@emartech/faye-redis-sharded/vendor/faye/javascript/transport/cors.js

Redis backend engine for Faye with support for sharding

Faye.Transport.CORS = Faye.extend(Faye.Class(Faye.Transport, {
  encode: function(envelopes) {
    var messages = Faye.map(envelopes, function(e) { return e.message });
    return 'message=' + encodeURIComponent(Faye.toJSON(messages));
  },

  request: function(envelopes) {
    var xhrClass = Faye.ENV.XDomainRequest ? XDomainRequest : XMLHttpRequest,
        xhr      = new xhrClass(),
        headers  = this._client.headers,
        self     = this,
        key;

    xhr.open('POST', Faye.URI.stringify(this.endpoint), true);

    if (xhr.setRequestHeader) {
      xhr.setRequestHeader('Pragma', 'no-cache');
      for (key in headers) {
        if (!headers.hasOwnProperty(key)) continue;
        xhr.setRequestHeader(key, headers[key]);
      }
    }

    var cleanUp = function() {
      if (!xhr) return false;
      xhr.onload = xhr.onerror = xhr.ontimeout = xhr.onprogress = null;
      xhr = null;
    };

    xhr.onload = function() {
      var parsedMessage = null;
      try {
        parsedMessage = JSON.parse(xhr.responseText);
      } catch (e) {}

      cleanUp();

      if (parsedMessage)
        self.receive(envelopes, parsedMessage);
      else
        self.handleError(envelopes);
    };

    xhr.onerror = xhr.ontimeout = function() {
      cleanUp();
      self.handleError(envelopes);
    };

    xhr.onprogress = function() {};
    xhr.send(this.encode(envelopes));
    return xhr;
  }
}), {
  isUsable: function(client, endpoint, callback, context) {
    if (Faye.URI.isSameOrigin(endpoint))
      return callback.call(context, false);

    if (Faye.ENV.XDomainRequest)
      return callback.call(context, endpoint.protocol === Faye.ENV.location.protocol);

    if (Faye.ENV.XMLHttpRequest) {
      var xhr = new Faye.ENV.XMLHttpRequest();
      return callback.call(context, xhr.withCredentials !== undefined);
    }
    return callback.call(context, false);
  }
});

Faye.Transport.register('cross-origin-long-polling', Faye.Transport.CORS);