github.com/insionng/yougam@v0.0.0-20170714101924-2bc18d833463/themes/wind/static/libs/sockjs-client-1.1.0/lib/transport/sender/xdr.js (about)

     1  'use strict';
     2  
     3  var EventEmitter = require('events').EventEmitter
     4    , inherits = require('inherits')
     5    , eventUtils = require('../../utils/event')
     6    , browser = require('../../utils/browser')
     7    , urlUtils = require('../../utils/url')
     8    ;
     9  
    10  var debug = function() {};
    11  if (process.env.NODE_ENV !== 'production') {
    12    debug = require('debug')('sockjs-client:sender:xdr');
    13  }
    14  
    15  // References:
    16  //   http://ajaxian.com/archives/100-line-ajax-wrapper
    17  //   http://msdn.microsoft.com/en-us/library/cc288060(v=VS.85).aspx
    18  
    19  function XDRObject(method, url, payload) {
    20    debug(method, url);
    21    var self = this;
    22    EventEmitter.call(this);
    23  
    24    setTimeout(function() {
    25      self._start(method, url, payload);
    26    }, 0);
    27  }
    28  
    29  inherits(XDRObject, EventEmitter);
    30  
    31  XDRObject.prototype._start = function(method, url, payload) {
    32    debug('_start');
    33    var self = this;
    34    var xdr = new global.XDomainRequest();
    35    // IE caches even POSTs
    36    url = urlUtils.addQuery(url, 't=' + (+new Date()));
    37  
    38    xdr.onerror = function() {
    39      debug('onerror');
    40      self._error();
    41    };
    42    xdr.ontimeout = function() {
    43      debug('ontimeout');
    44      self._error();
    45    };
    46    xdr.onprogress = function() {
    47      debug('progress', xdr.responseText);
    48      self.emit('chunk', 200, xdr.responseText);
    49    };
    50    xdr.onload = function() {
    51      debug('load');
    52      self.emit('finish', 200, xdr.responseText);
    53      self._cleanup(false);
    54    };
    55    this.xdr = xdr;
    56    this.unloadRef = eventUtils.unloadAdd(function() {
    57      self._cleanup(true);
    58    });
    59    try {
    60      // Fails with AccessDenied if port number is bogus
    61      this.xdr.open(method, url);
    62      if (this.timeout) {
    63        this.xdr.timeout = this.timeout;
    64      }
    65      this.xdr.send(payload);
    66    } catch (x) {
    67      this._error();
    68    }
    69  };
    70  
    71  XDRObject.prototype._error = function() {
    72    this.emit('finish', 0, '');
    73    this._cleanup(false);
    74  };
    75  
    76  XDRObject.prototype._cleanup = function(abort) {
    77    debug('cleanup', abort);
    78    if (!this.xdr) {
    79      return;
    80    }
    81    this.removeAllListeners();
    82    eventUtils.unloadDel(this.unloadRef);
    83  
    84    this.xdr.ontimeout = this.xdr.onerror = this.xdr.onprogress = this.xdr.onload = null;
    85    if (abort) {
    86      try {
    87        this.xdr.abort();
    88      } catch (x) {
    89        // intentionally empty
    90      }
    91    }
    92    this.unloadRef = this.xdr = null;
    93  };
    94  
    95  XDRObject.prototype.close = function() {
    96    debug('close');
    97    this._cleanup(true);
    98  };
    99  
   100  // IE 8/9 if the request target uses the same scheme - #79
   101  XDRObject.enabled = !!(global.XDomainRequest && browser.hasDomain());
   102  
   103  module.exports = XDRObject;