the object context
|
||
* @param selector {String} dot separated path to field
|
||
*/
|
||
function resolveObj (obj, selector, options = {}) {
|
||
// options
|
||
options.preserveMissingValues = options.preserveMissingValues || false;
|
||
|
||
let names = selector.split('.');
|
||
let key = names[0];
|
||
// get the next part of the selector
|
||
let next = names.length === 1 || names.slice(1).join('.');
|
||
let isIndex = key.match(/^\d+$/) !== null;
|
||
let hasNext = names.length > 1;
|
||
let result;
|
||
let value;
|
||
|
||
try {
|
||
if (isArray(obj)) {
|
||
if (isIndex) {
|
||
result = getValue(obj, Number(key));
|
||
if (hasNext) {
|
||
result = resolveObj(result, next, options);
|
||
}
|
||
result = [result];
|
||
} else {
|
||
result = [];
|
||
each(obj, item => {
|
||
value = resolveObj(item, selector, options);
|
||
if (options.preserveMissingValues) {
|
||
if (value === undefined) {
|
||
value = MISSING;
|
||
}
|
||
result.push(value);
|
||
} else if (value !== undefined) {
|
||
result.push(value);
|
||
}
|
||
});
|
||
}
|
||
} else {
|
||
value = getValue(obj, key);
|
||
if (hasNext) {
|
||
value = resolveObj(value, next, options);
|
||
}
|
||
assert(value !== undefined);
|
||
result = {};
|
||
result[key] = value;
|
||
}
|
||
} catch (e) {
|
||
result = undefined;
|
||
}
|
||
|
||
return result
|
||
}
|
||
|
||
/**
|
||
* Filter out all MISSING values from the object in-place
|
||
* @param {*} obj The object the filter
|
||
*/
|
||
function filterMissing(obj) {
|
||
if (isArray(obj)) {
|
||
for (let i = obj.length - 1; i >= 0; i--) {
|
||
if (obj[i] === MISSING) {
|
||
obj.splice(i,1);
|
||
} else {
|
||
filterMissing(obj[i]);
|
||
}
|
||
}
|
||
} else if (isObject(obj)) {
|
||
for (let k in obj) {
|
||
if (obj.hasOwnProperty(k)) {
|
||
filterMissing(obj[k]);
|
||
}
|
||
}
|
||
}
|
||
return obj
|
||
}
|
||
|
||
/**
|
||
* Walk the object graph and execute the given transform function
|
||
* @param {Object|Array} obj The object to traverse
|
||
* @param {String} selector The selector
|
||
* @param {Function} fn Function to execute for value at the end the traversal
|
||
* @param {Boolean} force Force generating missing parts of object graph
|
||
* @return {*}
|
||
*/
|
||
function traverse (obj, selector, fn, force = false) {
|
||
let names = selector.split('.');
|
||
let key = names[0];
|
||
let next = names.length === 1 || names.slice(1).join('.');
|
||
|
||
if (names.length === 1) {
|
||
fn(obj, key);
|
||
} else {
|
||
// force the rest of the graph while traversing
|
||
if (force === true && isNil(obj[key])) {
|
||
obj[key] = {};
|
||
}
|
||
traverse(obj[key], next, fn, force);
|
||
}
|
||
}
|
||
|
||
/**
|
||
* Set the value of the given object field
|
||
*
|
||
* @param obj {Object|Array} the object context
|
||
* @param selector {String} path to field
|
||
* @param value {*} the value to set
|
||
*/
|
||
function setValue (obj, selector, value) {
|
||
traverse(obj, selector, (item, key) => {
|
||
item[key] = value;
|
||
}, true);
|
||
}
|
||
|
||
function removeValue (obj, selector) {
|
||
traverse(obj, selector, (item, key) => {
|
||
if (isArray(item) && /^\d+$/.test(key)) {
|
||
item.splice(parseInt(key), 1);
|
||
} else if (isObject(item)) {
|
||
delete item[key];
|
||
}
|
||
});
|
||
}
|
||
|
||
/**
|
||
* Check whether the given name is an operator. We assume any field name starting with '$' is an operator.
|
||
* This is cheap and safe to do since keys beginning with '$' should be reserved for internal use.
|
||
* @param {String} name
|
||
*/
|
||
function isOperator(name) {
|
||
return !!name && name[0] === '$'
|
||
}
|
||
|
||
/**
|
||
* Simplify expression for easy evaluation with query operators map
|
||
* @param expr
|
||
* @returns {*}
|
||
*/
|
||
function normalize (expr) {
|
||
// normalized primitives
|
||
if (inArray(JS_SIMPLE_TYPES, jsType(expr))) {
|
||
return isRegExp(expr) ? { '$regex': expr } : { '$eq': expr }
|
||
}
|
||
|
||
// normalize object expression
|
||
if (isObjectLike(expr)) {
|
||
let exprKeys = keys(expr);
|
||
|
||
// no valid query operator found, so we do simple comparison
|
||
if (!exprKeys.some(isOperator)) {
|
||
return { '$eq': expr }
|
||
}
|
||
|
||
// ensure valid regex
|
||
if (inArray(exprKeys, '$regex')) {
|
||
let regex = expr['$regex'];
|
||
let options = expr['$options'] || '';
|
||
let modifiers = '';
|
||
if (isString(regex)) {
|
||
modifiers += (regex.ignoreCase || options.indexOf('i') >= 0) ? 'i' : '';
|
||
modifiers += (regex.multiline || options.indexOf('m') >= 0) ? 'm' : '';
|
||
modifiers += (regex.global || options.indexOf('g') >= 0) ? 'g' : '';
|
||
regex = new RegExp(regex, modifiers);
|
||
}
|
||
expr['$regex'] = regex;
|
||
delete expr['$options'];
|
||
}
|
||
}
|
||
|
||
return expr
|
||
}
|
||
|
||
/**
|
||
* Returns a slice of the array
|
||
*
|
||
* @param {Array} xs
|
||
* @param {Number} skip
|
||
* @param {Number} limit
|
||
* @return {Array}
|
||
*/
|
||
function slice (xs, skip, limit = null) {
|
||
// MongoDB $slice works a bit differently from Array.slice
|
||
// Uses single argument for 'limit' and array argument [skip, limit]
|
||
if (isNil(limit)) {
|
||
if (skip < 0) {
|
||
skip = Math.max(0, xs.length + skip);
|
||
limit = xs.length - skip + 1;
|
||
} else {
|
||
limit = skip;
|
||
skip = 0;
|
||
}
|
||
} else {
|
||
if (skip < 0) {
|
||
skip = Math.max(0, xs.length + skip);
|
||
}
|
||
assert(limit > 0, 'Invalid argument value for $slice operator. Limit must be a positive number');
|
||
limit += skip;
|
||
}
|
||
return xs.slice(skip, limit)
|
||
}
|
||
|
||
/**
|
||
* Compute the standard deviation of the data set
|
||
* @param {Array} array of numbers
|
||
* @param {Boolean} if true calculates a sample standard deviation, otherwise calculates a population stddev
|
||
* @return {Number}
|
||
*/
|
||
function stddev (data, sampled) {
|
||
let sum = reduce(data, (acc, n) => acc + n, 0);
|
||
let N = data.length || 1;
|
||
let correction = (sampled && 1) || 0;
|
||
let avg = sum / N;
|
||
return Math.sqrt(reduce(data, (acc, n) => acc + Math.pow(n - avg, 2), 0) / (N - correction))
|
||
}
|
||
|
||
/**
|
||
* Exported to the users to allow writing custom operators
|
||
*/
|
||
function moduleApi () {
|
||
return {
|
||
assert,
|
||
clone,
|
||
cloneDeep,
|
||
each,
|
||
err,
|
||
hashCode,
|
||
getType,
|
||
has,
|
||
includes: inArray.bind(null),
|
||
isArray,
|
||
isBoolean,
|
||
isDate,
|
||
isEmpty,
|
||
isEqual,
|
||
isFunction,
|
||
isNil,
|
||
isNull,
|
||
isNumber,
|
||
isObject,
|
||
isRegExp,
|
||
isString,
|
||
isUndefined,
|
||
keys,
|
||
reduce,
|
||
resolve,
|
||
resolveObj
|
||
}
|
||
}
|
||
|
||
// internal functions available to external operators
|
||
const _internal = () => Object.assign({ computeValue, ops }, moduleApi());
|
||
|
||
// Settings used by Mingo internally
|
||
const settings = {
|
||
key: '_id'
|
||
};
|
||
|
||
/**
|
||
* Setup default settings for Mingo
|
||
* @param options
|
||
*/
|
||
function setup (options) {
|
||
Object.assign(settings, options || {});
|
||
}
|
||
|
||
/**
|
||
* Implementation of system variables
|
||
* @type {Object}
|
||
*/
|
||
const systemVariables = {
|
||
'$$ROOT' (obj, expr, opt) {
|
||
return opt.root
|
||
},
|
||
'$$CURRENT' (obj, expr, opt) {
|
||
return obj
|
||
},
|
||
'$$REMOVE' (obj, expr, opt) {
|
||
return undefined
|
||
}
|
||
};
|
||
|
||
/**
|
||
* Implementation of $redact variables
|
||
*
|
||
* Each function accepts 3 arguments (obj, expr, opt)
|
||
*
|
||
* @type {Object}
|
||
*/
|
||
const redactVariables = {
|
||
'$$KEEP' (obj) {
|
||
return obj
|
||
},
|
||
'$$PRUNE' () {
|
||
return undefined
|
||
},
|
||
'$$DESCEND' (obj, expr, opt) {
|
||
// traverse nested documents iff there is a $cond
|
||
if (!has(expr, '$cond')) return obj
|
||
|
||
let result;
|
||
|
||
each(obj, (current, key) => {
|
||
if (isObjectLike(current)) {
|
||
if (isArray(current)) {
|
||
result = [];
|
||
each(current, (elem) => {
|
||
if (isObject(elem)) {
|
||
elem = redactObj(elem, expr, opt);
|
||
}
|
||
if (!isNil(elem)) result.push(elem);
|
||
});
|
||
} else {
|
||
result = redactObj(current, expr, opt);
|
||
}
|
||
|
||
if (isNil(result)) {
|
||
delete obj[key]; // pruned result
|
||
} else {
|
||
obj[key] = result;
|
||
}
|
||
}
|
||
});
|
||
return obj
|
||
}
|
||
};
|
||
|
||
// system variables
|
||
const SYS_VARS = keys(systemVariables);
|
||
const REDACT_VARS = keys(redactVariables);
|
||
|
||
/**
|
||
* Returns the key used as the collection's objects ids
|
||
*/
|
||
function idKey () {
|
||
return settings.key
|
||
}
|
||
|
||
/**
|
||
* Returns the operators defined for the given operator classes
|
||
*/
|
||
function ops () {
|
||
// Workaround for browser-compatibility bug: on iPhone 6S Safari (and
|
||
// probably some other platforms), `arguments` isn't detected as an array,
|
||
// but has a length field, so functions like `reduce` end up including the
|
||
// length field in their iteration. Copy to a real array.
|
||
let args = Array.prototype.slice.call(arguments);
|
||
return reduce(args, (acc, cls) => into(acc, keys(OPERATORS[cls])), [])
|
||
}
|
||
|
||
/**
|
||
* Returns the result of evaluating a $group operation over a collection
|
||
*
|
||
* @param collection
|
||
* @param field the name of the aggregate operator or field
|
||
* @param expr the expression of the aggregate operator for the field
|
||
* @returns {*}
|
||
*/
|
||
function accumulate (collection, field, expr) {
|
||
if (has(OPERATORS[OP_GROUP], field)) {
|
||
return OPERATORS[OP_GROUP][field](collection, expr)
|
||
}
|
||
|
||
if (isObject(expr)) {
|
||
let result = {};
|
||
each(expr, (val, key) => {
|
||
result[key] = accumulate(collection, key, expr[key]);
|
||
// must run ONLY one group operator per expression
|
||
// if so, return result of the computed value
|
||
if (has(OPERATORS[OP_GROUP], key)) {
|
||
result = result[key];
|
||
// if there are more keys in expression this is bad
|
||
assert(keys(expr).length === 1, "Invalid $group expression '" + JSON.stringify(expr) + "'");
|
||
return false // break
|
||
}
|
||
});
|
||
return result
|
||
}
|
||
}
|
||
|
||
/**
|
||
* Computes the actual value of the expression using the given object as context
|
||
*
|
||
* @param obj the current object from the collection
|
||
* @param expr the expression for the given field
|
||
* @param operator the operator to resolve the field with
|
||
* @param opt {Object} extra options
|
||
* @returns {*}
|
||
*/
|
||
function computeValue (obj, expr, operator = null, opt = {}) {
|
||
opt.root = opt.root || obj;
|
||
|
||
// if the field of the object is a valid operator
|
||
if (has(OPERATORS[OP_EXPRESSION], operator)) {
|
||
return OPERATORS[OP_EXPRESSION][operator](obj, expr, opt)
|
||
}
|
||
|
||
// we also handle $group accumulator operators
|
||
if (has(OPERATORS[OP_GROUP], operator)) {
|
||
// we first fully resolve the expression
|
||
obj = computeValue(obj, expr, null, opt);
|
||
assert(isArray(obj), operator + ' expression must resolve to an array');
|
||
// we pass a null expression because all values have been resolved
|
||
return OPERATORS[OP_GROUP][operator](obj, null, opt)
|
||
}
|
||
|
||
// if expr is a variable for an object field
|
||
// field not used in this case
|
||
if (isString(expr) && expr.length > 0 && expr[0] === '$') {
|
||
// we return system variables as literals
|
||
if (inArray(SYS_VARS, expr)) {
|
||
return systemVariables[expr](obj, null, opt)
|
||
} else if (inArray(REDACT_VARS, expr)) {
|
||
return expr
|
||
}
|
||
|
||
// handle selectors with explicit prefix
|
||
let sysVar = SYS_VARS.filter((v) => expr.indexOf(v + '.') === 0);
|
||
|
||
if (sysVar.length === 1) {
|
||
sysVar = sysVar[0];
|
||
if (sysVar === '$$ROOT') {
|
||
obj = opt.root;
|
||
}
|
||
expr = expr.substr(sysVar.length); // '.' prefix will be sliced off below
|
||
}
|
||
|
||
return resolve(obj, expr.slice(1))
|
||
}
|
||
|
||
// check and return value if already in a resolved state
|
||
switch (jsType(expr)) {
|
||
case T_ARRAY:
|
||
return expr.map(item => computeValue(obj, item))
|
||
case T_OBJECT:
|
||
let result = {};
|
||
each(expr, (val, key) => {
|
||
result[key] = computeValue(obj, val, key, opt);
|
||
// must run ONLY one aggregate operator per expression
|
||
// if so, return result of the computed value
|
||
if ([OP_EXPRESSION, OP_GROUP].some(c => has(OPERATORS[c], key))) {
|
||
// there should be only one operator
|
||
assert(keys(expr).length === 1, "Invalid aggregation expression '" + JSON.stringify(expr) + "'");
|
||
result = result[key];
|
||
return false // break
|
||
}
|
||
});
|
||
return result
|
||
default:
|
||
return expr
|
||
}
|
||
}
|
||
|
||
/**
|
||
* Redact an object
|
||
* @param {Object} obj The object to redact
|
||
* @param {*} expr The redact expression
|
||
* @param {*} opt Options for value
|
||
* @return {*} Returns the redacted value
|
||
*/
|
||
function redactObj (obj, expr, opt = {}) {
|
||
opt.root = opt.root || obj;
|
||
|
||
let result = computeValue(obj, expr, null, opt);
|
||
return inArray(REDACT_VARS, result)
|
||
? redactVariables[result](obj, expr, opt)
|
||
: result
|
||
}
|
||
|
||
/**
|
||
* Returns the absolute value of a number.
|
||
* https://docs.mongodb.com/manual/reference/operator/aggregation/abs/#exp._S_abs
|
||
*
|
||
* @param obj
|
||
* @param expr
|
||
* @return {Number|null|NaN}
|
||
*/
|
||
function $abs (obj, expr) {
|
||
let val = computeValue(obj, expr);
|
||
return (val === null || val === undefined) ? null : Math.abs(val)
|
||
}
|
||
|
||
/**
|
||
* Computes the sum of an array of numbers.
|
||
*
|
||
* @param obj
|
||
* @param expr
|
||
* @returns {Object}
|
||
*/
|
||
function $add (obj, expr) {
|
||
let args = computeValue(obj, expr);
|
||
let foundDate = false;
|
||
let result = reduce(args, (acc, val) => {
|
||
if (isDate(val)) {
|
||
assert(!foundDate, "'$add' can only have one date value");
|
||
foundDate = true;
|
||
val = val.getTime();
|
||
}
|
||
// assume val is a number
|
||
acc += val;
|
||
return acc
|
||
}, 0);
|
||
return foundDate ? new Date(result) : result
|
||
}
|
||
|
||
/**
|
||
* Returns the smallest integer greater than or equal to the specified number.
|
||
*
|
||
* @param obj
|
||
* @param expr
|
||
* @returns {number}
|
||
*/
|
||
function $ceil (obj, expr) {
|
||
let arg = computeValue(obj, expr);
|
||
if (isNil(arg)) return null
|
||
assert(isNumber(arg) || isNaN(arg), '$ceil expression must resolve to a number.');
|
||
return Math.ceil(arg)
|
||
}
|
||
|
||
/**
|
||
* Takes two numbers and divides the first number by the second.
|
||
*
|
||
* @param obj
|
||
* @param expr
|
||
* @returns {number}
|
||
*/
|
||
function $divide (obj, expr) {
|
||
let args = computeValue(obj, expr);
|
||
return args[0] / args[1]
|
||
}
|
||
|
||
/**
|
||
* Raises Euler’s number (i.e. e ) to the specified exponent and returns the result.
|
||
*
|
||
* @param obj
|
||
* @param expr
|
||
* @returns {number}
|
||
*/
|
||
function $exp (obj, expr) {
|
||
let arg = computeValue(obj, expr);
|
||
if (isNil(arg)) return null
|
||
assert(isNumber(arg) || isNaN(arg), '$exp expression must resolve to a number.');
|
||
return Math.exp(arg)
|
||
}
|
||
|
||
/**
|
||
* Returns the largest integer less than or equal to the specified number.
|
||
*
|
||
* @param obj
|
||
* @param expr
|
||
* @returns {number}
|
||
*/
|
||
function $floor (obj, expr) {
|
||
let arg = computeValue(obj, expr);
|
||
if (isNil(arg)) return null
|
||
assert(isNumber(arg) || isNaN(arg), '$floor expression must resolve to a number.');
|
||
return Math.floor(arg)
|
||
}
|
||
|
||
/**
|
||
* Calculates the natural logarithm ln (i.e loge) of a number and returns the result as a double.
|
||
*
|
||
* @param obj
|
||
* @param expr
|
||
* @returns {number}
|
||
*/
|
||
function $ln (obj, expr) {
|
||
let arg = computeValue(obj, expr);
|
||
if (isNil(arg)) return null
|
||
assert(isNumber(arg) || isNaN(arg), '$ln expression must resolve to a number.');
|
||
return Math.log(arg)
|
||
}
|
||
|
||
/**
|
||
* Calculates the log of a number in the specified base and returns the result as a double.
|
||
*
|
||
* @param obj
|
||
* @param expr
|
||
* @returns {number}
|
||
*/
|
||
function $log (obj, expr) {
|
||
let args = computeValue(obj, expr);
|
||
const msg = '$log expression must resolve to array(2) of numbers';
|
||
assert(isArray(args) && args.length === 2, msg);
|
||
if (args.some(isNil)) return null
|
||
assert(args.some(isNaN) || args.every(isNumber), msg);
|
||
return Math.log10(args[0]) / Math.log10(args[1])
|
||
}
|
||
|
||
/**
|
||
* Calculates the log base 10 of a number and returns the result as a double.
|
||
*
|
||
* @param obj
|
||
* @param expr
|
||
* @returns {number}
|
||
*/
|
||
function $log10 (obj, expr) {
|
||
let arg = computeValue(obj, expr);
|
||
if (isNil(arg)) return null
|
||
assert(isNumber(arg) || isNaN(arg), '$log10 expression must resolve to a number.');
|
||
return Math.log10(arg)
|
||
}
|
||
|
||
/**
|
||
* Takes two numbers and calculates the modulo of the first number divided by the second.
|
||
*
|
||
* @param obj
|
||
* @param expr
|
||
* @returns {number}
|
||
*/
|
||
function $mod (obj, expr) {
|
||
let args = computeValue(obj, expr);
|
||
return args[0] % args[1]
|
||
}
|
||
|
||
/**
|
||
* Computes the product of an array of numbers.
|
||
*
|
||
* @param obj
|
||
* @param expr
|
||
* @returns {Object}
|
||
*/
|
||
function $multiply (obj, expr) {
|
||
let args = computeValue(obj, expr);
|
||
return reduce(args, (acc, num) => acc * num, 1)
|
||
}
|
||
|
||
/**
|
||
* Raises a number to the specified exponent and returns the result.
|
||
*
|
||
* @param obj
|
||
* @param expr
|
||
* @returns {Object}
|
||
*/
|
||
function $pow (obj, expr) {
|
||
let args = computeValue(obj, expr);
|
||
|
||
assert(isArray(args) && args.length === 2 && args.every(isNumber), '$pow expression must resolve to array(2) of numbers');
|
||
assert(!(args[0] === 0 && args[1] < 0), '$pow cannot raise 0 to a negative exponent');
|
||
|
||
return Math.pow(args[0], args[1])
|
||
}
|
||
|
||
/**
|
||
* Rounds a number to to a whole integer or to a specified decimal place.
|
||
* @param {*} obj
|
||
* @param {*} expr
|
||
*/
|
||
function $round (obj, expr) {
|
||
let args = computeValue(obj, expr);
|
||
let num = args[0];
|
||
let place = args[1];
|
||
if (isNil(num) || isNaN(num) || Math.abs(num) === Infinity) return num
|
||
assert(isNumber(num), '$round expression must resolve to a number.');
|
||
return truncate(num, place, true)
|
||
}
|
||
|
||
/**
|
||
* Calculates the square root of a positive number and returns the result as a double.
|
||
*
|
||
* @param obj
|
||
* @param expr
|
||
* @returns {number}
|
||
*/
|
||
function $sqrt (obj, expr) {
|
||
let n = computeValue(obj, expr);
|
||
if (isNil(n)) return null
|
||
assert(isNumber(n) && n > 0 || isNaN(n), '$sqrt expression must resolve to non-negative number.');
|
||
return Math.sqrt(n)
|
||
}
|
||
|
||
/**
|
||
* Takes an array that contains two numbers or two dates and subtracts the second value from the first.
|
||
*
|
||
* @param obj
|
||
* @param expr
|
||
* @returns {number}
|
||
*/
|
||
function $subtract (obj, expr) {
|
||
let args = computeValue(obj, expr);
|
||
return args[0] - args[1]
|
||
}
|
||
|
||
/**
|
||
* Truncates a number to a whole integer or to a specified decimal place.
|
||
*
|
||
* @param obj
|
||
* @param expr
|
||
* @returns {number}
|
||
*/
|
||
function $trunc (obj, expr) {
|
||
let arr = computeValue(obj, expr);
|
||
let num = arr[0];
|
||
let places = arr[1];
|
||
if (isNil(num) || isNaN(num) || Math.abs(num) === Infinity) return num
|
||
assert(isNumber(num), '$trunc expression must resolve to a number.');
|
||
assert(isNil(places) || (isNumber(places) && places > -20 && places < 100), "$trunc expression has invalid place");
|
||
return truncate(num, places, false)
|
||
}
|
||
|
||
/**
|
||
* Truncates integer value to number of places. If roundOff is specified round value instead to the number of places
|
||
* @param {Number} num
|
||
* @param {Number} places
|
||
* @param {Boolean} roundOff
|
||
*/
|
||
function truncate(num, places, roundOff) {
|
||
places = places || 0;
|
||
let sign = Math.abs(num) === num ? 1 : -1;
|
||
num = Math.abs(num);
|
||
|
||
let result = Math.trunc(num);
|
||
let decimals = num - result;
|
||
|
||
if (places === 0) {
|
||
let firstDigit = Math.trunc(10 * decimals);
|
||
if (roundOff && (result & 1) === 1 && firstDigit >= 5) {
|
||
result++;
|
||
}
|
||
} else if (places > 0) {
|
||
let offset = Math.pow(10, places);
|
||
let remainder = Math.trunc(decimals * offset);
|
||
|
||
// last digit before cut off
|
||
let lastDigit = Math.trunc(decimals * offset * 10) % 10;
|
||
|
||
// add one if last digit is greater than 5
|
||
if (roundOff && lastDigit > 5) {
|
||
remainder += 1;
|
||
}
|
||
|
||
// compute decimal remainder and add to whole number
|
||
result += (remainder / offset);
|
||
} else if (places < 0) {
|
||
// handle negative decimal places
|
||
let offset = Math.pow(10, -1*places);
|
||
let excess = result % offset;
|
||
result = Math.max(0, result - excess);
|
||
|
||
// for negative values the absolute must increase so we round up the last digit if >= 5
|
||
if (roundOff && sign === -1) {
|
||
while (excess > 10) {
|
||
excess -= excess % 10;
|
||
}
|
||
if (result > 0 && excess >= 5) {
|
||
result += offset;
|
||
}
|
||
}
|
||
}
|
||
|
||
return result * sign
|
||
}
|
||
|
||
/**
|
||
* Returns the element at the specified array index.
|
||
*
|
||
* @param {Object} obj
|
||
* @param {*} expr
|
||
* @return {*}
|
||
*/
|
||
function $arrayElemAt (obj, expr) {
|
||
let arr = computeValue(obj, expr);
|
||
assert(isArray(arr) && arr.length === 2, '$arrayElemAt expression must resolve to array(2)');
|
||
assert(isArray(arr[0]), 'First operand to $arrayElemAt must resolve to an array');
|
||
assert(isNumber(arr[1]), 'Second operand to $arrayElemAt must resolve to an integer');
|
||
let idx = arr[1];
|
||
arr = arr[0];
|
||
if (idx < 0 && Math.abs(idx) <= arr.length) {
|
||
return arr[idx + arr.length]
|
||
} else if (idx >= 0 && idx < arr.length) {
|
||
return arr[idx]
|
||
}
|
||
return undefined
|
||
}
|
||
|
||
/**
|
||
* Converts an array of key value pairs to a document.
|
||
*/
|
||
function $arrayToObject (obj, expr) {
|
||
let arr = computeValue(obj, expr);
|
||
assert(isArray(arr), '$arrayToObject expression must resolve to an array');
|
||
return reduce(arr, (newObj, val) => {
|
||
if (isArray(val) && val.length == 2) {
|
||
newObj[val[0]] = val[1];
|
||
} else {
|
||
assert(isObject(val) && has(val, 'k') && has(val, 'v'), '$arrayToObject expression is invalid.');
|
||
newObj[val.k] = val.v;
|
||
}
|
||
return newObj
|
||
}, {})
|
||
}
|
||
|
||
/**
|
||
* Concatenates arrays to return the concatenated array.
|
||
*
|
||
* @param {Object} obj
|
||
* @param {*} expr
|
||
* @return {*}
|
||
*/
|
||
function $concatArrays (obj, expr) {
|
||
let arr = computeValue(obj, expr, null);
|
||
assert(isArray(arr), '$concatArrays must resolve to an array');
|
||
if (arr.some(isNil)) return null
|
||
return arr.reduce((acc, item) => into(acc, item), [])
|
||
}
|
||
|
||
/**
|
||
* Selects a subset of the array to return an array with only the elements that match the filter condition.
|
||
*
|
||
* @param {Object} obj [description]
|
||
* @param {*} expr [description]
|
||
* @return {*} [description]
|
||
*/
|
||
function $filter (obj, expr) {
|
||
let input = computeValue(obj, expr.input);
|
||
let asVar = expr['as'];
|
||
let condExpr = expr['cond'];
|
||
|
||
assert(isArray(input), "$filter 'input' expression must resolve to an array");
|
||
|
||
return input.filter((o) => {
|
||
// inject variable
|
||
let tempObj = {};
|
||
tempObj['$' + asVar] = o;
|
||
return computeValue(tempObj, condExpr) === true
|
||
})
|
||
}
|
||
|
||
/**
|
||
* Returns a boolean indicating whether a specified value is in an array.
|
||
*
|
||
* @param {Object} obj
|
||
* @param {Array} expr
|
||
*/
|
||
function $in (obj, expr) {
|
||
let val = computeValue(obj, expr[0]);
|
||
let arr = computeValue(obj, expr[1]);
|
||
assert(isArray(arr), '$in second argument must be an array');
|
||
return arr.some(isEqual.bind(null, val))
|
||
}
|
||
|
||
/**
|
||
* Searches an array for an occurrence of a specified value and returns the array index of the first occurrence.
|
||
* If the substring is not found, returns -1.
|
||
*
|
||
* @param {Object} obj
|
||
* @param {*} expr
|
||
* @return {*}
|
||
*/
|
||
function $indexOfArray (obj, expr) {
|
||
let args = computeValue(obj, expr);
|
||
if (isNil(args)) return null
|
||
|
||
let arr = args[0];
|
||
let searchValue = args[1];
|
||
if (isNil(arr)) return null
|
||
|
||
assert(isArray(arr), '$indexOfArray expression must resolve to an array.');
|
||
|
||
let start = args[2] || 0;
|
||
let end = args[3];
|
||
if (isNil(end)) end = arr.length;
|
||
if (start > end) return -1
|
||
|
||
assert(start >= 0 && end >= 0, '$indexOfArray expression is invalid');
|
||
|
||
if (start > 0 || end < arr.length) {
|
||
arr = arr.slice(start, end);
|
||
}
|
||
return arr.findIndex(isEqual.bind(null, searchValue)) + start
|
||
}
|
||
|
||
/**
|
||
* Determines if the operand is an array. Returns a boolean.
|
||
*
|
||
* @param {Object} obj
|
||
* @param {*} expr
|
||
* @return {Boolean}
|
||
*/
|
||
function $isArray (obj, expr) {
|
||
return isArray(computeValue(obj, expr[0]))
|
||
}
|
||
|
||
/**
|
||
* Applies a sub-expression to each element of an array and returns the array of resulting values in order.
|
||
*
|
||
* @param obj
|
||
* @param expr
|
||
* @returns {Array|*}
|
||
*/
|
||
function $map (obj, expr) {
|
||
let inputExpr = computeValue(obj, expr.input);
|
||
assert(isArray(inputExpr), `$map 'input' expression must resolve to an array`);
|
||
|
||
let asExpr = expr['as'];
|
||
let inExpr = expr['in'];
|
||
|
||
// HACK: add the "as" expression as a value on the object to take advantage of "resolve()"
|
||
// which will reduce to that value when invoked. The reference to the as expression will be prefixed with "$$".
|
||
// But since a "$" is stripped of before passing the name to "resolve()" we just need to prepend "$" to the key.
|
||
let tempKey = '$' + asExpr;
|
||
return inputExpr.map(item => {
|
||
obj[tempKey] = item;
|
||
return computeValue(obj, inExpr)
|
||
})
|
||
}
|
||
|
||
/**
|
||
* Converts a document to an array of documents representing key-value pairs.
|
||
*/
|
||
function $objectToArray (obj, expr) {
|
||
let val = computeValue(obj, expr);
|
||
assert(isObject(val), '$objectToArray expression must resolve to an object');
|
||
let arr = [];
|
||
each(val, (v,k) => arr.push({k,v}));
|
||
return arr
|
||
}
|
||
|
||
/**
|
||
* Returns an array whose elements are a generated sequence of numbers.
|
||
*
|
||
* @param {Object} obj
|
||
* @param {*} expr
|
||
* @return {*}
|
||
*/
|
||
function $range (obj, expr) {
|
||
let arr = computeValue(obj, expr);
|
||
let start = arr[0];
|
||
let end = arr[1];
|
||
let step = arr[2] || 1;
|
||
|
||
let result = [];
|
||
|
||
while ((start < end && step > 0) || (start > end && step < 0)) {
|
||
result.push(start);
|
||
start += step;
|
||
}
|
||
|
||
return result
|
||
}
|
||
|
||
/**
|
||
* Applies an expression to each element in an array and combines them into a single value.
|
||
*
|
||
* @param {Object} obj
|
||
* @param {*} expr
|
||
*/
|
||
function $reduce (obj, expr) {
|
||
let input = computeValue(obj, expr.input);
|
||
let initialValue = computeValue(obj, expr.initialValue);
|
||
let inExpr = expr['in'];
|
||
|
||
if (isNil(input)) return null
|
||
assert(isArray(input), "$reduce 'input' expression must resolve to an array");
|
||
return reduce(input, (acc, n) => computeValue({ '$value': acc, '$this': n }, inExpr), initialValue)
|
||
}
|
||
|
||
/**
|
||
* Returns an array with the elements in reverse order.
|
||
*
|
||
* @param {Object} obj
|
||
* @param {*} expr
|
||
* @return {*}
|
||
*/
|
||
function $reverseArray (obj, expr) {
|
||
let arr = computeValue(obj, expr);
|
||
|
||
if (isNil(arr)) return null
|
||
assert(isArray(arr), '$reverseArray expression must resolve to an array');
|
||
|
||
let result = [];
|
||
into(result, arr);
|
||
result.reverse();
|
||
return result
|
||
}
|
||
|
||
/**
|
||
* Counts and returns the total the number of items in an array.
|
||
*
|
||
* @param obj
|
||
* @param expr
|
||
*/
|
||
function $size (obj, expr) {
|
||
let value = computeValue(obj, expr);
|
||
return isArray(value) ? value.length : undefined
|
||
}
|
||
|
||
/**
|
||
* Returns a subset of an array.
|
||
*
|
||
* @param {Object} obj
|
||
* @param {*} expr
|
||
* @return {*}
|
||
*/
|
||
function $slice (obj, expr) {
|
||
let arr = computeValue(obj, expr);
|
||
return slice(arr[0], arr[1], arr[2])
|
||
}
|
||
|
||
/**
|
||
* Merge two lists together.
|
||
*
|
||
* Transposes an array of input arrays so that the first element of the output array would be an array containing,
|
||
* the first element of the first input array, the first element of the second input array, etc.
|
||
*
|
||
* @param {Obj} obj
|
||
* @param {*} expr
|
||
* @return {*}
|
||
*/
|
||
function $zip (obj, expr) {
|
||
let inputs = computeValue(obj, expr.inputs);
|
||
let useLongestLength = expr.useLongestLength || false;
|
||
|
||
assert(isArray(inputs), "'inputs' expression must resolve to an array");
|
||
assert(isBoolean(useLongestLength), "'useLongestLength' must be a boolean");
|
||
|
||
if (isArray(expr.defaults)) {
|
||
assert(truthy(useLongestLength), "'useLongestLength' must be set to true to use 'defaults'");
|
||
}
|
||
|
||
let zipCount = 0;
|
||
|
||
for (let i = 0, len = inputs.length; i < len; i++) {
|
||
let arr = inputs[i];
|
||
|
||
if (isNil(arr)) return null
|
||
|
||
assert(isArray(arr), "'inputs' expression values must resolve to an array or null");
|
||
|
||
zipCount = useLongestLength
|
||
? Math.max(zipCount, arr.length)
|
||
: Math.min(zipCount || arr.length, arr.length);
|
||
}
|
||
|
||
let result = [];
|
||
let defaults = expr.defaults || [];
|
||
|
||
for (let i = 0; i < zipCount; i++) {
|
||
let temp = inputs.map((val, index) => {
|
||
return isNil(val[i]) ? (defaults[index] || null) : val[i]
|
||
});
|
||
result.push(temp);
|
||
}
|
||
|
||
return result
|
||
}
|
||
|
||
/**
|
||
* Combines multiple documents into a single document.
|
||
* @param {*} obj
|
||
* @param {*} expr
|
||
*/
|
||
function $mergeObjects (obj, expr) {
|
||
let docs = computeValue(obj, expr);
|
||
if (isArray(docs)) {
|
||
return reduce(docs, (memo, o) => Object.assign(memo, o), {})
|
||
}
|
||
return {}
|
||
}
|
||
|
||
/**
|
||
* Returns true only when all its expressions evaluate to true. Accepts any number of argument expressions.
|
||
*
|
||
* @param obj
|
||
* @param expr
|
||
* @returns {boolean}
|
||
*/
|
||
function $and (obj, expr) {
|
||
let value = computeValue(obj, expr);
|
||
return truthy(value) && value.every(truthy)
|
||
}
|
||
|
||
/**
|
||
* Returns true when any of its expressions evaluates to true. Accepts any number of argument expressions.
|
||
*
|
||
* @param obj
|
||
* @param expr
|
||
* @returns {boolean}
|
||
*/
|
||
function $or (obj, expr) {
|
||
let value = computeValue(obj, expr);
|
||
return truthy(value) && value.some(truthy)
|
||
}
|
||
|
||
/**
|
||
* Returns the boolean value that is the opposite of its argument expression. Accepts a single argument expression.
|
||
*
|
||
* @param obj
|
||
* @param expr
|
||
* @returns {boolean}
|
||
*/
|
||
function $not (obj, expr) {
|
||
return !computeValue(obj, expr[0])
|
||
}
|
||
|
||
/**
|
||
* Returns an iterator
|
||
* @param {*} source An iterable source (Array, Function, Object{next:Function})
|
||
*/
|
||
function Lazy (source) {
|
||
return (source instanceof Iterator) ? source : new Iterator(source)
|
||
}
|
||
|
||
Lazy.isIterator = isIterator;
|
||
|
||
/**
|
||
* Checks whether the given object is compatible with iterator i.e Object{next:Function}
|
||
* @param {*} o An object
|
||
*/
|
||
function isIterator (o) {
|
||
return !!o && typeof o === 'object' && isFn(o.next)
|
||
}
|
||
|
||
function isFn (f) {
|
||
return !!f && typeof f === 'function'
|
||
}
|
||
|
||
function dropItem (array, i) {
|
||
let rest = array.slice(i + 1);
|
||
array.splice(i);
|
||
Array.prototype.push.apply(array, rest);
|
||
}
|
||
|
||
// stop iteration error
|
||
const DONE = new Error();
|
||
|
||
// Lazy function type flags
|
||
const LAZY_MAP = 1;
|
||
const LAZY_FILTER = 2;
|
||
const LAZY_TAKE = 3;
|
||
const LAZY_DROP = 4;
|
||
|
||
function baseIterator (nextFn, iteratees, buffer) {
|
||
|
||
let done = false;
|
||
let index = -1;
|
||
let bIndex = 0; // index for the buffer
|
||
|
||
return function (b) {
|
||
|
||
// special hack to collect all values into buffer
|
||
b = b === buffer;
|
||
|
||
try {
|
||
|
||
outer: while (!done) {
|
||
let o = nextFn();
|
||
index++;
|
||
|
||
let mIndex = -1;
|
||
let mSize = iteratees.length;
|
||
let innerDone = false;
|
||
|
||
while (++mIndex < mSize) {
|
||
let member = iteratees[mIndex],
|
||
func = member.func,
|
||
type = member.type;
|
||
|
||
switch (type) {
|
||
case LAZY_MAP:
|
||
o = func(o, index);
|
||
break
|
||
case LAZY_FILTER:
|
||
if (!func(o, index)) continue outer
|
||
break
|
||
case LAZY_TAKE:
|
||
--member.func;
|
||
if (!member.func) innerDone = true;
|
||
break
|
||
case LAZY_DROP:
|
||
--member.func;
|
||
if (!member.func) dropItem(iteratees, mIndex);
|
||
continue outer
|
||
default:
|
||
break outer
|
||
}
|
||
}
|
||
|
||
done = innerDone;
|
||
|
||
if (b) {
|
||
buffer[bIndex++] = o;
|
||
} else {
|
||
return { value: o, done: false }
|
||
}
|
||
}
|
||
} catch (e) {
|
||
if (e !== DONE) throw e
|
||
}
|
||
done = true;
|
||
return { done: true }
|
||
}
|
||
}
|
||
|
||
class Iterator {
|
||
/**
|
||
* @param {*} source An iterable object or function.
|
||
* Array - return one element per cycle
|
||
* Object{next:Function} - call next() for the next value (this also handles generator functions)
|
||
* Function - call to return the next value
|
||
* @param {Function} fn An optional transformation function
|
||
*/
|
||
constructor (source) {
|
||
this.__iteratees = []; // lazy function chain
|
||
this.__first = false; // flag whether to return a single value
|
||
this.__done = false;
|
||
this.__buf = [];
|
||
|
||
if (isFn(source)) {
|
||
// make iterable
|
||
source = { next: source };
|
||
}
|
||
|
||
if (isIterator(source)) {
|
||
const src = source;
|
||
source = () => {
|
||
let o = src.next();
|
||
if (o.done) throw DONE
|
||
return o.value
|
||
};
|
||
} else if (Array.isArray(source)) {
|
||
const data = source;
|
||
const size = data.length;
|
||
let index = 0;
|
||
source = () => {
|
||
if (index < size) return data[index++]
|
||
throw DONE
|
||
};
|
||
} else if (!isFn(source)) {
|
||
throw new Error("Source is not iterable. Must be Array, Function or Object{next:Function}")
|
||
}
|
||
|
||
// create next function
|
||
this.next = baseIterator(source, this.__iteratees, this.__buf);
|
||
}
|
||
|
||
_validate () {
|
||
if (this.__first) throw new Error("Cannot add iteratee/transform after `first()`")
|
||
}
|
||
|
||
/**
|
||
* Add an iteratee to this lazy sequence
|
||
* @param {Object} iteratee
|
||
*/
|
||
_push (iteratee) {
|
||
this._validate();
|
||
this.__iteratees.push(iteratee);
|
||
return this
|
||
}
|
||
|
||
// Iteratees methods
|
||
|
||
/**
|
||
* Transform each item in the sequence to a new value
|
||
* @param {Function} f
|
||
*/
|
||
map (f) {
|
||
return this._push({ type: LAZY_MAP, func: f })
|
||
}
|
||
|
||
/**
|
||
* Select only items matching the given predicate
|
||
* @param {Function} pred
|
||
*/
|
||
filter (pred) {
|
||
return this._push({ type: LAZY_FILTER, func: pred })
|
||
}
|
||
|
||
/**
|
||
* Take given numbe for values from sequence
|
||
* @param {Number} n A number greater than 0
|
||
*/
|
||
take (n) {
|
||
return n > 0 ? this._push({ type: LAZY_TAKE, func: n }) : this
|
||
}
|
||
|
||
/**
|
||
* Drop a number of values from the sequence
|
||
* @param {Number} n Number of items to drop greater than 0
|
||
*/
|
||
drop (n) {
|
||
return n > 0 ? this._push({ type: LAZY_DROP, func: n }) : this
|
||
}
|
||
|
||
// Transformations
|
||
|
||
/**
|
||
* Returns a new lazy object with results of the transformation
|
||
* The entire sequence is realized.
|
||
*
|
||
* @param {Function} fn Tranform function of type (Array) => (Any)
|
||
*/
|
||
transform (fn) {
|
||
this._validate();
|
||
let self = this;
|
||
let iter;
|
||
return Lazy(() => {
|
||
if (!iter) {
|
||
iter = Lazy(fn(self.value()));
|
||
}
|
||
return iter.next()
|
||
})
|
||
}
|
||
|
||
/**
|
||
* Mark this lazy object to return only the first result on `lazy.value()`.
|
||
* No more iteratees or transformations can be added after this method is called.
|
||
*/
|
||
first () {
|
||
this.take(1);
|
||
this.__first = true;
|
||
return this
|
||
}
|
||
|
||
// Terminal methods
|
||
|
||
/**
|
||
* Returns the fully realized values of the iterators.
|
||
* The return value will be an array unless `lazy.first()` was used.
|
||
* The realized values are cached for subsequent calls
|
||
*/
|
||
value () {
|
||
if (!this.__done) {
|
||
this.__done = this.next(this.__buf).done;
|
||
}
|
||
return this.__first ? this.__buf[0] : this.__buf
|
||
}
|
||
|
||
/**
|
||
* Execute the funcion for each value. Will stop when an execution returns false.
|
||
* @param {Function} f
|
||
* @returns {Boolean} false iff `f` return false for any execution, otherwise true
|
||
*/
|
||
each (f) {
|
||
while (1) {
|
||
let o = this.next();
|
||
if (o.done) break
|
||
if (f(o.value) === false) return false
|
||
}
|
||
return true
|
||
}
|
||
|
||
/**
|
||
* Returns the reduction of sequence according the reducing function
|
||
*
|
||
* @param {*} f a reducing function
|
||
* @param {*} init
|
||
*/
|
||
reduce (f, init) {
|
||
|
||
let o = this.next();
|
||
let i = 0;
|
||
|
||
if (init === undefined && !o.done) {
|
||
init = o.value;
|
||
o = this.next();
|
||
i++;
|
||
}
|
||
|
||
while (!o.done) {
|
||
init = f(init, o.value, i++);
|
||
o = this.next();
|
||
}
|
||
|
||
return init
|
||
}
|
||
|
||
/**
|
||
* Returns the number of matched items in the sequence
|
||
*/
|
||
size () {
|
||
return this.reduce((acc,n) => ++acc, 0)
|
||
}
|
||
}
|
||
|
||
if (typeof Symbol === 'function') {
|
||
Iterator.prototype[Symbol.iterator] = function() {
|
||
return this
|
||
};
|
||
}
|
||
|
||
/**
|
||
* Aggregator for defining filter using mongoDB aggregation pipeline syntax
|
||
*
|
||
* @param operators an Array of pipeline operators
|
||
* @constructor
|
||
*/
|
||
class Aggregator {
|
||
|
||
constructor (operators, options) {
|
||
this.__operators = operators;
|
||
this.__options = options;
|
||
}
|
||
|
||
/**
|
||
* Returns an `Lazy` iterator for processing results of pipeline
|
||
*
|
||
* @param {*} collection An array or iterator object
|
||
* @param {Query} query the `Query` object to use as context
|
||
* @returns {Iterator} an iterator object
|
||
*/
|
||
stream (collection, query) {
|
||
collection = Lazy(collection);
|
||
|
||
const pipelineOperators = OPERATORS[OP_PIPELINE];
|
||
|
||
if (!isEmpty(this.__operators)) {
|
||
// run aggregation pipeline
|
||
each(this.__operators, (operator) => {
|
||
let key = keys(operator);
|
||
assert(key.length === 1 && inArray(ops(OP_PIPELINE), key[0]), `invalid aggregation operator ${key}`);
|
||
key = key[0];
|
||
if (query && query instanceof Query) {
|
||
collection = pipelineOperators[key].call(query, collection, operator[key], this.__options);
|
||
} else {
|
||
collection = pipelineOperators[key](collection, operator[key], this.__options);
|
||
}
|
||
});
|
||
}
|
||
return collection
|
||
}
|
||
|
||
/**
|
||
* Return the results of the aggregation as an array.
|
||
* @param {*} collection
|
||
* @param {*} query
|
||
*/
|
||
run (collection, query) {
|
||
return this.stream(collection, query).value()
|
||
}
|
||
}
|
||
|
||
/**
|
||
* Return the result collection after running the aggregation pipeline for the given collection.
|
||
* Shorthand for `(new Aggregator(pipeline, options)).run(collection)`
|
||
*
|
||
* @param {Array} collection Collection or stream of objects
|
||
* @param {Array} pipeline The pipeline operators to use
|
||
* @returns {Array}
|
||
*/
|
||
function aggregate (collection, pipeline, options) {
|
||
assert(isArray(pipeline), 'Aggregation pipeline must be an array');
|
||
return (new Aggregator(pipeline, options)).run(collection)
|
||
}
|
||
|
||
/**
|
||
* Cursor to iterate and perform filtering on matched objects
|
||
* @param collection
|
||
* @param query
|
||
* @param projection
|
||
* @constructor
|
||
*/
|
||
class Cursor {
|
||
|
||
constructor (source, query, projection) {
|
||
this.__filterFn = query.test.bind(query);
|
||
this.__query = query;
|
||
this.__source = source;
|
||
this.__projection = projection || query.__projection;
|
||
this.__operators = [];
|
||
this.__result = null;
|
||
this.__stack = [];
|
||
this.__options = {};
|
||
}
|
||
|
||
_fetch () {
|
||
|
||
if (!!this.__result) return this.__result
|
||
|
||
// add projection operator
|
||
if (isObject(this.__projection)) this.__operators.push({ '$project': this.__projection });
|
||
|
||
// filter collection
|
||
this.__result = Lazy(this.__source).filter(this.__filterFn);
|
||
|
||
if (this.__operators.length > 0) {
|
||
this.__result = (new Aggregator(this.__operators, this.__options)).stream(this.__result, this.__query);
|
||
}
|
||
|
||
return this.__result
|
||
}
|
||
|
||
/**
|
||
* Return remaining objects in the cursor as an array. This method exhausts the cursor
|
||
* @returns {Array}
|
||
*/
|
||
all () {
|
||
return this._fetch().value()
|
||
}
|
||
|
||
/**
|
||
* Returns the number of objects return in the cursor. This method exhausts the cursor
|
||
* @returns {Number}
|
||
*/
|
||
count () {
|
||
return this.all().length
|
||
}
|
||
|
||
/**
|
||
* Returns a cursor that begins returning results only after passing or skipping a number of documents.
|
||
* @param {Number} n the number of results to skip.
|
||
* @return {Cursor} Returns the cursor, so you can chain this call.
|
||
*/
|
||
skip (n) {
|
||
this.__operators.push({ '$skip': n });
|
||
return this
|
||
}
|
||
|
||
/**
|
||
* Constrains the size of a cursor's result set.
|
||
* @param {Number} n the number of results to limit to.
|
||
* @return {Cursor} Returns the cursor, so you can chain this call.
|
||
*/
|
||
limit (n) {
|
||
this.__operators.push({ '$limit': n });
|
||
return this
|
||
}
|
||
|
||
/**
|
||
* Returns results ordered according to a sort specification.
|
||
* @param {Object} modifier an object of key and values specifying the sort order. 1 for ascending and -1 for descending
|
||
* @return {Cursor} Returns the cursor, so you can chain this call.
|
||
*/
|
||
sort (modifier) {
|
||
this.__operators.push({ '$sort': modifier });
|
||
return this
|
||
}
|
||
|
||
/**
|
||
* Specifies the collation for the cursor returned by the `mingo.Query.find`
|
||
* @param {*} options
|
||
*/
|
||
collation (options) {
|
||
this.__options['collation'] = options;
|
||
return this
|
||
}
|
||
|
||
/**
|
||
* Returns the next document in a cursor.
|
||
* @returns {Object | Boolean}
|
||
*/
|
||
next () {
|
||
if (!this.__stack) return // done
|
||
if (this.__stack.length > 0) return this.__stack.pop() // yield value obtains in hasNext()
|
||
let o = this._fetch().next();
|
||
|
||
if (!o.done) return o.value
|
||
this.__stack = null;
|
||
return
|
||
}
|
||
|
||
/**
|
||
* Returns true if the cursor has documents and can be iterated.
|
||
* @returns {boolean}
|
||
*/
|
||
hasNext () {
|
||
if (!this.__stack) return false // done
|
||
if (this.__stack.length > 0) return true // there is a value on stack
|
||
|
||
let o = this._fetch().next();
|
||
if (!o.done) {
|
||
this.__stack.push(o.value);
|
||
} else {
|
||
this.__stack = null;
|
||
}
|
||
|
||
return !!this.__stack
|
||
}
|
||
|
||
/**
|
||
* Applies a function to each document in a cursor and collects the return values in an array.
|
||
* @param callback
|
||
* @returns {Array}
|
||
*/
|
||
map (callback) {
|
||
return this._fetch().map(callback).value()
|
||
}
|
||
|
||
/**
|
||
* Applies a JavaScript function for every document in a cursor.
|
||
* @param callback
|
||
*/
|
||
forEach (callback) {
|
||
this._fetch().each(callback);
|
||
}
|
||
}
|
||
|
||
if (typeof Symbol === 'function') {
|
||
/**
|
||
* Applies an [ES2015 Iteration protocol][] compatible implementation
|
||
* [ES2015 Iteration protocol]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Iteration_protocols
|
||
* @returns {Object}
|
||
*/
|
||
Cursor.prototype[Symbol.iterator] = function () {
|
||
return this._fetch()
|
||
};
|
||
}
|
||
|
||
/**
|
||
* Query object to test collection elements with
|
||
* @param criteria the pass criteria for the query
|
||
* @param projection optional projection specifiers
|
||
* @constructor
|
||
*/
|
||
class Query {
|
||
|
||
constructor (criteria, projection) {
|
||
this.__criteria = criteria;
|
||
this.__projection = projection || {};
|
||
this.__compiled = [];
|
||
this._compile();
|
||
}
|
||
|
||
_compile () {
|
||
assert(isObject(this.__criteria), 'query criteria must be an object');
|
||
|
||
let whereOperator;
|
||
|
||
each(this.__criteria, (expr, field) => {
|
||
// save $where operators to be executed after other operators
|
||
if ('$where' === field) {
|
||
whereOperator = { field: field, expr: expr };
|
||
} else if ('$expr' === field) {
|
||
this._processOperator(field, field, expr);
|
||
} else if (inArray(['$and', '$or', '$nor'], field)) {
|
||
this._processOperator(field, field, expr);
|
||
} else {
|
||
// normalize expression
|
||
assert(!isOperator(field), `unknown top level operator: ${field}`);
|
||
expr = normalize(expr);
|
||
each(expr, (val, op) => {
|
||
this._processOperator(field, op, val);
|
||
});
|
||
}
|
||
|
||
if (isObject(whereOperator)) {
|
||
this._processOperator(whereOperator.field, whereOperator.field, whereOperator.expr);
|
||
}
|
||
});
|
||
}
|
||
|
||
_processOperator (field, operator, value) {
|
||
assert(has(OPERATORS[OP_QUERY], operator), `invalid query operator ${operator} detected`);
|
||
this.__compiled.push(OPERATORS[OP_QUERY][operator](field, value));
|
||
}
|
||
|
||
/**
|
||
* Checks if the object passes the query criteria. Returns true if so, false otherwise.
|
||
* @param obj
|
||
* @returns {boolean}
|
||
*/
|
||
test (obj) {
|
||
for (let i = 0, len = this.__compiled.length; i < len; i++) {
|
||
if (!this.__compiled[i](obj)) {
|
||
return false
|
||
}
|
||
}
|
||
return true
|
||
}
|
||
|
||
/**
|
||
* Performs a query on a collection and returns a cursor object.
|
||
* @param collection
|
||
* @param projection
|
||
* @returns {Cursor}
|
||
*/
|
||
find (collection, projection) {
|
||
return new Cursor(collection, this, projection)
|
||
}
|
||
|
||
/**
|
||
* Remove matched documents from the collection returning the remainder
|
||
* @param collection
|
||
* @returns {Array}
|
||
*/
|
||
remove (collection) {
|
||
return reduce(collection, (acc, obj) => {
|
||
if (!this.test(obj)) acc.push(obj);
|
||
return acc
|
||
}, [])
|
||
}
|
||
}
|
||
|
||
/**
|
||
* Performs a query on a collection and returns a cursor object.
|
||
*
|
||
* @param collection
|
||
* @param criteria
|
||
* @param projection
|
||
* @returns {Cursor}
|
||
*/
|
||
function find (collection, criteria, projection) {
|
||
return new Query(criteria).find(collection, projection)
|
||
}
|
||
|
||
/**
|
||
* Returns a new array without objects which match the criteria
|
||
*
|
||
* @param collection
|
||
* @param criteria
|
||
* @returns {Array}
|
||
*/
|
||
function remove (collection, criteria) {
|
||
return new Query(criteria).remove(collection)
|
||
}
|
||
|
||
/**
|
||
* Query and Projection Operators. https://docs.mongodb.com/manual/reference/operator/query/
|
||
*/
|
||
|
||
/**
|
||
* Checks that two values are equal.
|
||
*
|
||
* @param a The lhs operand as resolved from the object by the given selector
|
||
* @param b The rhs operand provided by the user
|
||
* @returns {*}
|
||
*/
|
||
function $eq (a, b) {
|
||
// start with simple equality check
|
||
if (isEqual(a, b)) return true
|
||
|
||
// https://docs.mongodb.com/manual/tutorial/query-for-null-fields/
|
||
if (isNil(a) && isNil(b)) return true
|
||
|
||
// check
|
||
if (isArray(a)) {
|
||
let eq = isEqual.bind(null, b);
|
||
return a.some(eq) || flatten(a, 1).some(eq)
|
||
}
|
||
|
||
return false
|
||
}
|
||
|
||
/**
|
||
* Matches all values that are not equal to the value specified in the query.
|
||
*
|
||
* @param a
|
||
* @param b
|
||
* @returns {boolean}
|
||
*/
|
||
function $ne (a, b) {
|
||
return !$eq(a, b)
|
||
}
|
||
|
||
/**
|
||
* Matches any of the values that exist in an array specified in the query.
|
||
*
|
||
* @param a
|
||
* @param b
|
||
* @returns {*}
|
||
*/
|
||
function $in$1 (a, b) {
|
||
// queries for null should be able to find undefined fields
|
||
if (isNil(a)) return b.some(isNull)
|
||
|
||
return intersection(ensureArray(a), b).length > 0
|
||
}
|
||
|
||
/**
|
||
* Matches values that do not exist in an array specified to the query.
|
||
*
|
||
* @param a
|
||
* @param b
|
||
* @returns {*|boolean}
|
||
*/
|
||
function $nin (a, b) {
|
||
return !$in$1(a, b)
|
||
}
|
||
|
||
/**
|
||
* Matches values that are less than the value specified in the query.
|
||
*
|
||
* @param a
|
||
* @param b
|
||
* @returns {boolean}
|
||
*/
|
||
function $lt (a, b) {
|
||
return compare$1(a, b, (x,y) => x < y)
|
||
}
|
||
|
||
/**
|
||
* Matches values that are less than or equal to the value specified in the query.
|
||
*
|
||
* @param a
|
||
* @param b
|
||
* @returns {boolean}
|
||
*/
|
||
function $lte (a, b) {
|
||
return compare$1(a, b, (x,y) => x <= y)
|
||
}
|
||
|
||
/**
|
||
* Matches values that are greater than the value specified in the query.
|
||
*
|
||
* @param a
|
||
* @param b
|
||
* @returns {boolean}
|
||
*/
|
||
function $gt (a, b) {
|
||
return compare$1(a, b, (x,y) => x > y)
|
||
}
|
||
|
||
/**
|
||
* Matches values that are greater than or equal to the value specified in the query.
|
||
*
|
||
* @param a
|
||
* @param b
|
||
* @returns {boolean}
|
||
*/
|
||
function $gte (a, b) {
|
||
return compare$1(a, b, (x,y) => x >= y)
|
||
}
|
||
|
||
/**
|
||
* Performs a modulo operation on the value of a field and selects documents with a specified result.
|
||
*
|
||
* @param a
|
||
* @param b
|
||
* @returns {boolean}
|
||
*/
|
||
function $mod$1 (a, b) {
|
||
return ensureArray(a).some(x => isNumber(x) && isArray(b) && b.length === 2 && (x % b[0]) === b[1])
|
||
}
|
||
|
||
/**
|
||
* Selects documents where values match a specified regular expression.
|
||
*
|
||
* @param a
|
||
* @param b
|
||
* @returns {boolean}
|
||
*/
|
||
function $regex (a, b) {
|
||
a = ensureArray(a);
|
||
let match = (x => isString(x) && !!x.match(b));
|
||
return a.some(match) || flatten(a, 1).some(match)
|
||
}
|
||
|
||
/**
|
||
* Matches documents that have the specified field.
|
||
*
|
||
* @param a
|
||
* @param b
|
||
* @returns {boolean}
|
||
*/
|
||
function $exists (a, b) {
|
||
return ((b === false || b === 0) && a === undefined) || ((b === true || b === 1) && a !== undefined)
|
||
}
|
||
|
||
/**
|
||
* Matches arrays that contain all elements specified in the query.
|
||
*
|
||
* @param a
|
||
* @param b
|
||
* @returns boolean
|
||
*/
|
||
function $all (a, b) {
|
||
let matched = false;
|
||
if (isArray(a) && isArray(b)) {
|
||
for (let i = 0, len = b.length; i < len; i++) {
|
||
if (isObject(b[i]) && inArray(keys(b[i]), '$elemMatch')) {
|
||
matched = matched || $elemMatch(a, b[i].$elemMatch);
|
||
} else {
|
||
// order of arguments matter
|
||
return intersection(b, a).length === len
|
||
}
|
||
}
|
||
}
|
||
return matched
|
||
}
|
||
|
||
/**
|
||
* Selects documents if the array field is a specified size.
|
||
*
|
||
* @param a
|
||
* @param b
|
||
* @returns {*|boolean}
|
||
*/
|
||
function $size$1 (a, b) {
|
||
return isArray(a) && isNumber(b) && (a.length === b)
|
||
}
|
||
|
||
/**
|
||
* Selects documents if element in the array field matches all the specified $elemMatch condition.
|
||
*
|
||
* @param a {Array} element to match against
|
||
* @param b {Object} subquery
|
||
*/
|
||
function $elemMatch (a, b) {
|
||
if (isArray(a) && !isEmpty(a)) {
|
||
let format = x => x;
|
||
let criteria = b;
|
||
|
||
// If we find an operator in the subquery, we fake a field to point to it.
|
||
// This is an attempt to ensure that it a valid criteria.
|
||
if (keys(b).every(isOperator)) {
|
||
criteria = { temp: b };
|
||
format = x => ({ temp: x });
|
||
}
|
||
let query = new Query(criteria);
|
||
for (let i = 0, len = a.length; i < len; i++) {
|
||
if (query.test(format(a[i]))) {
|
||
return true
|
||
}
|
||
}
|
||
}
|
||
return false
|
||
}
|
||
|
||
/**
|
||
* Selects documents if a field is of the specified type.
|
||
*
|
||
* @param a
|
||
* @param b
|
||
* @returns {boolean}
|
||
*/
|
||
function $type (a, b) {
|
||
switch (b) {
|
||
case 1:
|
||
case 'double':
|
||
return isNumber(a) && (a + '').indexOf('.') !== -1
|
||
case 2:
|
||
case T_STRING:
|
||
return isString(a)
|
||
case 3:
|
||
case T_OBJECT:
|
||
return isObject(a)
|
||
case 4:
|
||
case T_ARRAY:
|
||
return isArray(a)
|
||
case 6:
|
||
case T_UNDEFINED:
|
||
return isNil(a)
|
||
case 8:
|
||
case T_BOOL:
|
||
return isBoolean(a)
|
||
case 9:
|
||
case T_DATE:
|
||
return isDate(a)
|
||
case 10:
|
||
case T_NULL:
|
||
return isNull(a)
|
||
case 11:
|
||
case T_REGEX:
|
||
return isRegExp(a)
|
||
case 16:
|
||
case 'int':
|
||
return isNumber(a) && a <= 2147483647 && (a + '').indexOf('.') === -1
|
||
case 18:
|
||
case 'long':
|
||
return isNumber(a) && a > 2147483647 && a <= 9223372036854775807 && (a + '').indexOf('.') === -1
|
||
case 19:
|
||
case 'decimal':
|
||
return isNumber(a)
|
||
default:
|
||
return false
|
||
}
|
||
}
|
||
|
||
function compare$1(a, b, f) {
|
||
return ensureArray(a).some(x => getType(x) === getType(b) && f(x,b))
|
||
}
|
||
|
||
function createComparison (f) {
|
||
return (obj, expr) => {
|
||
let args = computeValue(obj, expr);
|
||
return f(args[0], args[1])
|
||
}
|
||
}
|
||
|
||
const $eq$1 = createComparison($eq);
|
||
const $ne$1 = createComparison($ne);
|
||
const $gt$1 = createComparison($gt);
|
||
const $lt$1 = createComparison($lt);
|
||
const $gte$1 = createComparison($gte);
|
||
const $lte$1 = createComparison($lte);
|
||
const $nin$1 = createComparison($nin);
|
||
|
||
/**
|
||
* Compares two values and returns the result of the comparison as an integer.
|
||
*
|
||
* @param obj
|
||
* @param expr
|
||
* @returns {number}
|
||
*/
|
||
function $cmp (obj, expr) {
|
||
let args = computeValue(obj, expr);
|
||
if (args[0] > args[1]) return 1
|
||
if (args[0] < args[1]) return -1
|
||
return 0
|
||
}
|
||
|
||
/**
|
||
* Conditional operators
|
||
*/
|
||
|
||
/**
|
||
* A ternary operator that evaluates one expression,
|
||
* and depending on the result returns the value of one following expressions.
|
||
*
|
||
* @param obj
|
||
* @param expr
|
||
*/
|
||
function $cond (obj, expr) {
|
||
let ifExpr, thenExpr, elseExpr;
|
||
const errorMsg = '$cond: invalid arguments';
|
||
if (isArray(expr)) {
|
||
assert(expr.length === 3, errorMsg);
|
||
ifExpr = expr[0];
|
||
thenExpr = expr[1];
|
||
elseExpr = expr[2];
|
||
} else {
|
||
assert(isObject(expr), errorMsg);
|
||
ifExpr = expr['if'];
|
||
thenExpr = expr['then'];
|
||
elseExpr = expr['else'];
|
||
}
|
||
let condition = computeValue(obj, ifExpr);
|
||
return condition ? computeValue(obj, thenExpr) : computeValue(obj, elseExpr)
|
||
}
|
||
|
||
/**
|
||
* An operator that evaluates a series of case expressions. When it finds an expression which
|
||
* evaluates to true, it returns the resulting expression for that case. If none of the cases
|
||
* evaluate to true, it returns the default expression.
|
||
*
|
||
* @param obj
|
||
* @param expr
|
||
*/
|
||
function $switch (obj, expr) {
|
||
const errorMsg = 'Invalid arguments for $switch operator';
|
||
assert(expr.branches, errorMsg);
|
||
|
||
let validBranch = expr.branches.find((branch) => {
|
||
assert(branch['case'] && branch['then'], errorMsg);
|
||
return computeValue(obj, branch['case'])
|
||
});
|
||
|
||
if (validBranch) {
|
||
return computeValue(obj, validBranch.then)
|
||
} else {
|
||
assert(expr['default'], errorMsg);
|
||
return computeValue(obj, expr.default)
|
||
}
|
||
}
|
||
|
||
/**
|
||
* Evaluates an expression and returns the first expression if it evaluates to a non-null value.
|
||
* Otherwise, $ifNull returns the second expression's value.
|
||
*
|
||
* @param obj
|
||
* @param expr
|
||
* @returns {*}
|
||
*/
|
||
function $ifNull (obj, expr) {
|
||
assert(isArray(expr) && expr.length === 2, '$ifNull expression must resolve to array(2)');
|
||
let args = computeValue(obj, expr);
|
||
return isNil(args[0]) ? args[1] : args[0]
|
||
}
|
||
|
||
/**
|
||
* Returns the day of the year for a date as a number between 1 and 366 (leap year).
|
||
* @param obj
|
||
* @param expr
|
||
*/
|
||
function $dayOfYear (obj, expr) {
|
||
let d = computeValue(obj, expr);
|
||
let start = new Date(d.getFullYear(), 0, 0);
|
||
let diff = d - start;
|
||
let oneDay = 1000 * 60 * 60 * 24;
|
||
return Math.round(diff / oneDay)
|
||
}
|
||
|
||
/**
|
||
* Returns the day of the month for a date as a number between 1 and 31.
|
||
* @param obj
|
||
* @param expr
|
||
*/
|
||
function $dayOfMonth (obj, expr) {
|
||
let d = computeValue(obj, expr);
|
||
return d.getDate()
|
||
}
|
||
|
||
/**
|
||
* Returns the day of the week for a date as a number between 1 (Sunday) and 7 (Saturday).
|
||
* @param obj
|
||
* @param expr
|
||
*/
|
||
function $dayOfWeek (obj, expr) {
|
||
let d = computeValue(obj, expr);
|
||
return d.getDay() + 1
|
||
}
|
||
|
||
/**
|
||
* Returns the year for a date as a number (e.g. 2014).
|
||
* @param obj
|
||
* @param expr
|
||
*/
|
||
function $year (obj, expr) {
|
||
let d = computeValue(obj, expr);
|
||
return d.getFullYear()
|
||
}
|
||
|
||
/**
|
||
* Returns the month for a date as a number between 1 (January) and 12 (December).
|
||
* @param obj
|
||
* @param expr
|
||
*/
|
||
function $month (obj, expr) {
|
||
let d = computeValue(obj, expr);
|
||
return d.getMonth() + 1
|
||
}
|
||
|
||
/**
|
||
* Returns the week number for a date as a number between 0
|
||
* (the partial week that precedes the first Sunday of the year) and 53 (leap year).
|
||
* @param obj
|
||
* @param expr
|
||
*/
|
||
function $week (obj, expr) {
|
||
// source: http://stackoverflow.com/a/6117889/1370481
|
||
let d = computeValue(obj, expr);
|
||
|
||
// Copy date so don't modify original
|
||
d = new Date(+d);
|
||
d.setHours(0, 0, 0);
|
||
// Set to nearest Thursday: current date + 4 - current day number
|
||
// Make Sunday's day number 7
|
||
d.setDate(d.getDate() + 4 - (d.getDay() || 7));
|
||
// Get first day of year
|
||
let yearStart = new Date(d.getFullYear(), 0, 1);
|
||
// Calculate full weeks to nearest Thursday
|
||
return Math.floor((((d - yearStart) / 8.64e7) + 1) / 7)
|
||
}
|
||
|
||
/**
|
||
* Returns the hour for a date as a number between 0 and 23.
|
||
* @param obj
|
||
* @param expr
|
||
*/
|
||
function $hour (obj, expr) {
|
||
let d = computeValue(obj, expr);
|
||
return d.getUTCHours()
|
||
}
|
||
|
||
/**
|
||
* Returns the minute for a date as a number between 0 and 59.
|
||
* @param obj
|
||
* @param expr
|
||
*/
|
||
function $minute (obj, expr) {
|
||
let d = computeValue(obj, expr);
|
||
return d.getMinutes()
|
||
}
|
||
|
||
/**
|
||
* Returns the seconds for a date as a number between 0 and 60 (leap seconds).
|
||
* @param obj
|
||
* @param expr
|
||
*/
|
||
function $second (obj, expr) {
|
||
let d = computeValue(obj, expr);
|
||
return d.getSeconds()
|
||
}
|
||
|
||
/**
|
||
* Returns the milliseconds of a date as a number between 0 and 999.
|
||
* @param obj
|
||
* @param expr
|
||
*/
|
||
function $millisecond (obj, expr) {
|
||
let d = computeValue(obj, expr);
|
||
return d.getMilliseconds()
|
||
}
|
||
|
||
// used for formatting dates in $dateToString operator
|
||
const DATE_SYM_TABLE = {
|
||
'%Y': [$year, 4],
|
||
'%m': [$month, 2],
|
||
'%d': [$dayOfMonth, 2],
|
||
'%H': [$hour, 2],
|
||
'%M': [$minute, 2],
|
||
'%S': [$second, 2],
|
||
'%L': [$millisecond, 3],
|
||
'%j': [$dayOfYear, 3],
|
||
'%w': [$dayOfWeek, 1],
|
||
'%U': [$week, 2],
|
||
'%%': '%'
|
||
};
|
||
|
||
/**
|
||
* Returns the date as a formatted string.
|
||
*
|
||
* %Y Year (4 digits, zero padded) 0000-9999
|
||
* %m Month (2 digits, zero padded) 01-12
|
||
* %d Day of Month (2 digits, zero padded) 01-31
|
||
* %H Hour (2 digits, zero padded, 24-hour clock) 00-23
|
||
* %M Minute (2 digits, zero padded) 00-59
|
||
* %S Second (2 digits, zero padded) 00-60
|
||
* %L Millisecond (3 digits, zero padded) 000-999
|
||
* %j Day of year (3 digits, zero padded) 001-366
|
||
* %w Day of week (1-Sunday, 7-Saturday) 1-7
|
||
* %U Week of year (2 digits, zero padded) 00-53
|
||
* %% Percent Character as a Literal %
|
||
*
|
||
* @param obj current object
|
||
* @param expr operator expression
|
||
*/
|
||
function $dateToString (obj, expr) {
|
||
let fmt = expr['format'];
|
||
let date = computeValue(obj, expr['date']);
|
||
let matches = fmt.match(/(%%|%Y|%m|%d|%H|%M|%S|%L|%j|%w|%U)/g);
|
||
|
||
for (let i = 0, len = matches.length; i < len; i++) {
|
||
let hdlr = DATE_SYM_TABLE[matches[i]];
|
||
let value = hdlr;
|
||
|
||
if (isArray(hdlr)) {
|
||
// reuse date operators
|
||
let fn = hdlr[0];
|
||
let pad = hdlr[1];
|
||
value = padDigits(fn(obj, date), pad);
|
||
}
|
||
// replace the match with resolved value
|
||
fmt = fmt.replace(matches[i], value);
|
||
}
|
||
|
||
return fmt
|
||
}
|
||
|
||
function padDigits (number, digits) {
|
||
return new Array(Math.max(digits - String(number).length + 1, 0)).join('0') + number
|
||
}
|
||
|
||
/**
|
||
* Return a value without parsing.
|
||
* @param obj
|
||
* @param expr
|
||
*/
|
||
function $literal (obj, expr) {
|
||
return expr
|
||
}
|
||
|
||
/**
|
||
* Returns true if two sets have the same elements.
|
||
* @param obj
|
||
* @param expr
|
||
*/
|
||
function $setEquals (obj, expr) {
|
||
let args = computeValue(obj, expr);
|
||
let xs = unique(args[0]);
|
||
let ys = unique(args[1]);
|
||
return xs.length === ys.length && xs.length === intersection(xs, ys).length
|
||
}
|
||
|
||
/**
|
||
* Returns the common elements of the input sets.
|
||
* @param obj
|
||
* @param expr
|
||
*/
|
||
function $setIntersection (obj, expr) {
|
||
let args = computeValue(obj, expr);
|
||
return intersection(args[0], args[1])
|
||
}
|
||
|
||
/**
|
||
* Returns elements of a set that do not appear in a second set.
|
||
* @param obj
|
||
* @param expr
|
||
*/
|
||
function $setDifference (obj, expr) {
|
||
let args = computeValue(obj, expr);
|
||
return args[0].filter(notInArray.bind(null, args[1]))
|
||
}
|
||
|
||
/**
|
||
* Returns a set that holds all elements of the input sets.
|
||
* @param obj
|
||
* @param expr
|
||
*/
|
||
function $setUnion (obj, expr) {
|
||
let args = computeValue(obj, expr);
|
||
return union(args[0], args[1])
|
||
}
|
||
|
||
/**
|
||
* Returns true if all elements of a set appear in a second set.
|
||
* @param obj
|
||
* @param expr
|
||
*/
|
||
function $setIsSubset (obj, expr) {
|
||
let args = computeValue(obj, expr);
|
||
return intersection(args[0], args[1]).length === args[0].length
|
||
}
|
||
|
||
/**
|
||
* Returns true if any elements of a set evaluate to true, and false otherwise.
|
||
* @param obj
|
||
* @param expr
|
||
*/
|
||
function $anyElementTrue (obj, expr) {
|
||
// mongodb nests the array expression in another
|
||
let args = computeValue(obj, expr)[0];
|
||
return args.some(truthy)
|
||
}
|
||
|
||
/**
|
||
* Returns true if all elements of a set evaluate to true, and false otherwise.
|
||
* @param obj
|
||
* @param expr
|
||
*/
|
||
function $allElementsTrue (obj, expr) {
|
||
// mongodb nests the array expression in another
|
||
let args = computeValue(obj, expr)[0];
|
||
return args.every(truthy)
|
||
}
|
||
|
||
/**
|
||
* Concatenates two strings.
|
||
*
|
||
* @param obj
|
||
* @param expr
|
||
* @returns {string|*}
|
||
*/
|
||
function $concat (obj, expr) {
|
||
let args = computeValue(obj, expr);
|
||
// does not allow concatenation with nulls
|
||
if ([null, undefined].some(inArray.bind(null, args))) return null
|
||
return args.join('')
|
||
}
|
||
|
||
/**
|
||
* Searches a string for an occurrence of a substring and returns the UTF-8 code point index of the first occurence.
|
||
* If the substring is not found, returns -1.
|
||
*
|
||
* @param {Object} obj
|
||
* @param {*} expr
|
||
* @return {*}
|
||
*/
|
||
function $indexOfBytes (obj, expr) {
|
||
let arr = computeValue(obj, expr);
|
||
const errorMsg = '$indexOfBytes expression resolves to invalid an argument';
|
||
|
||
if (isNil(arr[0])) return null
|
||
|
||
assert(isString(arr[0]) && isString(arr[1]), errorMsg);
|
||
|
||
let str = arr[0];
|
||
let searchStr = arr[1];
|
||
let start = arr[2];
|
||
let end = arr[3];
|
||
|
||
let valid = isNil(start) || (isNumber(start) && start >= 0 && Math.round(start) === start);
|
||
valid = valid && (isNil(end) || (isNumber(end) && end >= 0 && Math.round(end) === end));
|
||
assert(valid, errorMsg);
|
||
|
||
start = start || 0;
|
||
end = end || str.length;
|
||
|
||
if (start > end) return -1
|
||
|
||
let index = str.substring(start, end).indexOf(searchStr);
|
||
return (index > -1)
|
||
? index + start
|
||
: index
|
||
}
|
||
|
||
/**
|
||
* Splits a string into substrings based on a delimiter.
|
||
* If the delimiter is not found within the string, returns an array containing the original string.
|
||
*
|
||
* @param {Object} obj
|
||
* @param {Array} expr
|
||
* @return {Array} Returns an array of substrings.
|
||
*/
|
||
function $split (obj, expr) {
|
||
let args = computeValue(obj, expr);
|
||
if (isNil(args[0])) return null
|
||
assert(args.every(isString), '$split expression must result to array(2) of strings');
|
||
return args[0].split(args[1])
|
||
}
|
||
|
||
/**
|
||
* Returns the number of UTF-8 encoded bytes in the specified string.
|
||
*
|
||
* @param {Object} obj
|
||
* @param {String} expr
|
||
* @return {Number}
|
||
*/
|
||
function $strLenBytes (obj, expr) {
|
||
return ~-encodeURI(computeValue(obj, expr)).split(/%..|./).length
|
||
}
|
||
|
||
/**
|
||
* Returns the number of UTF-8 code points in the specified string.
|
||
*
|
||
* @param {Object} obj
|
||
* @param {String} expr
|
||
* @return {Number}
|
||
*/
|
||
function $strLenCP (obj, expr) {
|
||
return computeValue(obj, expr).length
|
||
}
|
||
|
||
/**
|
||
* Compares two strings and returns an integer that reflects the comparison.
|
||
*
|
||
* @param obj
|
||
* @param expr
|
||
* @returns {number}
|
||
*/
|
||
function $strcasecmp (obj, expr) {
|
||
let args = computeValue(obj, expr);
|
||
let a = args[0];
|
||
let b = args[1];
|
||
if (isEqual(a, b) || args.every(isNil)) return 0
|
||
assert(args.every(isString), '$strcasecmp must resolve to array(2) of strings');
|
||
a = a.toUpperCase();
|
||
b = b.toUpperCase();
|
||
return (a > b && 1) || (a < b && -1) || 0
|
||
}
|
||
|
||
/**
|
||
* Returns a substring of a string, starting at a specified index position and including the specified number of characters.
|
||
* The index is zero-based.
|
||
*
|
||
* @param obj
|
||
* @param expr
|
||
* @returns {string}
|
||
*/
|
||
function $substrBytes (obj, expr) {
|
||
let args = computeValue(obj, expr);
|
||
let s = args[0];
|
||
let index = args[1];
|
||
let count = args[2];
|
||
assert(isString(s) && isNumber(index) && index >= 0 && isNumber(count) && count >= 0, '$substrBytes: invalid arguments');
|
||
let buf = utf8Encode(s);
|
||
let validIndex = [];
|
||
let acc = 0;
|
||
for (let i = 0; i < buf.length; i++) {
|
||
validIndex.push(acc);
|
||
acc += buf[i].length;
|
||
}
|
||
let begin = validIndex.indexOf(index);
|
||
let end = validIndex.indexOf(index + count);
|
||
assert(begin > -1 && end > -1, '$substrBytes: invalid range, start or end index is a UTF-8 continuation byte.');
|
||
return s.substring(begin, end)
|
||
}
|
||
|
||
/**
|
||
* Returns a substring of a string, starting at a specified index position and including the specified number of characters.
|
||
* The index is zero-based.
|
||
*
|
||
* @param obj
|
||
* @param expr
|
||
* @returns {string}
|
||
*/
|
||
function $substr (obj, expr) {
|
||
let args = computeValue(obj, expr);
|
||
let s = args[0];
|
||
let index = args[1];
|
||
let count = args[2];
|
||
if (isString(s)) {
|
||
if (index < 0) {
|
||
return ''
|
||
} else if (count < 0) {
|
||
return s.substr(index)
|
||
} else {
|
||
return s.substr(index, count)
|
||
}
|
||
}
|
||
return ''
|
||
}
|
||
|
||
function $substrCP (obj, expr) {
|
||
return $substr(obj, expr)
|
||
}
|
||
|
||
/**
|
||
* Converts a string to lowercase.
|
||
*
|
||
* @param obj
|
||
* @param expr
|
||
* @returns {string}
|
||
*/
|
||
function $toLower (obj, expr) {
|
||
let value = computeValue(obj, expr);
|
||
return isEmpty(value) ? '' : value.toLowerCase()
|
||
}
|
||
|
||
/**
|
||
* Converts a string to uppercase.
|
||
*
|
||
* @param obj
|
||
* @param expr
|
||
* @returns {string}
|
||
*/
|
||
function $toUpper (obj, expr) {
|
||
let value = computeValue(obj, expr);
|
||
return isEmpty(value) ? '' : value.toUpperCase()
|
||
}
|
||
|
||
const UTF8_MASK = [0xC0, 0xE0, 0xF0];
|
||
// encodes a unicode code point to a utf8 byte sequence
|
||
// https://encoding.spec.whatwg.org/#utf-8
|
||
function toUtf8 (n) {
|
||
if (n < 0x80) return [n]
|
||
let count = ((n < 0x0800) && 1) || ((n < 0x10000) && 2) || 3;
|
||
const offset = UTF8_MASK[count - 1];
|
||
let utf8 = [(n >> (6 * count)) + offset];
|
||
while (count > 0) utf8.push(0x80 | ((n >> (6 * --count)) & 0x3F));
|
||
return utf8
|
||
}
|
||
|
||
function utf8Encode(s) {
|
||
let buf = [];
|
||
for (let i = 0, len = s.length; i < len; i++) {
|
||
buf.push(toUtf8(s.codePointAt(i)));
|
||
}
|
||
return buf
|
||
}
|
||
|
||
/**
|
||
* Aggregation framework variable operators
|
||
*/
|
||
|
||
/**
|
||
* Defines variables for use within the scope of a sub-expression and returns the result of the sub-expression.
|
||
*
|
||
* @param obj
|
||
* @param expr
|
||
* @returns {*}
|
||
*/
|
||
function $let (obj, expr) {
|
||
let varsExpr = expr['vars'];
|
||
let inExpr = expr['in'];
|
||
|
||
// resolve vars
|
||
let varsKeys = keys(varsExpr);
|
||
each(varsKeys, key => {
|
||
let val = computeValue(obj, varsExpr[key]);
|
||
let tempKey = '$' + key;
|
||
obj[tempKey] = val;
|
||
});
|
||
|
||
return computeValue(obj, inExpr)
|
||
}
|
||
|
||
var expressionOperators = /*#__PURE__*/Object.freeze({
|
||
__proto__: null,
|
||
$abs: $abs,
|
||
$add: $add,
|
||
$ceil: $ceil,
|
||
$divide: $divide,
|
||
$exp: $exp,
|
||
$floor: $floor,
|
||
$ln: $ln,
|
||
$log: $log,
|
||
$log10: $log10,
|
||
$mod: $mod,
|
||
$multiply: $multiply,
|
||
$pow: $pow,
|
||
$round: $round,
|
||
$sqrt: $sqrt,
|
||
$subtract: $subtract,
|
||
$trunc: $trunc,
|
||
$arrayElemAt: $arrayElemAt,
|
||
$arrayToObject: $arrayToObject,
|
||
$concatArrays: $concatArrays,
|
||
$filter: $filter,
|
||
$in: $in,
|
||
$indexOfArray: $indexOfArray,
|
||
$isArray: $isArray,
|
||
$map: $map,
|
||
$objectToArray: $objectToArray,
|
||
$range: $range,
|
||
$reduce: $reduce,
|
||
$reverseArray: $reverseArray,
|
||
$size: $size,
|
||
$slice: $slice,
|
||
$zip: $zip,
|
||
$mergeObjects: $mergeObjects,
|
||
$and: $and,
|
||
$or: $or,
|
||
$not: $not,
|
||
$eq: $eq$1,
|
||
$ne: $ne$1,
|
||
$gt: $gt$1,
|
||
$lt: $lt$1,
|
||
$gte: $gte$1,
|
||
$lte: $lte$1,
|
||
$nin: $nin$1,
|
||
$cmp: $cmp,
|
||
$cond: $cond,
|
||
$switch: $switch,
|
||
$ifNull: $ifNull,
|
||
$dayOfYear: $dayOfYear,
|
||
$dayOfMonth: $dayOfMonth,
|
||
$dayOfWeek: $dayOfWeek,
|
||
$year: $year,
|
||
$month: $month,
|
||
$week: $week,
|
||
$hour: $hour,
|
||
$minute: $minute,
|
||
$second: $second,
|
||
$millisecond: $millisecond,
|
||
$dateToString: $dateToString,
|
||
$literal: $literal,
|
||
$setEquals: $setEquals,
|
||
$setIntersection: $setIntersection,
|
||
$setDifference: $setDifference,
|
||
$setUnion: $setUnion,
|
||
$setIsSubset: $setIsSubset,
|
||
$anyElementTrue: $anyElementTrue,
|
||
$allElementsTrue: $allElementsTrue,
|
||
$concat: $concat,
|
||
$indexOfBytes: $indexOfBytes,
|
||
$split: $split,
|
||
$strLenBytes: $strLenBytes,
|
||
$strLenCP: $strLenCP,
|
||
$strcasecmp: $strcasecmp,
|
||
$substrBytes: $substrBytes,
|
||
$substr: $substr,
|
||
$substrCP: $substrCP,
|
||
$toLower: $toLower,
|
||
$toUpper: $toUpper,
|
||
$let: $let
|
||
});
|
||
|
||
/**
|
||
* Returns an array of all values for the selected field among for each document in that group.
|
||
*
|
||
* @param collection
|
||
* @param expr
|
||
* @returns {Array|*}
|
||
*/
|
||
function $push (collection, expr) {
|
||
if (isNil(expr)) return collection
|
||
return collection.map(obj => computeValue(obj, expr))
|
||
}
|
||
|
||
/**
|
||
* Returns an array of all the unique values for the selected field among for each document in that group.
|
||
*
|
||
* @param collection
|
||
* @param expr
|
||
* @returns {*}
|
||
*/
|
||
function $addToSet (collection, expr) {
|
||
return unique($push(collection, expr))
|
||
}
|
||
|
||
/**
|
||
* Returns an average of all the values in a group.
|
||
*
|
||
* @param collection
|
||
* @param expr
|
||
* @returns {number}
|
||
*/
|
||
function $avg (collection, expr) {
|
||
let data = $push(collection, expr).filter(isNumber);
|
||
let sum = reduce(data, (acc, n) => acc + n, 0);
|
||
return sum / (data.length || 1)
|
||
}
|
||
|
||
/**
|
||
* Returns the first value in a group.
|
||
*
|
||
* @param collection
|
||
* @param expr
|
||
* @returns {*}
|
||
*/
|
||
function $first (collection, expr) {
|
||
return collection.length > 0 ? computeValue(collection[0], expr) : undefined
|
||
}
|
||
|
||
/**
|
||
* Returns the last value in a group.
|
||
*
|
||
* @param collection
|
||
* @param expr
|
||
* @returns {*}
|
||
*/
|
||
function $last (collection, expr) {
|
||
return collection.length > 0 ? computeValue(collection[collection.length - 1], expr) : undefined
|
||
}
|
||
|
||
/**
|
||
* Returns the highest value in a group.
|
||
*
|
||
* @param collection
|
||
* @param expr
|
||
* @returns {*}
|
||
*/
|
||
function $max (collection, expr) {
|
||
return reduce($push(collection, expr), (acc, n) => (isNil(acc) || n > acc) ? n : acc, undefined)
|
||
}
|
||
|
||
/**
|
||
* Combines multiple documents into a single document.
|
||
*
|
||
* @param collection
|
||
* @param expr
|
||
* @returns {Array|*}
|
||
*/
|
||
function $mergeObjects$1 (collection, expr) {
|
||
return reduce(collection, (memo, o) => Object.assign(memo, computeValue(o, expr)), {})
|
||
}
|
||
|
||
/**
|
||
* Returns the lowest value in a group.
|
||
*
|
||
* @param collection
|
||
* @param expr
|
||
* @returns {*}
|
||
*/
|
||
function $min (collection, expr) {
|
||
return reduce($push(collection, expr), (acc, n) => (isNil(acc) || n < acc) ? n : acc, undefined)
|
||
}
|
||
|
||
/**
|
||
* Returns the population standard deviation of the input values.
|
||
*
|
||
* @param {Array} collection
|
||
* @param {Object} expr
|
||
* @return {Number}
|
||
*/
|
||
function $stdDevPop (collection, expr) {
|
||
return stddev($push(collection, expr).filter(isNumber), false)
|
||
}
|
||
|
||
/**
|
||
* Returns the sample standard deviation of the input values.
|
||
* @param {Array} collection
|
||
* @param {Object} expr
|
||
* @return {Number|null}
|
||
*/
|
||
function $stdDevSamp (collection, expr) {
|
||
return stddev($push(collection, expr).filter(isNumber), true)
|
||
}
|
||
|
||
/**
|
||
* Returns the sum of all the values in a group.
|
||
*
|
||
* @param collection
|
||
* @param expr
|
||
* @returns {*}
|
||
*/
|
||
function $sum (collection, expr) {
|
||
if (!isArray(collection)) return 0
|
||
|
||
// take a short cut if expr is number literal
|
||
if (isNumber(expr)) return collection.length * expr
|
||
|
||
return reduce($push(collection, expr).filter(isNumber), (acc, n) => acc + n, 0)
|
||
}
|
||
|
||
/**
|
||
* Group stage Accumulator Operators. https://docs.mongodb.com/manual/reference/operator/aggregation-
|
||
*/
|
||
|
||
var groupOperators = /*#__PURE__*/Object.freeze({
|
||
__proto__: null,
|
||
$addToSet: $addToSet,
|
||
$avg: $avg,
|
||
$first: $first,
|
||
$last: $last,
|
||
$max: $max,
|
||
$mergeObjects: $mergeObjects$1,
|
||
$min: $min,
|
||
$push: $push,
|
||
$stdDevPop: $stdDevPop,
|
||
$stdDevSamp: $stdDevSamp,
|
||
$sum: $sum
|
||
});
|
||
|
||
/**
|
||
* Adds new fields to documents.
|
||
* Outputs documents that contain all existing fields from the input documents and newly added fields.
|
||
*
|
||
* @param {Array} collection
|
||
* @param {*} expr
|
||
* @param {Object} opt Pipeline options
|
||
*/
|
||
function $addFields (collection, expr, opt) {
|
||
let newFields = keys(expr);
|
||
|
||
if (newFields.length === 0) return collection
|
||
|
||
return collection.map(obj => {
|
||
let newObj = cloneDeep(obj);
|
||
each(newFields, (field) => {
|
||
let newValue = computeValue(obj, expr[field]);
|
||
setValue(newObj, field, newValue);
|
||
});
|
||
return newObj
|
||
})
|
||
}
|
||
|
||
/**
|
||
* Alias for $addFields.
|
||
*/
|
||
const $set = $addFields;
|
||
|
||
/**
|
||
* Categorizes incoming documents into groups, called buckets, based on a specified expression and bucket boundaries.
|
||
* https://docs.mongodb.com/manual/reference/operator/aggregation/bucket/
|
||
*
|
||
* @param {*} collection
|
||
* @param {*} expr
|
||
* @param {Object} opt Pipeline options
|
||
*/
|
||
function $bucket (collection, expr, opt) {
|
||
let boundaries = expr.boundaries;
|
||
let defaultKey = expr['default'];
|
||
let lower = boundaries[0]; // inclusive
|
||
let upper = boundaries[boundaries.length - 1]; // exclusive
|
||
let outputExpr = expr.output || { 'count': { '$sum': 1 } };
|
||
|
||
assert(boundaries.length > 2, "$bucket 'boundaries' expression must have at least 3 elements");
|
||
let boundType = getType(lower);
|
||
|
||
for (let i = 0, len = boundaries.length - 1; i < len; i++) {
|
||
assert(boundType === getType(boundaries[i + 1]), "$bucket 'boundaries' must all be of the same type");
|
||
assert(boundaries[i] < boundaries[i + 1], "$bucket 'boundaries' must be sorted in ascending order");
|
||
}
|
||
|
||
!isNil(defaultKey)
|
||
&& (getType(expr.default) === getType(lower))
|
||
&& assert(lower > expr.default || upper < expr.default, "$bucket 'default' expression must be out of boundaries range");
|
||
|
||
let grouped = {};
|
||
each(boundaries, (k) => grouped[k] = []);
|
||
|
||
// add default key if provided
|
||
if (!isNil(defaultKey)) grouped[defaultKey] = [];
|
||
|
||
let iterator = false;
|
||
|
||
return Lazy(() => {
|
||
if (!iterator) {
|
||
collection.each(obj => {
|
||
let key = computeValue(obj, expr.groupBy);
|
||
|
||
if (isNil(key) || key < lower || key >= upper) {
|
||
assert(!isNil(defaultKey), '$bucket require a default for out of range values');
|
||
grouped[defaultKey].push(obj);
|
||
} else {
|
||
assert(key >= lower && key < upper, "$bucket 'groupBy' expression must resolve to a value in range of boundaries");
|
||
let index = findInsertIndex(boundaries, key);
|
||
let boundKey = boundaries[Math.max(0, index - 1)];
|
||
grouped[boundKey].push(obj);
|
||
}
|
||
});
|
||
|
||
// upper bound is exclusive so we remove it
|
||
boundaries.pop();
|
||
if (!isNil(defaultKey)) boundaries.push(defaultKey);
|
||
|
||
iterator = Lazy(boundaries).map(key => {
|
||
let acc = accumulate(grouped[key], null, outputExpr);
|
||
return Object.assign(acc, { '_id': key })
|
||
});
|
||
}
|
||
return iterator.next()
|
||
})
|
||
}
|
||
|
||
/**
|
||
* Categorizes incoming documents into a specific number of groups, called buckets,
|
||
* based on a specified expression. Bucket boundaries are automatically determined
|
||
* in an attempt to evenly distribute the documents into the specified number of buckets.
|
||
* https://docs.mongodb.com/manual/reference/operator/aggregation/bucketAuto/
|
||
*
|
||
* @param {*} collection
|
||
* @param {*} expr
|
||
* @param {*} opt Pipeline options
|
||
*/
|
||
function $bucketAuto (collection, expr, opt) {
|
||
let outputExpr = expr.output || { 'count': { '$sum': 1 } };
|
||
let groupByExpr = expr.groupBy;
|
||
let bucketCount = expr.buckets;
|
||
|
||
assert(bucketCount > 0, "The $bucketAuto 'buckets' field must be greater than 0, but found: " + bucketCount);
|
||
|
||
return collection.transform(coll => {
|
||
let approxBucketSize = Math.max(1, Math.round(coll.length / bucketCount));
|
||
let computeValueOptimized = memoize(computeValue);
|
||
let grouped = {};
|
||
let remaining = [];
|
||
|
||
let sorted = sortBy(coll, o => {
|
||
let key = computeValueOptimized(o, groupByExpr);
|
||
if (isNil(key)) {
|
||
remaining.push(o);
|
||
} else {
|
||
grouped[key] || (grouped[key] = []);
|
||
grouped[key].push(o);
|
||
}
|
||
return key
|
||
});
|
||
|
||
const ID_KEY = idKey();
|
||
let result = [];
|
||
let index = 0; // counter for sorted collection
|
||
|
||
for (let i = 0, len = sorted.length; i < bucketCount && index < len; i++) {
|
||
let boundaries = {};
|
||
let bucketItems = [];
|
||
|
||
for (let j = 0; j < approxBucketSize && index < len; j++) {
|
||
let key = computeValueOptimized(sorted[index], groupByExpr);
|
||
|
||
if (isNil(key)) key = null;
|
||
|
||
// populate current bucket with all values for current key
|
||
into(bucketItems, isNil(key) ? remaining : grouped[key]);
|
||
|
||
// increase sort index by number of items added
|
||
index += (isNil(key) ? remaining.length : grouped[key].length);
|
||
|
||
// set the min key boundary if not already present
|
||
if (!has(boundaries, 'min')) boundaries.min = key;
|
||
|
||
if (result.length > 0) {
|
||
let lastBucket = result[result.length - 1];
|
||
lastBucket[ID_KEY].max = boundaries.min;
|
||
}
|
||
}
|
||
|
||
// if is last bucket add remaining items
|
||
if (i == bucketCount - 1) {
|
||
into(bucketItems, sorted.slice(index));
|
||
}
|
||
|
||
result.push(Object.assign(accumulate(bucketItems, null, outputExpr), { '_id': boundaries }));
|
||
}
|
||
|
||
if (result.length > 0) {
|
||
result[result.length - 1][ID_KEY].max = computeValueOptimized(sorted[sorted.length - 1], groupByExpr);
|
||
}
|
||
|
||
return result
|
||
})
|
||
}
|
||
|
||
/**
|
||
* Returns a document that contains a count of the number of documents input to the stage.
|
||
*
|
||
* @param {Array} collection
|
||
* @param {String} expr
|
||
* @param {Object} opt Pipeline options
|
||
* @return {Object}
|
||
*/
|
||
function $count (collection, expr, opt) {
|
||
assert(
|
||
isString(expr) && expr.trim() !== '' && expr.indexOf('.') === -1 && expr.trim()[0] !== '$',
|
||
'Invalid expression value for $count'
|
||
);
|
||
|
||
return Lazy(() => {
|
||
let o = {};
|
||
o[expr] = collection.size();
|
||
return { value: o, done: false }
|
||
}).first()
|
||
}
|
||
|
||
/**
|
||
* Processes multiple aggregation pipelines within a single stage on the same set of input documents.
|
||
* Enables the creation of multi-faceted aggregations capable of characterizing data across multiple dimensions, or facets, in a single stage.
|
||
*/
|
||
function $facet (collection, expr, opt) {
|
||
return collection.transform(array => {
|
||
return [ objectMap(expr, pipeline => aggregate(array, pipeline)) ]
|
||
})
|
||
}
|
||
|
||
/**
|
||
* Groups documents together for the purpose of calculating aggregate values based on a collection of documents.
|
||
*
|
||
* @param collection
|
||
* @param expr
|
||
* @param opt Pipeline options
|
||
* @returns {Array}
|
||
*/
|
||
function $group (collection, expr, opt) {
|
||
// lookup key for grouping
|
||
const ID_KEY = idKey();
|
||
let id = expr[ID_KEY];
|
||
|
||
return collection.transform(coll => {
|
||
let partitions = groupBy(coll, obj => computeValue(obj, id, id));
|
||
|
||
// remove the group key
|
||
expr = clone(expr);
|
||
delete expr[ID_KEY];
|
||
|
||
let i = -1;
|
||
let size = partitions.keys.length;
|
||
|
||
return () => {
|
||
|
||
if (++i === size) return { done: true }
|
||
|
||
let value = partitions.keys[i];
|
||
let obj = {};
|
||
|
||
// exclude undefined key value
|
||
if (value !== undefined) {
|
||
obj[ID_KEY] = value;
|
||
}
|
||
|
||
// compute remaining keys in expression
|
||
each(expr, (val, key) => {
|
||
obj[key] = accumulate(partitions.groups[i], key, val);
|
||
});
|
||
|
||
return { value: obj, done: false }
|
||
}
|
||
})
|
||
}
|
||
|
||
/**
|
||
* Restricts the number of documents in an aggregation pipeline.
|
||
*
|
||
* @param collection
|
||
* @param value
|
||
* @param opt
|
||
* @returns {Object|*}
|
||
*/
|
||
function $limit (collection, value, opt) {
|
||
return collection.take(value)
|
||
}
|
||
|
||
/**
|
||
* Performs a left outer join to another collection in the same database to filter in documents from the “joined” collection for processing.
|
||
*
|
||
* @param collection
|
||
* @param expr
|
||
* @param opt
|
||
*/
|
||
function $lookup (collection, expr, opt) {
|
||
let joinColl = expr.from;
|
||
let localField = expr.localField;
|
||
let foreignField = expr.foreignField;
|
||
let asField = expr.as;
|
||
|
||
assert(isArray(joinColl) && isString(foreignField) && isString(localField) && isString(asField), '$lookup: invalid argument');
|
||
|
||
let hash = {};
|
||
|
||
each(joinColl, obj => {
|
||
let k = hashCode(resolve(obj, foreignField));
|
||
hash[k] = hash[k] || [];
|
||
hash[k].push(obj);
|
||
});
|
||
|
||
return collection.map(obj => {
|
||
let k = hashCode(resolve(obj, localField));
|
||
let newObj = clone(obj);
|
||
newObj[asField] = hash[k] || [];
|
||
return newObj
|
||
})
|
||
}
|
||
|
||
/**
|
||
* Filters the document stream, and only allows matching documents to pass into the next pipeline stage.
|
||
* $match uses standard MongoDB queries.
|
||
*
|
||
* @param collection
|
||
* @param expr
|
||
* @param opt
|
||
* @returns {Array|*}
|
||
*/
|
||
function $match (collection, expr, opt) {
|
||
let q = new Query(expr);
|
||
return collection.filter(o => q.test(o))
|
||
}
|
||
|
||
/**
|
||
* Takes the documents returned by the aggregation pipeline and writes them to a specified collection.
|
||
*
|
||
* Unlike the $out operator in MongoDB, this operator can appear in any position in the pipeline and is
|
||
* useful for collecting intermediate results of an aggregation operation.
|
||
*
|
||
* @param collection
|
||
* @param expr
|
||
* @param opt
|
||
* @returns {*}
|
||
*/
|
||
function $out (collection, expr, opt) {
|
||
assert(isArray(expr), '$out expression must be an array');
|
||
return collection.map(o => {
|
||
expr.push(o);
|
||
return o // passthrough
|
||
})
|
||
}
|
||
|
||
/**
|
||
* Reshapes a document stream.
|
||
* $project can rename, add, or remove fields as well as create computed values and sub-documents.
|
||
*
|
||
* @param collection
|
||
* @param expr
|
||
* @param opt
|
||
* @returns {Array}
|
||
*/
|
||
function $project(collection, expr, opt) {
|
||
if (isEmpty(expr)) return collection
|
||
|
||
// result collection
|
||
let expressionKeys = keys(expr);
|
||
let idOnlyExcludedExpression = false;
|
||
const ID_KEY = idKey();
|
||
|
||
// validate inclusion and exclusion
|
||
validateExpression(expr);
|
||
|
||
if (inArray(expressionKeys, ID_KEY)) {
|
||
let id = expr[ID_KEY];
|
||
if (id === 0 || id === false) {
|
||
expressionKeys = expressionKeys.filter(notInArray.bind(null, [ID_KEY]));
|
||
assert(notInArray(expressionKeys, ID_KEY), 'Must not contain collections id key');
|
||
idOnlyExcludedExpression = isEmpty(expressionKeys);
|
||
}
|
||
} else {
|
||
// if not specified the add the ID field
|
||
expressionKeys.push(ID_KEY);
|
||
}
|
||
|
||
return collection.map(obj => processObject(obj, expr, expressionKeys, idOnlyExcludedExpression))
|
||
}
|
||
|
||
/**
|
||
* Process the expression value for $project operators
|
||
*
|
||
* @param {Object} obj The object to use as context
|
||
* @param {Object} expr The experssion object of $project operator
|
||
* @param {Array} expressionKeys The key in the 'expr' object
|
||
* @param {Boolean} idOnlyExcludedExpression Boolean value indicating whether only the ID key is excluded
|
||
*/
|
||
function processObject(obj, expr, expressionKeys, idOnlyExcludedExpression) {
|
||
const ID_KEY = idKey();
|
||
|
||
let newObj = {};
|
||
let foundSlice = false;
|
||
let foundExclusion = false;
|
||
let dropKeys = [];
|
||
|
||
if (idOnlyExcludedExpression) {
|
||
dropKeys.push(ID_KEY);
|
||
}
|
||
|
||
expressionKeys.forEach(key => {
|
||
// final computed value of the key
|
||
let value;
|
||
|
||
// expression to associate with key
|
||
let subExpr = expr[key];
|
||
|
||
if (key !== ID_KEY && inArray([0, false], subExpr)) {
|
||
foundExclusion = true;
|
||
}
|
||
|
||
if (key === ID_KEY && isEmpty(subExpr)) {
|
||
// tiny optimization here to skip over id
|
||
value = obj[key];
|
||
} else if (isString(subExpr)) {
|
||
value = computeValue(obj, subExpr, key);
|
||
} else if (inArray([1, true], subExpr)) ; else if (isArray(subExpr)) {
|
||
value = subExpr.map(v => {
|
||
let r = computeValue(obj, v);
|
||
if (isNil(r)) return null
|
||
return r
|
||
});
|
||
} else if (isObject(subExpr)) {
|
||
let subExprKeys = keys(subExpr);
|
||
let operator = subExprKeys.length > 1 ? false : subExprKeys[0];
|
||
|
||
if (inArray(ops(OP_PROJECTION), operator)) {
|
||
const projectionOperators = OPERATORS[OP_PROJECTION];
|
||
|
||
// apply the projection operator on the operator expression for the key
|
||
if (operator === '$slice') {
|
||
// $slice is handled differently for aggregation and projection operations
|
||
if (ensureArray(subExpr[operator]).every(isNumber)) {
|
||
// $slice for projection operation
|
||
value = projectionOperators[operator](obj, subExpr[operator], key);
|
||
foundSlice = true;
|
||
} else {
|
||
// $slice for aggregation operation
|
||
value = computeValue(obj, subExpr, key);
|
||
}
|
||
} else {
|
||
value = projectionOperators[operator](obj, subExpr[operator], key);
|
||
}
|
||
} else {
|
||
// compute the value for the sub expression for the key
|
||
if (has(obj, key)) {
|
||
validateExpression(subExpr);
|
||
let nestedObj = obj[key];
|
||
value = isArray(nestedObj) ?
|
||
nestedObj.map(o => processObject(o, subExpr, subExprKeys, false)) :
|
||
processObject(nestedObj, subExpr, subExprKeys, false);
|
||
} else {
|
||
value = computeValue(obj, subExpr, key);
|
||
}
|
||
}
|
||
} else {
|
||
dropKeys.push(key);
|
||
return
|
||
}
|
||
|
||
// get value with object graph
|
||
let objPathValue = resolveObj(obj, key, {
|
||
preserveMissingValues: true
|
||
});
|
||
|
||
// add the value at the path
|
||
if (objPathValue !== undefined) {
|
||
merge(newObj, objPathValue, {
|
||
flatten: true
|
||
});
|
||
}
|
||
|
||
// if computed add/or remove accordingly
|
||
if (notInArray([0, 1, false, true], subExpr)) {
|
||
if (value === undefined) {
|
||
removeValue(newObj, key);
|
||
} else {
|
||
setValue(newObj, key, value);
|
||
}
|
||
}
|
||
});
|
||
|
||
// filter out all missing values preserved to support correct merging
|
||
filterMissing(newObj);
|
||
|
||
// if projection included $slice operator
|
||
// Also if exclusion fields are found or we want to exclude only the id field
|
||
// include keys that were not explicitly excluded
|
||
if (foundSlice || foundExclusion || idOnlyExcludedExpression) {
|
||
newObj = Object.assign({}, obj, newObj);
|
||
if (dropKeys.length > 0) {
|
||
newObj = cloneDeep(newObj);
|
||
each(dropKeys, k => removeValue(newObj, k));
|
||
}
|
||
}
|
||
|
||
return newObj
|
||
}
|
||
|
||
/**
|
||
* Validate inclusion and exclusion values in expression
|
||
*
|
||
* @param {Object} expr The expression given for the projection
|
||
*/
|
||
function validateExpression(expr) {
|
||
const ID_KEY = idKey();
|
||
let check = [false, false];
|
||
each(expr, (v, k) => {
|
||
if (k === ID_KEY) return
|
||
if (v === 0 || v === false) {
|
||
check[0] = true;
|
||
} else if (v === 1 || v === true) {
|
||
check[1] = true;
|
||
}
|
||
assert(!(check[0] && check[1]), 'Projection cannot have a mix of inclusion and exclusion.');
|
||
});
|
||
}
|
||
|
||
/**
|
||
* Restricts the contents of the documents based on information stored in the documents themselves.
|
||
*
|
||
* https://docs.mongodb.com/manual/reference/operator/aggregation/redact/
|
||
*/
|
||
function $redact (collection, expr, opt) {
|
||
return collection.map(obj => redactObj(cloneDeep(obj), expr))
|
||
}
|
||
|
||
/**
|
||
* Replaces a document with the specified embedded document or new one.
|
||
* The replacement document can be any valid expression that resolves to a document.
|
||
*
|
||
* https://docs.mongodb.com/manual/reference/operator/aggregation/replaceRoot/
|
||
*
|
||
* @param {Array} collection
|
||
* @param {Object} expr
|
||
* @param {Object} opt
|
||
* @return {*}
|
||
*/
|
||
function $replaceRoot (collection, expr, opt) {
|
||
return collection.map(obj => {
|
||
obj = computeValue(obj, expr.newRoot);
|
||
assert(isObject(obj), '$replaceRoot expression must return an object');
|
||
return obj
|
||
})
|
||
}
|
||
|
||
/**
|
||
* Randomly selects the specified number of documents from its input.
|
||
* https://docs.mongodb.com/manual/reference/operator/aggregation/sample/
|
||
*
|
||
* @param {Array} collection
|
||
* @param {Object} expr
|
||
* @param {Object} opt
|
||
* @return {*}
|
||
*/
|
||
function $sample (collection, expr, opt) {
|
||
let size = expr.size;
|
||
assert(isNumber(size), '$sample size must be a positive integer');
|
||
|
||
return collection.transform(xs => {
|
||
let len = xs.length;
|
||
let i = -1;
|
||
return () => {
|
||
if (++i === size) return { done: true }
|
||
let n = Math.floor(Math.random() * len);
|
||
return { value: xs[n], done: false }
|
||
}
|
||
})
|
||
}
|
||
|
||
/**
|
||
* Skips over a specified number of documents from the pipeline and returns the rest.
|
||
*
|
||
* @param collection
|
||
* @param value
|
||
* @param {Object} opt
|
||
* @returns {*}
|
||
*/
|
||
function $skip (collection, value, opt) {
|
||
return collection.drop(value)
|
||
}
|
||
|
||
/**
|
||
* Takes all input documents and returns them in a stream of sorted documents.
|
||
*
|
||
* @param collection
|
||
* @param sortKeys
|
||
* @param {Object} opt
|
||
* @returns {*}
|
||
*/
|
||
function $sort (collection, sortKeys, opt) {
|
||
if (isEmpty(sortKeys) || !isObject(sortKeys)) return collection
|
||
|
||
opt = opt || {};
|
||
let cmp = compare;
|
||
let collationSpec = opt['collation'];
|
||
|
||
// use collation comparator if provided
|
||
if (isObject(collationSpec) && isString(collationSpec.locale)) {
|
||
cmp = collationComparator(collationSpec);
|
||
}
|
||
|
||
return collection.transform(coll => {
|
||
let modifiers = keys(sortKeys);
|
||
|
||
each(modifiers.reverse(), key => {
|
||
let grouped = groupBy(coll, obj => resolve(obj, key));
|
||
let sortedIndex = {};
|
||
|
||
let indexKeys = sortBy(grouped.keys, (k, i) => {
|
||
sortedIndex[k] = i;
|
||
return k
|
||
}, cmp);
|
||
|
||
if (sortKeys[key] === -1) indexKeys.reverse();
|
||
coll = [];
|
||
each(indexKeys, k => into(coll, grouped.groups[sortedIndex[k]]));
|
||
});
|
||
|
||
return coll
|
||
})
|
||
}
|
||
|
||
// MongoDB collation strength to JS localeCompare sensitivity mapping.
|
||
// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/localeCompare
|
||
const COLLATION_STRENGTH = {
|
||
// Only strings that differ in base letters compare as unequal. Examples: a ≠ b, a = á, a = A.
|
||
1: 'base',
|
||
// Only strings that differ in base letters or accents and other diacritic marks compare as unequal.
|
||
// Examples: a ≠ b, a ≠ á, a = A.
|
||
2: 'accent',
|
||
// Strings that differ in base letters, accents and other diacritic marks, or case compare as unequal.
|
||
// Other differences may also be taken into consideration. Examples: a ≠ b, a ≠ á, a ≠ A
|
||
3: 'variant',
|
||
// case - Only strings that differ in base letters or case compare as unequal. Examples: a ≠ b, a = á, a ≠ A.
|
||
};
|
||
|
||
/**
|
||
* Creates a comparator function for the given collation spec. See https://docs.mongodb.com/manual/reference/collation/
|
||
*
|
||
* @param spec {Object} The MongoDB collation spec.
|
||
* {
|
||
* locale: <string>,
|
||
* caseLevel: <boolean>,
|
||
* caseFirst: <string>,
|
||
* strength: <int>,
|
||
* numericOrdering: <boolean>,
|
||
* alternate: <string>,
|
||
* maxVariable: <string>, // unsupported
|
||
* backwards: <boolean> // unsupported
|
||
* }
|
||
*/
|
||
function collationComparator(spec) {
|
||
|
||
let localeOpt = {
|
||
sensitivity: COLLATION_STRENGTH[spec.strength || 3],
|
||
caseFirst: spec.caseFirst === 'off' ? 'false' : (spec.caseFirst || 'false'),
|
||
numeric: spec.numericOrdering || false,
|
||
ignorePunctuation: spec.alternate === 'shifted'
|
||
};
|
||
|
||
// when caseLevel is true for strength 1:base and 2:accent, bump sensitivity to the nearest that supports case comparison
|
||
if ((spec.caseLevel || false) === true) {
|
||
if (localeOpt.sensitivity === 'base') localeOpt.sensitivity = 'case';
|
||
if (localeOpt.sensitivity === 'accent') localeOpt.sensitivity = 'variant';
|
||
}
|
||
|
||
const collator = new Intl.Collator(spec.locale, localeOpt);
|
||
|
||
return (a, b) => {
|
||
// non strings
|
||
if (!isString(a) || !isString(b)) return compare(a, b)
|
||
|
||
// only for strings
|
||
let i = collator.compare(a, b);
|
||
if (i < 0) return -1
|
||
if (i > 0) return 1
|
||
return 0
|
||
}
|
||
}
|
||
|
||
/**
|
||
* Groups incoming documents based on the value of a specified expression,
|
||
* then computes the count of documents in each distinct group.
|
||
*
|
||
* https://docs.mongodb.com/manual/reference/operator/aggregation/sortByCount/
|
||
*
|
||
* @param {Array} collection
|
||
* @param {Object} expr
|
||
* @param {Object} opt
|
||
* @return {*}
|
||
*/
|
||
function $sortByCount (collection, expr, opt) {
|
||
let newExpr = { count: { $sum: 1 } };
|
||
newExpr[idKey()] = expr;
|
||
|
||
return $sort(
|
||
$group(collection, newExpr),
|
||
{ count: -1 },
|
||
opt
|
||
)
|
||
}
|
||
|
||
/**
|
||
* Takes an array of documents and returns them as a stream of documents.
|
||
*
|
||
* @param collection
|
||
* @param expr
|
||
* @param {Object} opt
|
||
* @returns {Array}
|
||
*/
|
||
function $unwind(collection, expr, opt) {
|
||
if (isString(expr)) {
|
||
expr = { path: expr };
|
||
}
|
||
|
||
let field = expr.path.substr(1);
|
||
let includeArrayIndex = expr.includeArrayIndex || false;
|
||
let preserveNullAndEmptyArrays = expr.preserveNullAndEmptyArrays || false;
|
||
|
||
let format = (o, i) => {
|
||
if (includeArrayIndex !== false) o[includeArrayIndex] = i;
|
||
return o
|
||
};
|
||
|
||
let value;
|
||
|
||
return Lazy(() => {
|
||
while (true) {
|
||
// take from lazy sequence if available
|
||
if (Lazy.isIterator(value)) {
|
||
let tmp = value.next();
|
||
if (!tmp.done) return tmp
|
||
}
|
||
|
||
// fetch next object
|
||
let obj = collection.next();
|
||
if (obj.done) return obj
|
||
|
||
// unwrap value
|
||
obj = obj.value;
|
||
|
||
// get the value of the field to unwind
|
||
value = resolve(obj, field);
|
||
|
||
// throw error if value is not an array???
|
||
if (isArray(value)) {
|
||
if (value.length === 0 && preserveNullAndEmptyArrays === true) {
|
||
value = null; // reset unwind value
|
||
let tmp = cloneDeep(obj);
|
||
removeValue(tmp, field);
|
||
return { value: format(tmp, null), done: false }
|
||
} else {
|
||
// construct a lazy sequence for elements per value
|
||
value = Lazy(value).map((item, i) => {
|
||
let tmp = cloneDeep(obj);
|
||
setValue(tmp, field, item);
|
||
return format(tmp, i)
|
||
});
|
||
}
|
||
} else if (!isEmpty(value) || preserveNullAndEmptyArrays === true) {
|
||
let tmp = cloneDeep(obj);
|
||
return { value: format(tmp, null), done: false }
|
||
}
|
||
}
|
||
})
|
||
}
|
||
|
||
/**
|
||
* Pipeline Aggregation Stages. https://docs.mongodb.com/manual/reference/operator/aggregation-
|
||
*/
|
||
|
||
var pipelineOperators = /*#__PURE__*/Object.freeze({
|
||
__proto__: null,
|
||
$addFields: $addFields,
|
||
$set: $set,
|
||
$bucket: $bucket,
|
||
$bucketAuto: $bucketAuto,
|
||
$count: $count,
|
||
$facet: $facet,
|
||
$group: $group,
|
||
$limit: $limit,
|
||
$lookup: $lookup,
|
||
$match: $match,
|
||
$out: $out,
|
||
$project: $project,
|
||
$redact: $redact,
|
||
$replaceRoot: $replaceRoot,
|
||
$sample: $sample,
|
||
$skip: $skip,
|
||
$sort: $sort,
|
||
$sortByCount: $sortByCount,
|
||
$unwind: $unwind
|
||
});
|
||
|
||
/**
|
||
* Projection Operators. https://docs.mongodb.com/manual/reference/operator/projection/
|
||
*/
|
||
|
||
/**
|
||
* Projects the first element in an array that matches the query condition.
|
||
*
|
||
* @param obj
|
||
* @param field
|
||
* @param expr
|
||
*/
|
||
function $ (obj, expr, field) {
|
||
err('$ not implemented');
|
||
}
|
||
|
||
/**
|
||
* Projects only the first element from an array that matches the specified $elemMatch condition.
|
||
*
|
||
* @param obj
|
||
* @param field
|
||
* @param expr
|
||
* @returns {*}
|
||
*/
|
||
function $elemMatch$1 (obj, expr, field) {
|
||
let arr = resolve(obj, field);
|
||
let query = new Query(expr);
|
||
|
||
assert(isArray(arr), '$elemMatch: invalid argument');
|
||
|
||
for (let i = 0; i < arr.length; i++) {
|
||
if (query.test(arr[i])) return [arr[i]]
|
||
}
|
||
return undefined
|
||
}
|
||
|
||
/**
|
||
* Limits the number of elements projected from an array. Supports skip and limit slices.
|
||
*
|
||
* @param obj
|
||
* @param field
|
||
* @param expr
|
||
*/
|
||
function $slice$1 (obj, expr, field) {
|
||
let xs = resolve(obj, field);
|
||
|
||
if (!isArray(xs)) return xs
|
||
|
||
if (isArray(expr)) {
|
||
return slice(xs, expr[0], expr[1])
|
||
} else {
|
||
assert(isNumber(expr), '$slice: invalid arguments for projection');
|
||
return slice(xs, expr)
|
||
}
|
||
}
|
||
|
||
var projectionOperators = /*#__PURE__*/Object.freeze({
|
||
__proto__: null,
|
||
$: $,
|
||
$elemMatch: $elemMatch$1,
|
||
$slice: $slice$1
|
||
});
|
||
|
||
// Query and Projection Operators. https://docs.mongodb.com/manual/reference/operator/query/
|
||
|
||
|
||
function createQueryOperator(pred) {
|
||
return (selector, value) => obj => {
|
||
// value of field must be fully resolved.
|
||
let lhs = resolve(obj, selector, { meta: true });
|
||
lhs = unwrap(lhs.result, lhs.depth);
|
||
return pred(lhs, value)
|
||
}
|
||
}
|
||
|
||
const $all$1 = createQueryOperator($all);
|
||
const $elemMatch$2 = createQueryOperator($elemMatch);
|
||
const $eq$2 = createQueryOperator($eq);
|
||
const $exists$1 = createQueryOperator($exists);
|
||
const $gt$2 = createQueryOperator($gt);
|
||
const $gte$2 = createQueryOperator($gte);
|
||
const $in$2 = createQueryOperator($in$1);
|
||
const $lt$2 = createQueryOperator($lt);
|
||
const $lte$2 = createQueryOperator($lte);
|
||
const $mod$2 = createQueryOperator($mod$1);
|
||
const $ne$2 = createQueryOperator($ne);
|
||
const $nin$2 = createQueryOperator($nin);
|
||
const $regex$1 = createQueryOperator($regex);
|
||
const $size$2 = createQueryOperator($size$1);
|
||
const $type$1 = createQueryOperator($type);
|
||
|
||
/**
|
||
* Joins query clauses with a logical AND returns all documents that match the conditions of both clauses.
|
||
*
|
||
* @param selector
|
||
* @param value
|
||
* @returns {Function}
|
||
*/
|
||
function $and$1 (selector, value) {
|
||
assert(isArray(value), 'Invalid expression: $and expects value to be an Array');
|
||
|
||
let queries = [];
|
||
each(value, (expr) => queries.push(new Query(expr)));
|
||
|
||
return obj => {
|
||
for (let i = 0; i < queries.length; i++) {
|
||
if (!queries[i].test(obj)) {
|
||
return false
|
||
}
|
||
}
|
||
return true
|
||
}
|
||
}
|
||
|
||
/**
|
||
* Joins query clauses with a logical OR returns all documents that match the conditions of either clause.
|
||
*
|
||
* @param selector
|
||
* @param value
|
||
* @returns {Function}
|
||
*/
|
||
function $or$1 (selector, value) {
|
||
assert(isArray(value),'Invalid expression. $or expects value to be an Array');
|
||
|
||
let queries = [];
|
||
each(value, expr => queries.push(new Query(expr)));
|
||
|
||
return obj => {
|
||
for (let i = 0; i < queries.length; i++) {
|
||
if (queries[i].test(obj)) {
|
||
return true
|
||
}
|
||
}
|
||
return false
|
||
}
|
||
}
|
||
|
||
/**
|
||
* Joins query clauses with a logical NOR returns all documents that fail to match both clauses.
|
||
*
|
||
* @param selector
|
||
* @param value
|
||
* @returns {Function}
|
||
*/
|
||
function $nor (selector, value) {
|
||
assert(isArray(value),'Invalid expression. $nor expects value to be an Array');
|
||
let f = $or$1('$or', value);
|
||
return obj => !f(obj)
|
||
}
|
||
|
||
/**
|
||
* Inverts the effect of a query expression and returns documents that do not match the query expression.
|
||
*
|
||
* @param selector
|
||
* @param value
|
||
* @returns {Function}
|
||
*/
|
||
function $not$1 (selector, value) {
|
||
let criteria = {};
|
||
criteria[selector] = normalize(value);
|
||
let query = new Query(criteria);
|
||
return obj => !query.test(obj)
|
||
}
|
||
|
||
/**
|
||
* Matches documents that satisfy a JavaScript expression.
|
||
*
|
||
* @param selector
|
||
* @param value
|
||
* @returns {Function}
|
||
*/
|
||
function $where (selector, value) {
|
||
if (!isFunction(value)) {
|
||
value = new Function('return ' + value + ';');
|
||
}
|
||
return obj => value.call(obj) === true
|
||
}
|
||
|
||
/**
|
||
* Allows the use of aggregation expressions within the query language.
|
||
*
|
||
* @param selector
|
||
* @param value
|
||
* @returns {Function}
|
||
*/
|
||
function $expr (selector, value) {
|
||
return obj => computeValue(obj, value)
|
||
}
|
||
|
||
var queryOperators = /*#__PURE__*/Object.freeze({
|
||
__proto__: null,
|
||
$all: $all$1,
|
||
$elemMatch: $elemMatch$2,
|
||
$eq: $eq$2,
|
||
$exists: $exists$1,
|
||
$gt: $gt$2,
|
||
$gte: $gte$2,
|
||
$in: $in$2,
|
||
$lt: $lt$2,
|
||
$lte: $lte$2,
|
||
$mod: $mod$2,
|
||
$ne: $ne$2,
|
||
$nin: $nin$2,
|
||
$regex: $regex$1,
|
||
$size: $size$2,
|
||
$type: $type$1,
|
||
$and: $and$1,
|
||
$or: $or$1,
|
||
$nor: $nor,
|
||
$not: $not$1,
|
||
$where: $where,
|
||
$expr: $expr
|
||
});
|
||
|
||
// operator definitions
|
||
const OPERATORS = {};
|
||
|
||
OPERATORS[OP_EXPRESSION] = {};
|
||
OPERATORS[OP_GROUP] = {};
|
||
OPERATORS[OP_PIPELINE] = {};
|
||
OPERATORS[OP_PROJECTION] = {};
|
||
OPERATORS[OP_QUERY] = {};
|
||
|
||
const SYSTEM_OPERATORS = [
|
||
[OP_EXPRESSION, expressionOperators],
|
||
[OP_GROUP, groupOperators],
|
||
[OP_PIPELINE, pipelineOperators],
|
||
[OP_PROJECTION, projectionOperators],
|
||
[OP_QUERY, queryOperators]
|
||
];
|
||
|
||
/**
|
||
* Enables the default operators of the system
|
||
*/
|
||
function enableSystemOperators() {
|
||
each(SYSTEM_OPERATORS, arr => {
|
||
let [cls, values] = arr;
|
||
Object.assign(OPERATORS[cls], values);
|
||
});
|
||
}
|
||
|
||
/**
|
||
* Add new operators
|
||
*
|
||
* @param opClass the operator class to extend
|
||
* @param fn a function returning an object of new operators
|
||
*/
|
||
function addOperators (opClass, fn) {
|
||
|
||
const newOperators = fn(_internal());
|
||
|
||
// ensure correct type specified
|
||
assert(has(OPERATORS, opClass), `Invalid operator class ${opClass}`);
|
||
|
||
let operators = OPERATORS[opClass];
|
||
|
||
// check for existing operators
|
||
each(newOperators, (_, op) => {
|
||
assert(/^\$[a-zA-Z0-9_]*$/.test(op), `Invalid operator name ${op}`);
|
||
assert(!has(operators, op), `${op} already exists for '${opClass}' operators`);
|
||
});
|
||
|
||
let wrapped = {};
|
||
|
||
switch (opClass) {
|
||
case OP_QUERY:
|
||
each(newOperators, (fn, op) => {
|
||
fn = fn.bind(newOperators);
|
||
wrapped[op] = (selector, value) => obj => {
|
||
// value of field must be fully resolved.
|
||
let lhs = resolve(obj, selector);
|
||
let result = fn(selector, lhs, value);
|
||
assert(isBoolean(result), `${op} must return a boolean`);
|
||
return result
|
||
};
|
||
});
|
||
break
|
||
case OP_PROJECTION:
|
||
each(newOperators, (fn, op) => {
|
||
fn = fn.bind(newOperators);
|
||
wrapped[op] = (obj, expr, selector) => {
|
||
let lhs = resolve(obj, selector);
|
||
return fn(selector, lhs, expr)
|
||
};
|
||
});
|
||
break
|
||
default:
|
||
each(newOperators, (fn, op) => {
|
||
wrapped[op] = (...args) => fn.apply(newOperators, args);
|
||
});
|
||
}
|
||
|
||
// toss the operator salad :)
|
||
Object.assign(OPERATORS[opClass], wrapped);
|
||
}
|
||
|
||
/**
|
||
* Mixin for Collection types that provide a method `toJSON() -> Array[Object]`
|
||
*/
|
||
const CollectionMixin = {
|
||
|
||
/**
|
||
* Runs a query and returns a cursor to the result
|
||
* @param criteria
|
||
* @param projection
|
||
* @returns {Cursor}
|
||
*/
|
||
query (criteria, projection) {
|
||
return new Query(criteria).find(this.toJSON(), projection)
|
||
},
|
||
|
||
/**
|
||
* Runs the given aggregation operators on this collection
|
||
* @params pipeline
|
||
* @returns {Array}
|
||
*/
|
||
aggregate (pipeline) {
|
||
return new Aggregator(pipeline).run(this.toJSON())
|
||
}
|
||
};
|
||
|
||
enableSystemOperators();
|
||
|
||
const VERSION = '2.5.3';
|
||
|
||
// mingo!
|
||
var index = {
|
||
_internal,
|
||
Aggregator,
|
||
CollectionMixin,
|
||
Cursor,
|
||
Lazy,
|
||
OP_EXPRESSION,
|
||
OP_GROUP,
|
||
OP_PIPELINE,
|
||
OP_PROJECTION,
|
||
OP_QUERY,
|
||
Query,
|
||
VERSION,
|
||
addOperators,
|
||
aggregate,
|
||
find,
|
||
remove,
|
||
setup
|
||
};
|
||
|
||
export default index;
|