RedisEvent.js

/**
 * Creates a event listener for redis keyspace notifications
 * @param client {Redis} - An instance of node-redis client to connect with
 * @param event {String} - The type of keyspace event
 * @param keyPattern {RegExp} - RegExp pattern to match for key names
 * @constructor
 */
var RedisEvent = function(client, event, keyPattern){
  var _this = this;

  this.redis = client;
  this.redis.client('setname', 'event-listener');

  this.keyPattern = keyPattern;

  this.handler = null;

  this.redis.subscribe('__keyevent@0__:' + event);
  this.redis.on('message', function(event, key){
    var match = _this.keyPattern.exec(key);
    if(match != null){
      if(_this.handler != null){
        _this.handler(match);
      } else {
        throw 'NoHandlerException';
      }
    }
  });
};

RedisEvent.prototype = {
};

/**
 * Sets the handler for the event
 * @param {Function} handler - The function that is called when the event occurs.
 */
RedisEvent.prototype.defineHandler = function(handler){
  this.handler = handler;
};

module.exports = RedisEvent;