Can not set a nullable string index to null

[osehmathias]

Description

I have schema like this

type Entry @model {
  id: ID!
  draftRecordID: ID @index
  }

With Amplify GraphQL, I can set draftRecordID to null.

With Amplify DataStore, I can not, even with
entry.copyWithModelFieldValues(draftRecordID: const ModelFieldValue.value(null));

Categories

• Analytics
• API (REST)
• API (GraphQL)
• Auth
• Authenticator
• DataStore
• Notifications (Push)
• Storage

Steps to Reproduce

Create schema with a nullable String index. Set the String index field to a value. Attempt to remove that value by setting it to null.

Screenshots

No response

Platforms

• iOS
• Android
• Web
• macOS
• Windows
• Linux

Flutter Version

3.19.1

Amplify Flutter Version

1.6.1

Deployment Method

Amplify CLI

Schema

type Entry {
  id: ID!
  draftRecordID: ID @index
  }

[NikaHsn]

Sorry that you are facing this issue and thanks for reporting it. We will look into this and get back to you when we have updates.

[osehmathias]

@NikaHsn - thanks, although I think it is a DataStore issue, not a GraphQL issue, as I experience this error with DataStore but not GraphQL.

[Equartey]

Hi @osehmathias, I am unable to reproduce this.

.copyWithModelFieldValues() returns a new instance of the model which needs to be saved. This example works for me.

final entry = Entry(draftRecordID: 'foo');
print('Before: ${entry.draftRecordID}'); // Before: foo
final newEntry = entry.copyWithModelFieldValues(
    draftRecordID: const ModelFieldValue.value(null),
);
print('After: ${newEntry.draftRecordID}'); // After: null

Can you confirm how you are calling the copy method?

---

Also I noticed your schema Entry should have the @model decorator. I don't think this is causing issues, but it may have other side effects later on.

type Entry @model {
  id: ID!
  draftRecordID: ID @index
}

[osehmathias]

Hi @Equartey

I am calling the copy method like so:

final entry = Entry(draftRecordID: 'foo');
print('Before: ${entry.draftRecordID}'); // Before: foo
final newEntry = entry.copyWithModelFieldValues(
    draftRecordID: const ModelFieldValue.value(null),
);
print('After: ${newEntry.draftRecordID}'); // After: null
await Amplify.DataStore.save(newEntry);

// now fetch .... 

Entry fetchedEntry = await Amplify.DataStore.query(Entry.classType, where xxxx)
print('Fetched: ${fetchedEntry.draftRecordID}'); // Fetched entry, not cleared

---

Also I noticed your schema Entry should have the @model decorator. I don't think this is causing issues, but it may have other side effects later on.

Thank you. It does have the @model decorator. I edited it down when I posted the issue.

[Equartey]

Hi @osehmathias

My apologies, I cannot reproduce this. I successfully nullified the property when saving before and after.

I tested on both iOS and Android with the same Flutter and Amplify versions. Here is my function & schema:

  Future<void> copyTest() async {
    final entry = Entry(draftRecordID: 'foo');
    print('Before: ${entry.draftRecordID}'); // Before: foo

    await Amplify.DataStore.save(entry);

    final resBefore = await Amplify.DataStore.query(Entry.classType,
        where: Entry.ID.eq(entry.id));
    print('resBefore: $resBefore'); // resBefore: Entry.draftRecordID = baz

    final newEntry = entry.copyWithModelFieldValues(
      draftRecordID: const ModelFieldValue.value(null),
    );
    print('After: ${newEntry.draftRecordID}'); // After: null

    await Amplify.DataStore.save(newEntry);

    final resAfter = await Amplify.DataStore.query(Entry.classType,
        where: Entry.ID.eq(entry.id));
    print('resAfter: ${resAfter}'); // resAfter: Entry.draftRecordID = null
  }

type Entry @model {
  id: ID!
  draftRecordID: ID @index
}

I'm not sure what could be the issue or different about our environments.

Can you confirm the ID's of the entries match?

Is there anything else specific with your setup that would help me reproduce the issue?

[osehmathias]

Hi @Equartey - I can see in the xcode logs that it sets it to null

"draftRecordID": Amplify.JSONValue.null,

However, when I refetch, the value is still there.

I have been able to get around this by setting the value of draftRecordID to '-' instead of null.