var once = require('once') var eos = require('end-of-stream') var fs try { fs = require('fs') // we only need fs to get the ReadStream and WriteStream prototypes } catch (e) {} var noop = function () {} var ancient = /^v?\.0/.test(process.version) var isFn = function (fn) { return typeof fn === 'function' } var isFS = function (stream) { if (!ancient) return false // newer node version do not need to care about fs is a special way if (!fs) return false // browser return (stream instanceof (fs.ReadStream || noop) || stream instanceof (fs.WriteStream || noop)) && isFn(stream.close) } var isRequest = function (stream) { return stream.setHeader && isFn(stream.abort) } var destroyer = function (stream, reading, writing, callback) { callback = once(callback) var closed = false stream.on('close', function () { closed = true }) eos(stream, {readable: reading, writable: writing}, function (err) { if (err) return callback(err) closed = true callback() }) var destroyed = false return function (err) { if (closed) return if (destroyed) return destroyed = true if (isFS(stream)) return stream.close(noop) // use close for fs streams to avoid fd leaks if (isRequest(stream)) return stream.abort() // request.destroy just do .end - .abort is what we want if (isFn(stream.destroy)) return stream.destroy() callback(err || new Error('stream was destroyed')) } } var call = function (fn) { fn() } var pipe = function (from, to) { return from.pipe(to) } var pump = function () { var streams = Array.prototype.slice.call(arguments) var callback = isFn(streams[streams.length - 1] || noop) && streams.pop() || noop if (Array.isArray(streams[0])) streams = streams[0] if (streams.length < 2) throw new Error('pump requires two streams per minimum') var error var destroys = streams.map(function (stream, i) { var reading = i < streams.length - 1 var writing = i > 0 return destroyer(stream, reading, writing, function (err) { if (!error) error = err if (err) destroys.forEach(call) if (reading) return destroys.forEach(call) callback(error) }) }) return streams.reduce(pipe) } module.exports = pump