node js value return

I am a beginner to node js. Trying to call a API and result should pass to another function. Because of callback functionality second function [Task2()]is executing soon after calling the first function[Task1()], How can I handle this asynchronous behavior of node js code. I have googled for yield , but not succeeded. I have provided below sample code for your reference. Please provide your comments/suggestions.

var result='';

function Task1(){  //2 --> Executing task1  

Task_Id='';
var options = {
  uri: 'http://url/post', //url to call
  method: 'POST',
  auth: {
        'user': 'user1',
        'pass': 'paswd1'
    },
  json: {
       "key":"value"
  }
};


function get_createdtaskId(options,callback){

var res='';

request(options, function (error, response, body) {

    var data=JSON.stringify(body);
    var parsedResponse = JSON.parse(data);
  if (!error && response.statusCode == 200) {
    res = parsedResponse.TaskID;
  }
  else{
  console.log(error);
  res=error;
  }
  callback(res);
});

}

//to call
Task_Id= get_createdtaskId(options, function(resp){ 
    return resp;
});

 return Task_Id;

}

result=Task1();  //1 -->initial function calling

Task2(result){  //3 -->use result from task1 as input parameter for function Task2
//do logic on result received from Task1
}

---

You have to add a callback function to Task 1 which will be called when it is done:

function Task1(callback){  //2 --> Executing task1  
   ....
   callback(result); //get the result this way
};

and then when you call it like this

Task1(function(result){
      Task2(result);
});

This is a very generic approach. Check this to learn more on the subject:

Node.js event-driven

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