Nodejs: call api and get data in ordered form

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I have an Array of elements and I need to loop over them getting a value from a server at each pass. With the following code I am getting all the results mixed, due to the asynchronous call in the forEach loop. I need the results to be shown in the same order as in the Array.

var en_devices= [
  ["72", "Device 1"],
  ["73", "Device 2"],
  ["74", "Device 3"],
  ["75", "Device 4"],
  ["76", "Device 5"],
  ["5158", "Device 6"]
];

en_devices.forEach(element => {
    $.get('/check-energy/'+element[0], function(data){
      content = "<div class='service'>"+element[1]+"</div> <div class='watt'>"+data+"</div><br/>";
      $('#description-en').append(content);
  });
 });
node.js jquery javascript
1 Answers

You should try for loop with await

var en_devices= [
  ["72", "Device 1"],
  ["73", "Device 2"],
  ["74", "Device 3"],
  ["75", "Device 4"],
  ["76", "Device 5"],
  ["5158", "Device 6"]
];

Create a function that returns a promise so that you can await it

function getData(element) {
    return new Promise((resolve, reject) => {
      $.get('/check-energy/'+element[0], function(data) {
        resolve(data)
    })
})
}

Now run a for loop

let content="";
for(let i=0;i<en_devices.length;i++)
{
let data=await getData(en_devices[i])
content += "<div class='service'>"+element[1]+"</div> <div class='watt'>"+data+"</div><br/>";
     
}


$('#description-en').append(content);

async wait doesn't works in forEach loop ,you can either use for of or for loop

user_78495490
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