async.each doesn't run callback function

Question

I'm trying to do something after push data from reddit api to array, but callback function doesn't work at all. As you see the code, It's supposed to print Callback function works! but It doesn't. Is there any ideas about this?

let optForReddit = {
  method: 'GET',
  uri: 'https://www.reddit.com/domain/eroshare.com/new.json',
  json: true
}

  rp(optForReddit)
    .then(function(redditJSON) {
      let posts = redditJSON.data.children;
      let len = posts.length;
      let eroJson = [];
      async.each(posts, function(item, callback) {
          if (isVideo(item.data.url)) {
            eroJson.push(getAlbumId(item.data.url));
          }
      },    
      function(err) {
          console.log("Callback function works");
          if(err) console.log(err);
      });
    })
    .catch(function(err) {
      console.log(err);
    })

Asif Saeed · Accepted Answer · 2017-02-12T07:42:26.760

1

async.each(posts, function(item, callback) {
      if (isVideo(item.data.url)) {
        eroJson.push(getAlbumId(item.data.url));
      }
      callback();  // this callback is for informing that i am done processing one item in array.
  },    
  function(err) {
      //this function will be invoked when the callback() in the above body was called maximum time(e.g posts.length times)
      console.log("Callback function works");
      if(err) console.log(err);
  });

this is because you are not calling callback function each time. callback when called tells the async function that i am done with the current execution and call next iteraion. You never called the callback().

edited Feb 12 '17 at 07:42

answered Feb 12 '17 at 07:29

Asif Saeed

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but I want to call the callback function after the each loop is done. how can I do? – boombamboo Feb 12 '17 at 07:35
like you want to execute loop serially? so it executes in order? – Asif Saeed Feb 12 '17 at 07:36
yes! so the callback function can run after everything is done. – boombamboo Feb 12 '17 at 07:38
I solved the problem! I just had to use `eachSeries` not `each`. Thank you for help anyways! – boombamboo Feb 12 '17 at 07:42
I have a question, eachSeries in waterfall would work or not? – boombamboo Feb 12 '17 at 07:56
`async.eachSeries` only called once. do you have any idea about it? my code is here http://pastebin.com/uK45fRzT. even though the length of posts is 25. – boombamboo Feb 12 '17 at 08:24
this is baecause you are still not calling the callback function. if you are not calling the callback function how would async know that one iteration is done? – Asif Saeed Feb 12 '17 at 08:27
oh my god i was being so dumb lol Thank you so much! Have a nice weekend though its sunday! – boombamboo Feb 12 '17 at 08:29
look at my answer above. see where i am calling callback. you are doing same with the async.eachSeries – Asif Saeed Feb 12 '17 at 08:29
I did! :) Thank you – boombamboo Feb 12 '17 at 08:34

async.each doesn't run callback function

1 Answers1