Tracker Mixin for React

TrackerMixin.js

/**
 * React Mixin for binding reactive data sources and DDP subscriptions
 * to the state of a component using Tracker
 *
 * Components using this mixin should implement getTrackerState and/or
 * ddpSubscriptions
 */
TrackerMixin = {

  getInitialState: function() {
    if ( self.ddpSubscriptions ) {
      return {
        subsReady: false
      };
    }
    return {};
    
  },

  componentWillMount: function() {
    var self = this;
    // self._trackerDep = new Tracker.Dependency();

    if ( Meteor.isClient ) {
      Tracker.autorun( function(computation) {
        self._trackerComputation = computation;
        // self._trackerDep.depend();

        if ( self.ddpSubscriptions ) {
          // By setting up subscriptions in a Tracker.autorun they will
          // automatically be canceled when the computation stops
          // console.log("TrackerMixin rerunning DDP subscriptions");
          var handles = self.ddpSubscriptions();
          var ready;
          if (_.isArray(handles)) {
            // if it's an array of handles, wait on all of them
            // to be ready
            ready = _.reduce(
              handles, 
              function(result, handle) {
                return result && handle.ready();
              }, 
              true
            );
          } else {
            ready = handles.ready();
          }
          self.setState({ subsReady: ready });
        }

        if ( self.getTrackerState ) {
          self.setState( self.getTrackerState() );
        }
      });
    } else { // we're on the server
      if ( self.getTrackerState ) {
        self.setState( self.getTrackerState() );
      }
    }
  },

  // This is here in case getTrackerState relies on any prop values
  // If you're doing reactivity based on props, you're doing it wrong
  // componentWillReceiveProps: function(nextProps) {
  //   if (this._trackerDep) {
  //     var oldProps = this.props;
  //     this.props = nextProps; // setup props for the autorun
  //     this._trackerDep.changed(); // trigger the autorun
  //     Tracker.flush();  // make sure the autorun goes
  //                       // XX this was giving a bug when no props were being used
  //                       // "can't call tracker.flush while flushing"
  //     this.props = oldProps;  // setup props back to what they were
  //                             // React will handle actually setting them
  //   }
  // },

  componentWillUnmount: function() {
    if ( this._trackerComputation ) {
      this._trackerComputation.stop();
      this._trackerComputation = null;
    }
  }

};