Mongoose .create( ) not saving entries to db

Question

My seed file is supposed to seed 2 users into my MongoDB. My db.User.remove( ) is definitely deleting any existing users in my db, so I am accessing the right db. However, newUser.save( ) isn't actually saving records.

My console.log is showing that my 2 user objects from user_list have been generated, but my newUser.save( ) is not actually saving new records to the User collection (it's completely empty). Any ideas?

seed.js

// remove all users
db.User.remove({}, function(err, users){
    if(err) {
    console.log('Error occurred in remove', err);
    } else {
        console.log('removed all users');
        // create new records based on the array user_list
        for (i=0; i < user_list.length; i++) {
            var newUser = new User();
            // set the user's local credentials
            newUser.email = user_list[i].email;
            newUser.password = createHash(user_list[i].password);
            newUser.company = user_list[i].company;
            newUser.firstName = user_list[i].firstName;
            newUser.lastName = user_list[i].lastName;
            newUser.admin = user_list[i].admin;
            console.log(newUser);
            // save the user
            newUser.save(function(err, users) {
                if (err){
                    console.log('Error in Saving user: '+ err);  
                    throw err; 
                } 
            });
        }
        console.log("created", user_list.length, "users");
        process.exit();
    }
});

Note: [Asynchronous for cycle in JavaScript](https://stackoverflow.com/questions/4288759/asynchronous-for-cycle-in-javascript) — Jonathan Lonowski, Aug 28 '16 at 20:31

score 1 · Accepted Answer · answered Aug 28 '16 at 20:23

1

save operation is asynchronous(non-blocking) and as a result, process.exit(); will be executed earlier then save operation. user_list seems to an array with static data. Try to log users variable or just any marker in save callback instead.

The way to fix it is to aggregate and use promises or place check for the last user in save callback.

answered Aug 28 '16 at 20:23

G07cha

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Actually, found a solution. This put me on the right track. Thanks! – gbru015 Aug 28 '16 at 20:59

gbru015 · Answer 2 · 2016-08-28T21:20:51.277

As Konstantin mentioned, process.exit( ) was getting called before save. There are better solutions, but simple answer was to delay the process.exit( ) by adding a counter:

// remove all users
db.User.remove({}, function(err, users){
    if(err) {
    console.log('Error occurred in remove', err);
    } else {
        console.log('removed all users');
        // create new records based on the array user_list
        var count = 1;
        for (i=0; i < user_list.length; i++) {
            var newUser = new User();
            // set the user's local credentials
            newUser.email = user_list[i].email;
            newUser.password = createHash(user_list[i].password);
            newUser.company = user_list[i].company;
            newUser.firstName = user_list[i].firstName;
            newUser.lastName = user_list[i].lastName;
            newUser.admin = user_list[i].admin;
            console.log(newUser);
            // save the user
            newUser.save(function(err, users) {
                count += 1;
                if (err){
                    console.log('Error in Saving user: '+ err);  
                    throw err; 
                } else if (count == user_list.length) {
                    process.exit();
                }
            });
        }
        console.log("created", user_list.length, "users");
    }
});

Have you tried running code without `process.exit()`? Because current code doesn't delay anyhow, it just performs a check and if it fails, skips `process.exit()`. — G07cha, Aug 28 '16 at 21:01
Yes, it freezes without an exit. I think, because the count iteration isn't happening until the save callback (save has already run), then process.exit( ) is ignored until after 2 saves (or as many saves as my user_list is long). Do you know of a cleaner solution? — gbru015, Aug 28 '16 at 21:05
Yeah, as I mentioned in an answer, you should move check that you've just created inside `save` callback. — G07cha, Aug 28 '16 at 21:07

Mongoose .create( ) not saving entries to db

2 Answers2