Styjun

I have a timing or scope problem on this function call.. or no idea what.

 AjaxHandlerByClass('url', clientName: this.clientName, function (response) this code gets never called)
 AjaxHandlerByClass('url', clientName: this.clientName, function (response) This code gets called 2 times)

From this Function

function AjaxHandlerByClass(className, postData, callback, callbackFail) 

 var timestamp = new Date().getTime();

 var me = this;
 me.backHandler = function (data) data.debug) 
 if (data.debug)
 var debug = data.debug;
 else if (data.responseJSON && data.responseJSON.debug)
 var debug = data.responseJSON.debug;
 if (window.console) 
 for (var key in debug) 
 if (debug.hasOwnProperty(key)) 
 // console.log(debug[key]);
 
 
 

 
 if (me.mode = 'callback') 
 callback(data); //<--- this is the bug location
 else 
 callbackFail(data);
 
 ;

 this.ok = function (data) 
 me.mode = 'callback';
 me.backHandler(data)
 

 this.notOk = function (data) 
 me.mode = 'callbackFail';
 me.backHandler(data)
 

 $.ajax(
 
 contentType: "application/json; charset=utf-8",
 url: className + '?ts=' + timestamp + '&sid=' + sid,
 type: 'post',
 data: JSON.stringify(postData),
 dataType: 'json',
 cache: false,
 success: me.ok,
 error: me.notOk
 
 );

The first callback Function never gets executed, while the second one does get executed but 2 times.

The bug happens on the if (me.mode = 'callback') part of the code.
I already tried other options to make the callback function stuck right.

The first attempt was to store the callback function in the Function scope itself.
with assigning it to this.callback and then trying to access it via me.scope
which did not work. then I tried to access the variables directly.. and it is not helping either...

 this.callback = callback;
 this.callbackFail = callbackFail;

 var me = this;
 me.backHandler = function (data) ;

I'm on my wit's end.

First of, callBackFail is never defined in your code.

function AjaxHandlerByClass(className, postData, callback, callbackFail)

You pass in three parameters: className, postData and callback.

AjaxHandlerByClass('url', clientName: this.clientName, function (response) this code gets never called)

Second, this line should be me.mode === 'callback', not me.mode = 'callback'

if (me.mode === 'callback') 
 callback(data);
 else 
 callbackFail(data);

You've named your function AjaxHandlerByClass, I assume you want to use it as a class. You've declared it as function. Regular functions are executed when they are invoked(called) causing the second call to AjaxHandlerByClass() to render twice. To solve your problem you could either create a new instance of your AjaxHandlerByClass using the new keyword.

const firstRequst = new AjaxHandlerByClass('url', clientName: "https://swapi.co/api/people/", successCallback, failCallback);

const secondRequst = new AjaxHandlerByClass('url', clientName: "https://swapi.co/api/planets/", successCallback, failCallback);

Or if you want to wait for the first request to finish before calling the second request you could implement Promise. More on Promise here.

I created a js-fiddle here with some modifications(swapped api and renamed some varaibles just for testing purpose.). One of the ajax-request is successful and the other fails. The result is visible in the developer-console. Note this fiddle is not perfectly written, its just some dummy code for demo purpose.