DGS-23025 Add AssociatedNameStrategy

[Robert Yokota (rayokota)]

What

• Add AssociatedNameStrategy, which is now the default
• Add async subject-name strategy delegate pipeline (serdes now await subject resolution)
• Add tests

Checklist

• [Y] Contains customer facing changes? Including API/behavior changes
• [Y] Did you add sufficient unit test and/or integration test coverage for this PR?
  • If not, please explain why it is not required

References

JIRA:

Test & Review

Open questions / Follow-ups

[Copilot]

Pull request overview

This PR introduces an “Associated” subject name strategy that resolves the Schema Registry subject for a topic via Schema Registry associations, and wires the serdes to use an async subject naming delegate to support this lookup.

Changes:

• Added SubjectNameStrategy.Associated plus an async subject-name strategy delegate pipeline (serdes now await subject resolution).
• Added Schema Registry REST + client APIs for association CRUD / lookup, and corresponding data contracts.
• Added unit tests and mock support to validate associated subject resolution, fallback behavior, and kafka-cluster-namespace behavior.

Reviewed changes

Copilot reviewed 23 out of 23 changed files in this pull request and generated 13 comments.

Show a summary per file

File	Description
test/Confluent.SchemaRegistry.Serdes.UnitTests/SerializeDeserialize.cs	Adds unit tests covering Associated strategy behavior and fallback.
test/Confluent.SchemaRegistry.Serdes.UnitTests/BaseSerializeDeserialize.cs	Extends mock Schema Registry client to support association lookups used by tests.
src/Confluent.SchemaRegistry/SubjectNameStrategy.cs	Adds async subject strategy delegate, Associated strategy implementation, and ToAsyncDelegate.
src/Confluent.SchemaRegistry/Rest/RestService.cs	Adds REST calls for association lookup/create/delete and a void-request helper.
src/Confluent.SchemaRegistry/Rest/IRestService.cs	Exposes association REST endpoints to the internal REST service interface.
src/Confluent.SchemaRegistry/Rest/DataContracts/Association.cs	New association DTO for REST responses.
src/Confluent.SchemaRegistry/Rest/DataContracts/AssociationInfo.cs	New association info DTO for create/update responses.
src/Confluent.SchemaRegistry/Rest/DataContracts/AssociationResponse.cs	New DTO for create/update association responses.
src/Confluent.SchemaRegistry/Rest/DataContracts/AssociationCreateOrUpdateRequest.cs	New DTO for create/update association requests.
src/Confluent.SchemaRegistry/Rest/DataContracts/AssociationCreateOrUpdateInfo.cs	New DTO for association create/update items.
src/Confluent.SchemaRegistry/ISchemaRegistryClient.cs	Adds association APIs to the public client interface.
src/Confluent.SchemaRegistry/CachedSchemaRegistryClient.cs	Implements the new association APIs via RestService.
src/Confluent.SchemaRegistry/AsyncSerde.cs	Switches serdes to use an async subject name delegate and await subject resolution.
src/Confluent.SchemaRegistry.Serdes.Protobuf/ProtobufSerializer.cs	Uses ToAsyncDelegate and allows strategy.* configs.
src/Confluent.SchemaRegistry.Serdes.Protobuf/ProtobufDeserializer.cs	Uses ToAsyncDelegate and allows strategy.* configs.
src/Confluent.SchemaRegistry.Serdes.Json/JsonSerializer.cs	Uses ToAsyncDelegate and allows strategy.* configs.
src/Confluent.SchemaRegistry.Serdes.Json/JsonDeserializer.cs	Uses ToAsyncDelegate and allows strategy.* configs.
src/Confluent.SchemaRegistry.Serdes.Avro/SpecificSerializerImpl.cs	Awaits async subject name resolution.
src/Confluent.SchemaRegistry.Serdes.Avro/SpecificDeserializerImpl.cs	Awaits async subject name resolution.
src/Confluent.SchemaRegistry.Serdes.Avro/GenericSerializerImpl.cs	Awaits async subject name resolution.
src/Confluent.SchemaRegistry.Serdes.Avro/GenericDeserializerImpl.cs	Awaits async subject name resolution.
src/Confluent.SchemaRegistry.Serdes.Avro/AvroSerializer.cs	Allows strategy.* configs (validation change).
src/Confluent.SchemaRegistry.Serdes.Avro/AvroDeserializer.cs	Allows strategy.* configs (validation change).

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Pull request overview

Copilot reviewed 23 out of 23 changed files in this pull request and generated 8 comments.

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Copilot reviewed 23 out of 23 changed files in this pull request and generated 9 comments.

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Copilot reviewed 23 out of 23 changed files in this pull request and generated 5 comments.

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Copilot reviewed 25 out of 25 changed files in this pull request and generated 3 comments.

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Pull request overview

Copilot reviewed 25 out of 25 changed files in this pull request and generated 1 comment.

Comments suppressed due to low confidence (1)

src/Confluent.SchemaRegistry.Serdes.Protobuf/ProtobufDeserializer.cs:148

• The code instantiates new T() twice in this method: once at line 139 to get the Descriptor.FullName, and again at line 148 to create the actual message object. This is wasteful and could cause issues if the constructor has side effects or is expensive. Consider moving the second GetSubjectName call to after line 148 and using message.Descriptor.FullName instead of creating a new instance. This would reduce unnecessary object allocation and potential side effects.

                    if (subject == null)
                    {
                        subject = await GetSubjectName(topic, isKey, new T().Descriptor.FullName).ConfigureAwait(false);
                    }
                }
                payload = await ExecuteRules(context.Component == MessageComponentType.Key,
                        subject, context.Topic, context.Headers, RulePhase.Encoding, RuleMode.Read,
                        null, writerSchema, payload, null)
                    .ContinueWith(t => t.Result is byte[] bytes ? new ReadOnlyMemory<byte>(bytes) : (ReadOnlyMemory<byte>)t.Result)
                    .ConfigureAwait(continueOnCapturedContext: false);

                message = new T();

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Copilot reviewed 25 out of 25 changed files in this pull request and generated 7 comments.

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Copilot reviewed 25 out of 25 changed files in this pull request and generated 9 comments.

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[sonarqube-confluent]

Quality Gate failed

Failed conditions
44.1% Coverage on New Code (required ≥ 80%)

See analysis details on SonarQube

[sonarqube-confluent]

Quality Gate failed

Failed conditions
44.1% Coverage on New Code (required ≥ 80%)

See analysis details on SonarQube