CODEWITHSUNDEEP
javascriptnode.jsasynchronousasync.js
Sumeet Kumar Yadav
Sumeet Kumar Yadav

Reputation: 12945

Node.js async parallel "TypeError: task is not a function"

I am using the async module to execute parallel tasks. Basically, I have two different files, dashboard.js and Run.js.

Dashboard.js

module.exports = {

    func1 : function(){
        console.log(“Funtion one”);

    },
    func2 : function(){
        console.log(“Funtion two”);
    }

}

Run.js

    var dashboard = require(‘dashboard.js’);

    var async = require('async');

    async.parallel([dashboard.func1, dashboard.func2],function(err){
        if(err)throws err;
        console.log(“ All function executed”);
   });

I was expecting func1 and func2 to execute in parallel, but it is throwing the below error.

TypeError: task is not a function
    at C:\Users\..\java\realtime-preview\node_modules\async\lib\async.js:718:13
    at async.forEachOf.async.eachOf (C:\Users\..\java\realtime-preview\node_modules\async\lib\async.js:233:13)
    at _parallel (C:\Users\\java\realtime-preview\node_modules\async\lib\async.js:717:9)

why can I not use dashboard.func1, dashboard.func2 even if dashboard.func1 is a function?

Upvotes: 5

Views: 5130

Answers (2)

Sanjay Tiwari
Sanjay Tiwari

Reputation: 133

Please make sure the API path you are using should not have any return .. I have resolve this issue after calling API like this ... Please not i was facing this while working in local


fetchLearnMoreProxy: (isoCode, langCode) =>
    `http://localhost:3001/api?url=${hostName}/api/abc/cde?country=${isoCode}&language=${langCode}`,

Please let me know if any question.

Upvotes: 0

Michael Seltene
Michael Seltene

Reputation: 591

For the async property, I would use the callback feature. This feature also benefits non-blocking calls.

With your code, you could try

File Dashboard.js

module.exports = {
   func1 : function(callback){
       var value = “Function one”;

       // If value happens to be empty, then undefined is called back
       callback(undefined|| value);
   },
   func2 : function(callback){
       var value = “Function two”;

       // If value happens to be empty, then undefined is calledback
       callback(undefined|| value);
   }
}

File Run.js

var dashboard = require(‘dashboard.js’);

   //func1
   dashboard.func1(function(callback){

     // If callback then do the following
     if(callback){
         console.log(callback);

     // If no data on callback then do the following
     }else{
         console.error('Error: ' + callback);
     }
   });

   //func2
   dashboard.func2(function(callback){

     // If callback then do the following
     if(callback){
         console.log(callback);

     // If no data on callback then do the following
     }else{
         console.error('Error: ' + callback);
     }
   });
});

There is also a question similar to yours: Best way to execute parallel processing in Node.js

In addition, a specific answer for the error is in: TypeError: task is not a function in async js parrallel

Upvotes: 2

Related Questions