feat(data-schema): accept null to disable queryField for secondary indexes

[naedx]

Problem

There was previously no way to disable the top-level query field that was automatically created when a secondary index is created. This PR adds support for passing null as in index(...).queryField(null) to disable the query field. This is consistent with the configuration described since Gen1

export const schema = a.schema({
  Customer: a
    .model({
      name: a.string(),
      phoneNumber: a.phone(),
      accountRepresentativeId: a.id().required(),
    })
    .secondaryIndexes(
        (index) => [
            index("accountRepresentativeId")
                 .sortKeys(["name"])
                 .queryField(null)            //<<< added support for null to be passed
        ]
    )
    .authorization(allow => [allow.publicApiKey()]),
});

Issue number, if available:

#566

Changes

Corresponding docs PR, if applicable:

Validation

Unit tests have been included to validate a similar behaviour to Gen1

• Current (unchanged) behavior:
  • queryField('someName') results in a query field called 'someName'
  • queryField() not called results in a query field with default naming
• Changed behavior:
  • queryField(null) results in the query field being set to null

Checklist

• If this PR includes a functional change to the runtime or type-level behavior of the code, I have added or updated automated test coverage for this change. (see Testing Strategy README)
• If this PR requires a docs update, I have linked to that docs PR above.

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[changeset-bot]

🦋 Changeset detected

Latest commit: 8e8af6f

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@aws-amplify/data-schema	Minor

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[naedx]

Note that the changes maintain the Gen1 behaviour which requires explicitly defining queryField: null otherwise the default queryField with the default name is created.

As such, the PR changes .queryField(string) to .queryField(string | null) where null has to be given explicitly to disable the field (like Gen1). This is backwards compatible with any existing user code since it would not change the behavior of existing usage (or non-usage) of the queryField method.