Parse-server: Parse relation schema mismatch when passing in array of objects

[jiewmeng]

Environment Setup

• Parse Server 2.1.5
• Localhost
• Node 5.5
• Mongo 3.1.9
  

  Steps to reproduce

It seems like the below code in my User's afterSave is causing a problem

feed.relation('forUsers').add(otherUsersInFamily);

otherUsersInFamily is just an array of Parse.User returned by a Parse.Query. When I tried a basic setup creating a Feed and adding forUsers (from a Parse.Query) it works. Its a wierd situation if you need more information please let me know

This particular line is causing an error

schema mismatch for Feed.forUsers; expected relation<_User> but got object

More code

userAfterSave: function(req) {
        var Feed = Parse.Object.extend('Feed');

        var user = req.object;
        var otherUsersInFamily = [];

        if (!user.get('family'))
            return console.log('user not in family', user.id);

        var query = new Parse.Query(Parse.User);
        query.equalTo('family', user.get('family'));
        query.notEqualTo('objectId', user.id);
        query.find()
            .then(function(users) {
                otherUsersInFamily = users;

                if (user.get('joinedFamily') !== true)
                    return;

                var promises = [];

                // add feed
                var feed = new Feed({
                    actor: user.toPointer(),
                    action: 'joined family',
                    title: user.get('family'),
                    subjectType: 'FamilyEvent',
                    subjectAction: 'joined'
                });
                console.log('user id', user.id, otherUsersInFamily)
                feed.relation('forUsers').add(otherUsersInFamily);     // <<< --- When this is commented things no error occur

                return feed.save();
            })
            .fail(function(err) {
                console.error(`User.afterSave Failed: ${user.id}, ${err.message}`);
                return Parse.Promise.error(err.message);
            });
}

[drew-gross]

Can you post the contents of the _User object from your _SCHEMA collection in mongo?

[jiewmeng]

@drew-gross: thats the strange thing, I can't seem to access _* collections in mongo?

> db._SCHEMA.find().pretty()
2016-03-11T14:53:12.141+0800 E QUERY    [thread1] TypeError: db._SCHEMA is undefined :

[jiewmeng]

Ok got it:

{
    "_id" : "_User",
    "username" : "string",
    "password" : "string",
    "email" : "string",
    "dateOfBirth" : "date",
    "family" : "string",
    "firstName" : "string",
    "lastName" : "string",
    "countryCode" : "string",
    "phoneNumber" : "string",
    "gender" : "string",
    "color" : "string",
    "timezone" : "number",
    "image" : "file"
}

For feeds:

{
    "_id" : "Feed",
    "actor" : "*_User",
    "action" : "string",
    "title" : "string",
    "subjectType" : "string",
    "subjectAction" : "string",
    "forUsers" : "relation<_User>"
}

Schema looks ok to me, forUsers should be a relation. The strange thing is AFAIK, I do not assign an object to the relation I always use

• feed.relation('forUsers').add(Parse.User|Array<Parse.User>)

[drew-gross]

Your code looks correct. Does it also fail when you use only a single object? Or does it only fail when you try to save an array?

[jiewmeng]

@drew-gross it fails when I save an array (actually I see the error but it appears the relation is saved fine). Its "OK" (no error) when I save an object:

Except that when I save an object, 1 by one (in a forEach loop), only the first one is saved

[flovilmart]

I'm investigating a bit further

[flovilmart]

Except that when I save an object, 1 by one (in a forEach loop), only the first one is saved

// objects is an array of 10 _User
objects.forEach((user) => {
     owner.relation('toUsers').add(user);
});
return owner.save();

// request
POST /1/classes/Feed { 'user-agent': 'node-XMLHttpRequest, Parse/js1.7.1 (NodeJS 5.3.0)',
  accept: '*/*',
  'content-type': 'text/plain',
  host: 'localhost:8378',
  'content-length': '243',
  connection: 'close' } {
  "toUsers": {
    "__op": "AddRelation",
    "objects": [
      {
        "__type": "Pointer",
        "className": "_User",
        "objectId": "DsvTs15h5C"
      }
    ]
  }
}

This is a parse/node SDK error. cc: @andrewimm

[flovilmart]

@jiewmeng try saving the feed before adding objects to the relation

[flovilmart]

@jiewmeng do you still see the issue or it's fine for you? (besides the problem with the forEach, that seem to reside in the Parse JS SDK)

[drew-gross]

No response in many days, closing.

[loolooii]

I have the same problem using Android SDK. "Schema mismatch, expected [Object object] but got Array."

ArrayList<ParseUser> guests = new ArrayList<ParseUser>();
guests.add(ParseUser.getCurrentUser());
eventObject.put("guests", guests);

// after this I call eventObject.saveInBackground()

[loolooii]

@drew-gross could you confirm that my code is correct? I also tried with ParseObject instead of ParseUser, which also should work, right?

[benishak]

I get the same error when I use destroy!

[fetching]

I also ran into this error but the reason is because I had created Collections in the db and, some time later, I changed the data structure of the Documents I was saving in that same Collection.

Have you changed the structure of any of the Documents since you began writing them to the db?

In my case, I had been using myParseObject.add() to add key/values, which actually performs operations on arrays. I realized later that I needed to use myParseObject.put() in order to simply have a key/value pair rather than an array. And that's when I started getting the error because I was saving to an existing Collection but with a different data structure than what is already saved in the db.

Here's the error I got:

com.parse.ParseRequest$ParseRequestException: schema mismatch for Profile.address; expected [object Object] but got String

To fix the problem:

I'm using a MongoDB and I deleted all Documents in the Collection named Profile. But that wasn't enough. I needed also to go into the _Schema Collection and delete any old definition of the Profile Collection there as well. Once I did that everything began working again.

To troubleshoot you should try changing the Class name of your ParseObject and see if it saves without error.

For example if you have: ParseObject object = new ParseObject("MyProfile")
then try changing it to: ParseObject object = new ParseObject("TestProfile")

If using a new class name for the ParseObject saves without error then you may have old Collections by the original name hanging around the db or in the _Schema. Clean them up and try again.

[mprogers]

Thanks, this solved my problem.

[Edijae]

@fetching how did you delete the schema collection?

db._SCHEMA.remove({})
2019-04-16T11:50:07.349+0000 E QUERY [js] TypeError: db._SCHEMA is undefined : @(shell):1:1

above command never worked