feat(samples): [Queue Instrumentation 2] Add Kafka to Spring Boot 3 sample app

[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 Kafka producer and consumer to the Spring Boot 3 (Jakarta) sample app behind a kafka Spring profile. This provides a manual test harness for upcoming Kafka queue instrumentation.

What's included:

• spring-kafka dependency (version catalog entry + sample app)
• KafkaController — REST endpoint at /kafka/produce that sends messages via KafkaTemplate
• KafkaConsumer — @KafkaListener that receives and logs messages from sentry-topic
• application-kafka.properties — Kafka config activated with --spring.profiles.active=kafka
• Kafka auto-configuration excluded by default so the sample app works without a Kafka broker

💡 Motivation and Context

PR 3–5 in this stack will add Kafka queue instrumentation (producer spans, consumer spans, auto-configuration). This sample app serves as the test harness to manually verify instrumentation works end-to-end before system tests are added in PR 6.

The Kafka components are gated behind a Spring profile so they don't affect existing sample app usage.

💚 How did you test it?

Sample app code — will be tested manually with a local Kafka broker when instrumentation is added.

📝 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 3: Kafka producer instrumentation (SentryKafkaTemplateWrapper)
• PR 4: Kafka consumer instrumentation (SentryKafkaRecordInterceptor)
• PR 5: Spring Boot 3 auto-configuration

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

#skip-changelog

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Semver Impact of This PR

🟡 Minor (new features)

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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

[cursor]

Cursor Bugbot has reviewed your changes and found 1 potential issue.

Bugbot Autofix prepared a fix for the issue found in the latest run.

• ✅ Fixed: Blanket clearing of all auto-configuration exclusions in kafka profile
  • Removed the empty profile override and added a kafka-profile configuration importing KafkaAutoConfiguration so only Kafka is re-enabled without wiping other exclusions.

Or push these changes by commenting:

@cursor push 2a59cecce2

Preview (2a59cecce2)

diff --git a/sentry-samples/sentry-samples-spring-boot-jakarta/src/main/java/io/sentry/samples/spring/boot/jakarta/KafkaProfileConfiguration.java b/sentry-samples/sentry-samples-spring-boot-jakarta/src/main/java/io/sentry/samples/spring/boot/jakarta/KafkaProfileConfiguration.java
new file mode 100644
--- /dev/null
+++ b/sentry-samples/sentry-samples-spring-boot-jakarta/src/main/java/io/sentry/samples/spring/boot/jakarta/KafkaProfileConfiguration.java
@@ -1,0 +1,11 @@
+package io.sentry.samples.spring.boot.jakarta;
+
+import org.springframework.boot.autoconfigure.kafka.KafkaAutoConfiguration;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.context.annotation.Import;
+import org.springframework.context.annotation.Profile;
+
+@Configuration
+@Profile("kafka")
+@Import(KafkaAutoConfiguration.class)
+public class KafkaProfileConfiguration {}

diff --git a/sentry-samples/sentry-samples-spring-boot-jakarta/src/main/resources/application-kafka.properties b/sentry-samples/sentry-samples-spring-boot-jakarta/src/main/resources/application-kafka.properties
--- a/sentry-samples/sentry-samples-spring-boot-jakarta/src/main/resources/application-kafka.properties
+++ b/sentry-samples/sentry-samples-spring-boot-jakarta/src/main/resources/application-kafka.properties
@@ -1,5 +1,4 @@
 # Kafka — activate with: --spring.profiles.active=kafka
-spring.autoconfigure.exclude=
 spring.kafka.bootstrap-servers=localhost:9092
 spring.kafka.consumer.group-id=sentry-sample-group
 spring.kafka.consumer.auto-offset-reset=earliest

_{This Bugbot Autofix run was free. To enable autofix for future PRs, go to the Cursor dashboard.}

[cursor]

Blanket clearing of all auto-configuration exclusions in kafka profile

Low Severity

Setting spring.autoconfigure.exclude= (empty) in application-kafka.properties blanket-clears all auto-configuration exclusions, not just the Kafka one. Spring Boot profile-specific properties fully replace (not merge with) base properties. If any other auto-configuration exclusion is later added to application.properties, activating the kafka profile would silently remove that exclusion too. A safer approach would be to use @Import(KafkaAutoConfiguration.class) on a @Profile("kafka") configuration class to surgically re-enable only the Kafka auto-config.

Additional Locations (1)

• sentry-samples/sentry-samples-spring-boot-jakarta/src/main/resources/application.properties#L41-L42