[cloud_firestore] error-Invalid argument (dartObject): Could not convert: Instance of 'Timestamp'

[kushvatsa]

Hey @ditman , While doing pagination on flutter web, cloud firestore gives error error-Invalid argument (dartObject): Could not convert: Instance of 'Timestamp'

try {
      Firestore fireStore = Firestore.instance;
      final QuerySnapshot docs = await fireStore
          .collectionGroup("vote")
          .where("uid", isEqualTo: uid)
          .orderBy(fieldVal, descending: true)
          .startAfterDocument(doc)
          .limit(2)
          .getDocuments();
 } catch (e) {
      print("error-" + e.toString());
      return null;
    }

[iapicca]

Hi @kushvatsa
can you please provide your flutter doctor -v ,
your flutter run --verbose
and your pubspec.yaml
or if possible a reproducible minimal code sample.
Thank you

[ditman]

@kushvatsa can you also describe a little bit the data structures you're using? Is the Timestamp failing in the startAfterDocument line, or elsewhere?

Is this because your doc contains a Timestamp type?

[kushvatsa]

  final String fieldVal = 'created_time';
  DocumentSnapshot doc;

initData() async {
    try {
      final docs = await Firestore.instance
          .collectionGroup("vote")
          .where("uid", isEqualTo: uid)
          .orderBy(fieldVal, descending: true)
          .limit(2)
          .getDocuments();
      doc = docs.documents.first;
    } catch (e) {
      print("error-" + e.toString());
      return null;
    }
  }

  nextData() async {
    try {
      Firestore fireStore = Firestore.instance;
      await fireStore
          .collectionGroup("vote")
          .where("uid", isEqualTo: uid)
          .orderBy(fieldVal, descending: true)
          .startAfterDocument(doc)
          .limit(2)
          .getDocuments();
    } catch (e) {
      print("error-" + e.toString());
      return null;
    }
  }

@ditman , yes. TimeStamp failing in the startAfterDocument and also in the endBeforeDocument.

[kushvatsa]

@iapicca , check the above comment. Thanks!

[iapicca]

Hi @kushvatsa
could you please provide these info
thank you

[ditman]

@iapicca no need, this comes from a past issue where I asked @kushvatsa to start a new one. This issue can be reproduced by the tests of the _web plugin. I'll get on this ASAP. Thanks!

[iapicca]

Thank for the clarification @ditman

[ditman]

The current tests can reproduce this issue:

00:07 +7: Firestore pagination [E]
Invalid argument (dartObject): Could not convert: Instance of 'Timestamp'
package:dart-sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/errors.dart 196:49      throw_
  package:firebase/src/utils.dart 119:3                                                     jsify
  package:dart-sdk/lib/internal/iterable.dart 417:29                                        elementAt
  package:dart-sdk/lib/internal/iterable.dart 221:19                                        toList
  package:firebase/src/firestore.dart 552:22
  [_wrapPaginatingFunctionCall]
  package:firebase/src/firestore.dart 523:11                                                startAt
  package:cloud_firestore_web/src/query_web.dart 180:17                                     startAtDocument
  package:cloud_firestore/src/query.dart 130:17                                             startAtDocument
  package:firestore_example/main.dart 193:48                                                <fn>

The error happens here.

Investigating.