1 line
18 KiB
Plaintext
1 line
18 KiB
Plaintext
|
{"version":3,"file":"awareness.cjs","sources":["../awareness.js"],"sourcesContent":["/**\n * @module awareness-protocol\n */\n\nimport * as encoding from 'lib0/encoding'\nimport * as decoding from 'lib0/decoding'\nimport * as time from 'lib0/time'\nimport * as math from 'lib0/math'\nimport { Observable } from 'lib0/observable'\nimport * as f from 'lib0/function'\nimport * as Y from 'yjs' // eslint-disable-line\n\nexport const outdatedTimeout = 30000\n\n/**\n * @typedef {Object} MetaClientState\n * @property {number} MetaClientState.clock\n * @property {number} MetaClientState.lastUpdated unix timestamp\n */\n\n/**\n * The Awareness class implements a simple shared state protocol that can be used for non-persistent data like awareness information\n * (cursor, username, status, ..). Each client can update its own local state and listen to state changes of\n * remote clients. Every client may set a state of a remote peer to `null` to mark the client as offline.\n *\n * Each client is identified by a unique client id (something we borrow from `doc.clientID`). A client can override\n * its own state by propagating a message with an increasing timestamp (`clock`). If such a message is received, it is\n * applied if the known state of that client is older than the new state (`clock < newClock`). If a client thinks that\n * a remote client is offline, it may propagate a message with\n * `{ clock: currentClientClock, state: null, client: remoteClient }`. If such a\n * message is received, and the known clock of that client equals the received clock, it will override the state with `null`.\n *\n * Before a client disconnects, it should propagate a `null` state with an updated clock.\n *\n * Awareness states must be updated every 30 seconds. Otherwise the Awareness instance will delete the client state.\n *\n * @extends {Observable<string>}\n */\nexport class Awareness extends Observable {\n /**\n * @param {Y.Doc} doc\n */\n constructor (doc) {\n super()\n this.doc = doc\n /**\n * @type {number}\n */\n this.clientID = doc.clientID\n /**\n * Maps from client id to client state\n * @type {Map<number, Object<string, any>>}\n */\n this.states = new Map()\n /**\n * @type {Map<number, MetaClientState>}\n */\n this.meta = new Map()\n this._checkInterval = /** @type {any} */ (setInterval(() => {\n const now = time.getUnixTime()\n if (this.getLocalState() !== null && (outdatedTimeout / 2 <= now - /** @type {{lastUpdated:number}} */ (this.meta.get(this.clientID)).lastUpdated)) {\n // renew local clock\n this.setLocalState(this.getLocalState())\n }\n /**\n * @type {Array<number>}\n */\n const remove = []\n this.meta.forEach((meta, clientid) => {\n if (clientid !== this.clientID && outdatedTimeout <= now - meta.lastUpdated && this.states.has(clientid)) {\n remove.push(clientid)\n }\n })\n if (remove.length > 0) {\n removeAwarenessStates(this, remove, 'timeout')\n }\n }, math.floor(outdatedTimeout / 10)))\n doc.on('destroy', () => {\n this.destroy()\n })\n this.setLocalState({})\n }\n\n destroy () {\n this.emit('destroy', [this])\n this.setLocalState(null)\n super.destroy()\n clearInterval(this._checkInterval)\n }\n\n /**\n * @return {Object<string,any>|null}\n */\n getLocalState () {\n return this.states.get(this.clientID) || null\n }\n\n /**\n * @param {Object<string,any>|null} state\n */\n setLocalState (state) {\n const clientID = this.clientID\n const currLocalMeta = this.meta.get(clientID)\n const clock = currLocalMeta === undefined ? 0 : currLocalMeta.clock + 1\n const prevState = this.states.get(clientID)\n if (state === null) {\n this.states.delete(clientID)\n } else {\n this.states.set(clientID, state)\n }\n this.meta.set(clientID, {\n clock,\n lastUpdated: time.getUnixTime()\n })\n const added = []\n const updated = []\n const filteredUpdated = []\n const removed = []\
|