dynatrace-cordova-outsystems-plugin/node_modules/delayed-stream/lib/delayed_stream.js

This plugin gives you the ability to use the Dynatrace instrumentation in your hybrid application (Cordova, Ionic, ..). It uses the Mobile Agent, the JavaScript Agent and the Javascript Bridge. The Mobile Agent will give you all device specific values con

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));
};