Amplify Gen 2 model creation problem

[ozguraltunsogut]

Hello,
I prepared two simple models below,
const schema = a.schema({
Users: a
.model({
id: a.id().required(),
name: a.string(),
eMail: a.string(),
gsm: a.string(),
nickName: a.string(),
motto: a.string(),
introduction: a.string(),
messagesReceived: a.hasMany("Messages", "user1Id"),
messagesSent: a.hasMany("Messages", "user2Id")

  }
).authorization((allow) => allow.authenticated("userPools")),
Messages: a
.model({
  user1Id: a.id().required(),
  user1: a.belongsTo("Users", "user1Id"),
  messageDate: a.datetime().required(),
  messageBody: a.string().required(),
  user2Id: a.id().required(),
  user2: a.belongsTo("Users", "user2Id"),
  messageType: a.string().required(),
  isRead: a.boolean().default(false),
  readDate: a.datetime()
})
.identifier(["user1Id", "messageDate"])
.authorization((allow) => allow.authenticated("userPools"))

});

When I run the command "npx ampx generate graphql-client-code --format modelgen --model-target dart --out ./lib/models" to generate GraphQL client codes, code gen doesn't create a property userId2 for Messages model as below.
/** This is an auto generated class representing the Messages type in your schema. */
class Messages extends amplify_core.Model {
static const classType = const _MessagesModelType();
final String? _user1Id;
final Users? _user1;
final amplify_core.TemporalDateTime? _messageDate;
final String? _messageBody;
final Users? _user2;
final String? _messageType;
final bool? _isRead;
final amplify_core.TemporalDateTime? _readDate;
final amplify_core.TemporalDateTime? _createdAt;
final amplify_core.TemporalDateTime? _updatedAt;

I have defined hasMany and belongsTo properties for both user1Id and user2Id. user1Id created but user2Id not.
Is there anyone has any idea about this problem?

Best regards.

[ekjotmultani]

Hi @ozguraltunsogut, thanks for opening this issue, we will investigate and provide an update when we have one

[tyllark]

Hello @ozguraltunsogut, the final String? _user1Id; field is only present in your model because it is included in your identifier method .identifier(["user1Id", "messageDate"]). Typically the reference field in your belongsTo relationship is not included in your model as is the case for your user2Id and user2.

If you are looking to access the value of user2Id you can retrieve it from the user2 instance:

String? getUser2Id(Messages message) {
  return message.user2?.id;
}

Please let us know if this answers your question.

[ozguraltunsogut]

Hello @tyllark, This means if I want to filter messages that belongs to user2Id, I have to join the Users table and filter it by user2.id = '.....'
Yes this is possible but why I have to join the Users table to find messages for User2?
If this is not possible I will add another field that holds the user2Id like User2IdValue
Best regards.

[tyllark]

Hello @ozguraltunsogut, sorry for the delay. While user2Id is not present in the generated Messages.dart model it can still be referenced in your GraphQL documents. You can create your own GraphQL document from scratch as shown in our GraphQL advanced workflow docs or you can leverage some of our existing GraphQL document generating APIs that handle filtering:

Future<List<Messages?>?> _queryMessagesByUser2Id(String user2Id) async {
    final request = ModelQueries.list(
      Messages.classType,
      where: QueryField(fieldName: "user2Id").eq(user2Id),
      authorizationMode: APIAuthorizationType.userPools,
    );

    final response = await Amplify.API.query(request: request).response;
    final messages = response.data?.items;
    return messages;
  }