92 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
			
		
		
	
	
			92 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
var streamify = require('./streamify.js')
 | 
						||
  , defer     = require('./defer.js')
 | 
						||
  ;
 | 
						||
 | 
						||
// API
 | 
						||
module.exports = ReadableAsyncKit;
 | 
						||
 | 
						||
/**
 | 
						||
 * Base constructor for all streams
 | 
						||
 * used to hold properties/methods
 | 
						||
 */
 | 
						||
function ReadableAsyncKit()
 | 
						||
{
 | 
						||
  ReadableAsyncKit.super_.apply(this, arguments);
 | 
						||
 | 
						||
  // list of active jobs
 | 
						||
  this.jobs = {};
 | 
						||
 | 
						||
  // add stream methods
 | 
						||
  this.destroy = destroy;
 | 
						||
  this._start  = _start;
 | 
						||
  this._read   = _read;
 | 
						||
}
 | 
						||
 | 
						||
/**
 | 
						||
 * Destroys readable stream,
 | 
						||
 * by aborting outstanding jobs
 | 
						||
 *
 | 
						||
 * @returns {void}
 | 
						||
 */
 | 
						||
function destroy()
 | 
						||
{
 | 
						||
  if (this.destroyed)
 | 
						||
  {
 | 
						||
    return;
 | 
						||
  }
 | 
						||
 | 
						||
  this.destroyed = true;
 | 
						||
 | 
						||
  if (typeof this.terminator == 'function')
 | 
						||
  {
 | 
						||
    this.terminator();
 | 
						||
  }
 | 
						||
}
 | 
						||
 | 
						||
/**
 | 
						||
 * Starts provided jobs in async manner
 | 
						||
 *
 | 
						||
 * @private
 | 
						||
 */
 | 
						||
function _start()
 | 
						||
{
 | 
						||
  // first argument – runner function
 | 
						||
  var runner = arguments[0]
 | 
						||
    // take away first argument
 | 
						||
    , args   = Array.prototype.slice.call(arguments, 1)
 | 
						||
      // second argument - input data
 | 
						||
    , input  = args[0]
 | 
						||
      // last argument - result callback
 | 
						||
    , endCb  = streamify.callback.call(this, args[args.length - 1])
 | 
						||
    ;
 | 
						||
 | 
						||
  args[args.length - 1] = endCb;
 | 
						||
  // third argument - iterator
 | 
						||
  args[1] = streamify.iterator.call(this, args[1]);
 | 
						||
 | 
						||
  // allow time for proper setup
 | 
						||
  defer(function()
 | 
						||
  {
 | 
						||
    if (!this.destroyed)
 | 
						||
    {
 | 
						||
      this.terminator = runner.apply(null, args);
 | 
						||
    }
 | 
						||
    else
 | 
						||
    {
 | 
						||
      endCb(null, Array.isArray(input) ? [] : {});
 | 
						||
    }
 | 
						||
  }.bind(this));
 | 
						||
}
 | 
						||
 | 
						||
 | 
						||
/**
 | 
						||
 * Implement _read to comply with Readable streams
 | 
						||
 * Doesn't really make sense for flowing object mode
 | 
						||
 *
 | 
						||
 * @private
 | 
						||
 */
 | 
						||
function _read()
 | 
						||
{
 | 
						||
 | 
						||
}
 |