Extjs Poller utility

Poller.js

Ext.define('Empty.common.Poller', {
  singleton: true,
  alternateClassName: ['Poller'],


  /**
   * Utility to poll an endpoint provided with the required parameters
   * Mandatory parameters are : params.pollInterval, params.pollTimeout, params.success
   * @params {Object} params
   * 
   */
  poll: function (params) {
    var url = params.url,
      pollInterval = params.pollInterval,
      pollTimeout = params.pollTimeout,
      success = params.success,
      failure = params.failure,
      endTime = Number(new Date()) + pollTimeout*1000;

    if(!pollInterval || !pollTimeout || !success) {
      console.log('Mandatory parameters are missing for starting polling. Please provide [pollInterval, pollTimeout, success] ');
      return;
    }
    if(success && !Ext.isFunction(success)) {
      console.warn('success ');
      success = function () {};
    }
    if(failure && !Ext.isFunction(failure)) {
      failure = function () {};
    }

    (function p() {
      Ext.Ajax.request({
        url: url + '?_dc=' + (new Date()).getTime(),
        failure: function (response, operation) {
          console.log("Lookup Response failure callback");
          console.dir(response);
          console.dir(operation);
          failure();
        },
        success: function (response, operation) {
          if (response.status === 204) {
            if (Number(new Date()) > endTime) {
              console.log('Client timeout occurred!! Stopping polling routine ....');
              failure(new Error('Failed due to client timeout..'), true);
            } else {
              // keep polling until data is received or timeout occurs
              console.log('Data not received yet. Scheduling next poll after ' + pollInterval + ' seconds...');
              setTimeout(p, pollInterval*1000);
            }
          } else {
            var data = response.responseText ? Ext.JSON.decode(response.responseText) : null;
            if (data) {
              success(data);
            } else {
              failure(new Error('HTTP OK  returned from server but no data received.. Stopping polling.'), false);
            }
          }
        }
      });
    })();
  }
});