test(samples): [Queue Instrumentation 6] Add Kafka queue system tests

[adinauer]

PR Stack (Queue Instrumentation)

• feat(core): [Queue Instrumentation 1] Add enableQueueTracing option and messaging span data conventions #5250
• feat(samples): [Queue Instrumentation 2] Add Kafka to Spring Boot 3 sample app #5253
• feat(spring-jakarta): [Queue Instrumentation 3] Add Kafka producer instrumentation #5254
• feat(spring-jakarta): [Queue Instrumentation 4] Add Kafka consumer instrumentation #5255
• feat(spring-boot-jakarta): [Queue Instrumentation 5] Add Kafka queue auto-configuration #5259
• → test(samples): [Queue Instrumentation 6] Add Kafka queue system tests #5260

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📜 Description

Add end-to-end system tests for Kafka queue instrumentation in the Spring Boot 3 sample app:

• KafkaQueueSystemTest — 5 tests covering:

  • Producer endpoint creates queue.publish span
  • Consumer creates queue.process transaction
  • Distributed tracing: producer and consumer share the same trace ID
  • queue.publish span has messaging.system=kafka and messaging.destination.name=sentry-topic
  • queue.process transaction has matching messaging attributes

• RestTestClient.produceKafkaMessage — new helper method for hitting the /kafka/produce endpoint

• application-kafka.properties — adds sentry.enable-queue-tracing=true to the kafka profile

💡 Motivation and Context

PR 6 in the Queue Instrumentation stack. Validates the full stack (producer → consumer → auto-config) works end-to-end before moving to OTel and ports. Follows the existing CacheSystemTest pattern.

Infrastructure note: These tests require a running Kafka broker at localhost:9092 and the sample app started with --spring.profiles.active=kafka. They won't run in the standard CI flow until Kafka infrastructure is added to the system test pipeline.

💚 How did you test it?

• Compilation verified: ./gradlew :sentry-samples:sentry-samples-spring-boot-jakarta:compileTestKotlin
• Full e2e validation requires running Kafka + sample app (not automated yet)

📝 Checklist

• I added GH Issue ID & Linear ID
• I added tests to verify the changes.
• No new PII added or SDK only sends newly added PII if sendDefaultPII is enabled.
• I updated the docs if needed.
• I updated the wizard if needed.
• Review from the native team if needed.
• No breaking change or entry added to the changelog.
• No breaking change for hybrid SDKs or communicated to hybrid SDKs.

🔮 Next steps

• PR 7: Add Kafka to Spring Boot 3 OTel sample apps
• PR 8: OTel coexistence

⚠️ Merge this PR using a merge commit (not squash). Only the collection branch is squash-merged into main.

#skip-changelog

[github-actions]

Semver Impact of This PR

🟢 Patch (bug fixes)

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[sentry]

Sentry Build Distribution

App Name	App ID	Version	Configuration	Install Page
SDK Size	io.sentry.tests.size	8.37.1 (1)	release	Install Build

[github-actions]

Performance metrics 🚀

	Plain	With Sentry	Diff
Startup time	312.65 ms	367.12 ms	54.47 ms
Size	0 B	0 B	0 B

Baseline results on branch: feat/queue-instrumentation-autoconfig

Startup times

Revision	Plain	With Sentry	Diff
25629e3	325.13 ms	383.40 ms	58.27 ms

App size

Revision	Plain	With Sentry	Diff
25629e3	0 B	0 B	0 B

Previous results on branch: feat/queue-instrumentation-e2e

Startup times

Revision	Plain	With Sentry	Diff
766d2f5	356.70 ms	418.39 ms	61.69 ms
7e898af	367.28 ms	426.94 ms	59.66 ms

App size

Revision	Plain	With Sentry	Diff
766d2f5	0 B	0 B	0 B
7e898af	0 B	0 B	0 B