Callback not getting called while using collection.save() in async foreach loop in node js

Question

My aim is to save records in a mongoDB collection being in a async foreach loop. Below is the code which speaks for itself.

async.forEach(data, function(item, callback) {
      var object = new Collection_Object();

      // errorLog.push(sdb);
      object.save(function(error) {
        count++;
        console.log(count);
        if(error) {
          console.log("inside error");
          count--;
        }
        //callback();
      });
      callback();
    }, function() {
    //This is the block which should be called after foreach. 
      res.json(data);
  });

Now what is happening is the flow skips the save part and directly jumps to the block which should be called after forEach.

If i am commenting the save part, as expected the callback is working properly. I don't see where i am doing mistake. May be collection.save() isn't suppose to be like this. Please guide.

Might be dup question: http://stackoverflow.com/questions/10390041/node-js-using-the-async-lib-async-foreach-with-object — funcoding, Apr 11 '17 at 11:57
Why have you commented out the callback() call in save()? That's exactly where it should be called. — Stefan Dragnev, Apr 11 '17 at 12:00
I guess, i kept forgetting to uncomment the below callback() function. It worked. Stupid me. — bibliophilsagar, Apr 11 '17 at 12:38

Alessandro · Answer 1 · 2017-04-11T12:10:20.730

1

object.save() is also async, so you have to use callback function with save method, like:

object.save(function(error) {
        count++;
        console.log(count);
        if(error) {
          console.log("inside error");
          count--;
        }
        callback();
      });

edited Apr 11 '17 at 12:10

answered Apr 11 '17 at 12:03

Alessandro

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It should be inside the callback passed to `save()`, not passed as a separate argument. – robertklep Apr 11 '17 at 12:08

Callback not getting called while using collection.save() in async foreach loop in node js

1 Answers1