Get Query Using TemporalDateTime Objects

[Maanasaaaaa]

Environment information

System:
  OS: macOS 15.5
  CPU: (10) arm64 Apple M4
  Memory: 174.03 MB / 16.00 GB
  Shell: /bin/zsh
Binaries:
  Node: 20.19.3 - ~/.nvm/versions/node/v20.19.3/bin/node
  Yarn: undefined - undefined
  npm: 10.8.2 - ~/.nvm/versions/node/v20.19.3/bin/npm
  pnpm: undefined - undefined
NPM Packages:
  @aws-amplify/auth-construct: 1.8.1
  @aws-amplify/backend: 1.16.1
  @aws-amplify/backend-ai: Not Found
  @aws-amplify/backend-auth: 1.7.1
  @aws-amplify/backend-cli: 1.8.0
  @aws-amplify/backend-data: 1.6.1
  @aws-amplify/backend-deployer: 2.1.3
  @aws-amplify/backend-function: 1.14.1
  @aws-amplify/backend-output-schemas: 1.7.0
  @aws-amplify/backend-output-storage: 1.3.1
  @aws-amplify/backend-secret: 1.4.0
  @aws-amplify/backend-storage: 1.4.1
  @aws-amplify/cli-core: 2.2.1
  @aws-amplify/client-config: 1.8.0
  @aws-amplify/data-construct: 1.16.3
  @aws-amplify/data-schema: 1.21.1
  @aws-amplify/deployed-backend-client: 1.8.0
  @aws-amplify/form-generator: 1.2.4
  @aws-amplify/model-generator: 1.2.0
  @aws-amplify/platform-core: 1.10.0
  @aws-amplify/plugin-types: 1.11.0
  @aws-amplify/sandbox: 2.1.2
  @aws-amplify/schema-generator: 1.4.0
  @aws-cdk/toolkit-lib: 1.1.1
  aws-amplify: 6.15.5
  aws-cdk-lib: 2.204.0
  typescript: 5.9.2
npm warn exec The following package was not found and will be installed: cdk@2.1024.0
No AWS environment variables
No CDK environment variables

Describe the bug

1. When using Amplify's ModelQueries.get() in a Flutter application with a schema that includes a TemporalDateTime field, the query fails with a JsonUnsupportedObjectError. This occurs when attempting to serialize a TemporalDateTime object for a GraphQL request.

[+] Error: JsonUnsupportedObjectError (Converting object to an encodable object failed: Instance of 'TemporalDateTime')

2. This issue creates a conflict between the schema definition, which uses TemporalDateTime, and the actual query execution, which cannot serialize these objects. It's particularly problematic because the TemporalDateTime type is provided by the Amplify library itself, suggesting it should be fully supported.

3. A workaround involves replacing TemporalDateTime with standard Dart DateTime objects and creating a custom model identifier, but this shouldn't be necessary given that TemporalDateTime is a supported type in the schema.

Reproduction steps

1. Create a Flutter application using Amplify CLI Gen2 with the following schema:

Metrics: a
    .model({
      hwid: a.string().required(),
      sessionStart: a.datetime().required(),
      // other fields...
    })
    .identifier(["hwid", "sessionStart"])
    .secondaryIndexes((index) => [index("sessionStart").queryField("listByDate")])
    .authorization((allow) => [allow.authenticated()])

2. Generate the models using Amplify CLI.
3. Attempt to query the data using ModelQueries.get():

final hwid = "94B216FCC67F";
final dateKey = "2025-03-28T23:07:34.000Z";
final request = ModelQueries.get(
      Metrics.classType,
      Metrics(hwid: hwid, sessionStart: TemporalDateTime.fromString(dateKey))
          .modelIdentifier,
    );
final response = await Amplify.API.query(request: request).response;

4. Run the query. It will fail with the JsonUnsupportedObjectError mentioned above.

[svidgen]

Unless I'm misunderstanding, I think this belongs in the flutter repo. I don't have permission to transfer to that one anymore, but I believe someone in the JS repo should be able to. Transferring there.

[ekjotmultani]

Hi, thank you for raising the issue, we are investigating