fix(a2a): use protocol-standard contextId as sessionId instead of req…

[pymBupt]

…uiring metadata hardcoded key

Previously, AgentScopeAgentExecutor.getSessionId() read sessionId exclusively from message.metadata["sessionId"], forcing all A2A clients to hardcode this custom metadata key — inappropriate for multi-client interoperability.

The A2A protocol defines Message.contextId as the standard field for session/conversation context tracking.

Changes:

• Prefer contextId (via RequestContext.getContextId()) as the sessionId source
• Fallback to metadata["sessionId"] for backward compatibility
• Add 3 unit tests covering the resolution strategy

Resolves #1603
Related: #820

AgentScope-Java Version

[The version of AgentScope-Java you are working on, e.g. 1.0.12, check your pom.xml dependency version or run mvn dependency:tree | grep agentscope-parent:pom(only mac/linux)]

Description

[Please describe the background, purpose, changes made, and how to test this PR]

Checklist

Please check the following items before code is ready to be reviewed.

• Code has been formatted with mvn spotless:apply
• All tests are passing (mvn test)
• Javadoc comments are complete and follow project conventions
• Related documentation has been updated (e.g. links, examples, etc.)
• Code is ready for review

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[codecov]

Codecov Report

❌ Patch coverage is 75.00000% with 1 line in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
...e/a2a/server/executor/AgentScopeAgentExecutor.java	75.00%	0 Missing and 1 partial ⚠️

📢 Thoughts on this report? Let us know!

[AgentScopeJavaBot]

🤖 AI Review

This PR changes AgentScopeAgentExecutor.getSessionId() to prefer the A2A protocol-standard Message.contextId field over the custom metadata["sessionId"] key, while maintaining backward compatibility via fallback. This correctly addresses issue #1603 where all A2A clients were forced to hardcode a custom metadata key. The change is minimal (~24 lines in production code), backward-compatible, and well-documented with Javadoc. Three new unit tests cover the priority resolution strategy. The direction is correct and the implementation is clean. Minor suggestion: add test coverage for the edge case where context.getContextId() returns null.

[AgentScopeJavaBot]

[recommended] Test coverage gap: The existing 3 tests cover contextId present, metadata fallback, and both present. Consider adding a test for the edge case where context.getContextId() returns null (not empty string) and no metadata sessionId exists — verifying the method returns empty string. This path is handled correctly in the code (contextId != null check) but has no test.

[AgentScopeJavaBot]

[nitpick] Test code duplication: The three test cases share extensive mock setup boilerplate (MessageSendParams mock, AtomicReference<AgentRequestOptions> capture, mockAgentRunner.stream stubbing, executor.execute call). Consider extracting a private helper method like executeAndCaptureOptions(contextId, metadataMap) to reduce duplication.

[AgentScopeJavaBot]

🤖 AI Review

This PR changes AgentScopeAgentExecutor.getSessionId() to prefer the A2A protocol-standard Message.contextId field over the custom metadata["sessionId"] key, while maintaining backward compatibility via fallback. This correctly addresses issue #1603 where all A2A clients were forced to hardcode a custom metadata key. The change is minimal (~24 lines in production code), backward-compatible, and well-documented with Javadoc. Three new unit tests cover the priority resolution strategy. The direction is correct and the implementation is clean. Minor suggestion: add test coverage for the edge case where context.getContextId() returns null.

[AgentScopeJavaBot]

[recommended] Test coverage gap: The existing 3 tests cover contextId present, metadata fallback, and both present. Consider adding a test for the edge case where context.getContextId() returns null (not empty string) and no metadata sessionId exists — verifying the method returns empty string. This path is handled correctly in the code (contextId != null check) but has no test.

[AgentScopeJavaBot]

[nitpick] Test code duplication: The three test cases share extensive mock setup boilerplate (MessageSendParams mock, AtomicReference<AgentRequestOptions> capture, mockAgentRunner.stream stubbing, executor.execute call). Consider extracting a private helper method like executeAndCaptureOptions(contextId, metadataMap) to reduce duplication.