lifecycleMixin.js

//   Copyright 2014-2015 François de Campredon
//
//   Licensed under the Apache License, Version 2.0 (the "License");
//   you may not use this file except in compliance with the License.
//   You may obtain a copy of the License at
//
//       http://www.apache.org/licenses/LICENSE-2.0
//
//   Unless required by applicable law or agreed to in writing, software
//   distributed under the License is distributed on an "AS IS" BASIS,
//   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
//   See the License for the specific language governing permissions and
//   limitations under the License.

'use strict';

var Rx = require('rx');

/**
 * A Mixin that exposes lifecycle as RxJS Observables
 */
var LifecycleMixin = {
  getInitialState: function () {
    this.__lifecycle = {
      componentWillMount: new Rx.Subject(),
      componentDidMount: new Rx.Subject(),
      componentWillReceiveProps: new Rx.Subject(),
      componentWillUpdate: new Rx.Subject(),
      componentDidUpdate: new Rx.Subject(),
      componentWillUnmount: new Rx.Subject()
    };
    
    this.lifecycle = Object.keys(this.__lifecycle).reduce(function (lifecycle, prop) {
      if (prop !== 'componentWillUnmount') {
        lifecycle[prop] = this.__lifecycle[prop].takeUntil(this.__lifecycle.componentWillUnmount);
      } else {
        lifecycle[prop] = this.__lifecycle[prop].take(1);
      }
      return lifecycle;
    }.bind(this), {});
    
    return null;
  },
  
  componentWillMount: function () {
    this.__lifecycle.componentWillMount.onNext();
  },
  componentDidMount: function () {
    this.__lifecycle.componentDidMount.onNext();
  },
  componentWillReceiveProps: function (nextProps) {
    this.__lifecycle.componentWillReceiveProps.onNext(nextProps);
  },
  componentWillUpdate: function (nextProps, nextState) {
    this.__lifecycle.componentWillUpdate.onNext({ nextProps: nextProps, nextState: nextState });
  },
  componentDidUpdate: function (prevProps, prevState) {
    this.__lifecycle.componentDidUpdate.onNext({ prevProps: prevProps, prevState: prevState });
  },
  componentWillUnmount: function () {
    this.__lifecycle.componentWillUnmount.onNext();
  }
};

module.exports = LifecycleMixin;