| var Stream = require('stream').Stream; |
| var util = require('util'); |
| |
| module.exports = DelayedStream; |
| function DelayedStream() { |
| this.source = null; |
| this.dataSize = 0; |
| this.maxDataSize = 1024 * 1024; |
| this.pauseStream = true; |
| |
| this._maxDataSizeExceeded = false; |
| this._released = false; |
| this._bufferedEvents = []; |
| } |
| util.inherits(DelayedStream, Stream); |
| |
| DelayedStream.create = function(source, options) { |
| var delayedStream = new this(); |
| |
| options = options || {}; |
| for (var option in options) { |
| delayedStream[option] = options[option]; |
| } |
| |
| delayedStream.source = source; |
| |
| var realEmit = source.emit; |
| source.emit = function() { |
| delayedStream._handleEmit(arguments); |
| return realEmit.apply(source, arguments); |
| }; |
| |
| source.on('error', function() {}); |
| if (delayedStream.pauseStream) { |
| source.pause(); |
| } |
| |
| return delayedStream; |
| }; |
| |
| Object.defineProperty(DelayedStream.prototype, 'readable', { |
| configurable: true, |
| enumerable: true, |
| get: function() { |
| return this.source.readable; |
| } |
| }); |
| |
| DelayedStream.prototype.setEncoding = function() { |
| return this.source.setEncoding.apply(this.source, arguments); |
| }; |
| |
| DelayedStream.prototype.resume = function() { |
| if (!this._released) { |
| this.release(); |
| } |
| |
| this.source.resume(); |
| }; |
| |
| DelayedStream.prototype.pause = function() { |
| this.source.pause(); |
| }; |
| |
| DelayedStream.prototype.release = function() { |
| this._released = true; |
| |
| this._bufferedEvents.forEach(function(args) { |
| this.emit.apply(this, args); |
| }.bind(this)); |
| this._bufferedEvents = []; |
| }; |
| |
| DelayedStream.prototype.pipe = function() { |
| var r = Stream.prototype.pipe.apply(this, arguments); |
| this.resume(); |
| return r; |
| }; |
| |
| DelayedStream.prototype._handleEmit = function(args) { |
| if (this._released) { |
| this.emit.apply(this, args); |
| return; |
| } |
| |
| if (args[0] === 'data') { |
| this.dataSize += args[1].length; |
| this._checkIfMaxDataSizeExceeded(); |
| } |
| |
| this._bufferedEvents.push(args); |
| }; |
| |
| DelayedStream.prototype._checkIfMaxDataSizeExceeded = function() { |
| if (this._maxDataSizeExceeded) { |
| return; |
| } |
| |
| if (this.dataSize <= this.maxDataSize) { |
| return; |
| } |
| |
| this._maxDataSizeExceeded = true; |
| var message = |
| 'DelayedStream#maxDataSize of ' + this.maxDataSize + ' bytes exceeded.' |
| this.emit('error', new Error(message)); |
| }; |