Parse to Heroku migration (MongoLab): PFRelation issue

Question

I succeeded to migrate parse to parse-server with mongolab. Now everything works as expected, except when I'm logging with PFUser with MongoLab, my PFRelation object is always null.

In my AppDelegate, when I run this code (official Parse):

[Parse setApplicationId:@"xxxxxx"
              clientKey:@"xxxxxx"];
[PFUser enableRevocableSessionInBackground];

HomeView.m:

self.currentUser = [PFUser currentUser];
self.friendsRelation = [[PFUser currentUser] objectForKey:@"friends"];
NSLog(@"%@", self.currentUser);
NSLog(@"%@", self.friendsRelation);

After login, my HomeView log this:

2016-02-28 23:25:38.756 ChillN[4131:57119] <PFUser: 0x7fe0b3e4fc10, objectId: MZdPHaqByR, localId: (null)> {
    friends = "<PFRelation: 0x7fe0b3e4f900, 0x7fe0b3e4fc10.friends -> _User>";
    phone = "06 19 05 39 30";
    surname = a;
    username = a;
}
2016-02-28 23:25:38.756 ChillN[4131:57119] <PFRelation: 0x7fe0b3e4f900, 0x7fe0b3e4fc10.friends -> _User>

So everything's right.

Now with the mongolab db:

AppDelegate:

[Parse initializeWithConfiguration:[ParseClientConfiguration configurationWithBlock:^(id<ParseMutableClientConfiguration> configuration) {
    configuration.applicationId = @"xxxxxxx";
    configuration.clientKey = @"xxxxxxx";
    configuration.server = @"http://xxxxxxx.herokuapp.com/parse/";
}]];

After my login, my HomeView log this:

2016-02-28 23:29:21.785 ChillN[4281:59046] <PFUser: 0x7fa43c09ed20, objectId: MZdPHaqByR, localId: (null)> {
    phone = "06 19 05 39 27";
    surname = a;
    username = a;
}
2016-02-28 23:29:21.786 ChillN[4281:59046] (null)

For logging, I'm just using:

[PFUser logInWithUsernameInBackground:user
                                 password:password block:^(PFUser *user, NSError *error) {}];

Here are my db: Parse:

Heroku (MongoLab):

Here is a record for User from MongoLab:

{
    "_id": "MZdPHaqByR",
    "_perishable_token": "SHuhtWl0EoxxmNLOkspmp1vBF",
    "username": "a",
    "phone": "06 19 05 39 27",
    "surname": "a",
    "_session_token": "zO2drjzrO0To1q0JiohaL8f4v",
    "_hashed_password": "$2a$10$a7j5yB7uFDtv.YnHESVJgO9Io.nci8hbx7vngOo.FyzA3qBLxw38G",
    "_created_at": {
        "$date": "2016-02-28T21:55:48.548Z"
    },
    "_updated_at": {
        "$date": "2016-02-28T22:03:45.704Z"
    }
}

Answer 1

It was just a mistake in my code, I had to replace:

self.friendsRelation = [[PFUser currentUser] objectForKey:@"friends"];

to

self.friendsRelation = [[PFUser currentUser] relationForKey:@"friends"];

Hope that will help another one. Cheers!