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

Redis backend engine for Faye with support for sharding

Faye.Transport.EventSource = Faye.extend(Faye.Class(Faye.Transport, {
  initialize: function(client, endpoint) {
    Faye.Transport.prototype.initialize.call(this, client, endpoint);
    if (!Faye.ENV.EventSource) return this.setDeferredStatus('failed');

    this._xhr = new Faye.Transport.XHR(client, endpoint);

    endpoint = Faye.copyObject(endpoint);
    endpoint.pathname += '/' + client._clientId;

    var socket = new EventSource(Faye.URI.stringify(endpoint)),
        self   = this;

    socket.onopen = function() {
      self._everConnected = true;
      self.setDeferredStatus('succeeded');
    };

    socket.onerror = function() {
      if (self._everConnected) {
        self._client.messageError([]);
      } else {
        self.setDeferredStatus('failed');
        socket.close();
      }
    };

    socket.onmessage = function(event) {
      self.receive([], JSON.parse(event.data));
    };

    this._socket = socket;
  },

  close: function() {
    if (!this._socket) return;
    this._socket.onopen = this._socket.onerror = this._socket.onmessage = null;
    this._socket.close();
    delete this._socket;
  },

  isUsable: function(callback, context) {
    this.callback(function() { callback.call(context, true) });
    this.errback(function() { callback.call(context, false) });
  },

  encode: function(envelopes) {
    return this._xhr.encode(envelopes);
  },

  request: function(envelopes) {
    this._xhr.request(envelopes);
  }

}), {
  isUsable: function(client, endpoint, callback, context) {
    var id = client._clientId;
    if (!id) return callback.call(context, false);

    Faye.Transport.XHR.isUsable(client, endpoint, function(usable) {
      if (!usable) return callback.call(context, false);
      this.create(client, endpoint).isUsable(callback, context);
    }, this);
  },

  create: function(client, endpoint) {
    var sockets = client.transports.eventsource = client.transports.eventsource || {},
        id      = client._clientId;

    endpoint = Faye.copyObject(endpoint);
    endpoint.pathname += '/' + (id || '');
    var url = Faye.URI.stringify(endpoint);

    sockets[url] = sockets[url] || new this(client, endpoint);
    return sockets[url];
  }
});

Faye.extend(Faye.Transport.EventSource.prototype, Faye.Deferrable);
Faye.Transport.register('eventsource', Faye.Transport.EventSource);