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Merged
igorcampos-dev merged 1 commit into from
Jul 21, 2025
Merged

chore(spring-kafka-example): add Docker support and split application… #13

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62 changes: 62 additions & 0 deletions spring-kafka-example/.dockerignore
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# Include any files or directories that you don't want to be copied to your
# container here (e.g., local build artifacts, temporary files, etc.).
#
# For more help, visit the .dockerignore file reference guide at
# https://docs.docker.com/go/build-context-dockerignore/

**/.DS_Store
**/.classpath
**/.dockerignore
**/.env
**/.factorypath
**/.git
**/.gitignore
**/.idea
**/.project
**/.sts4-cache
**/.settings
**/.toolstarget
**/.vs
**/.vscode
**/.next
**/.cache
**/*.dbmdl
**/*.jfm
**/charts
**/docker-compose*
**/compose.y*ml
**/Dockerfile*
**/secrets.dev.yaml
**/values.dev.yaml
**/vendor
LICENSE
README.md
**/*.class
**/*.iml
**/*.ipr
**/*.iws
**/*.log
**/.apt_generated
**/.gradle
**/.gradletasknamecache
**/.nb-gradle
**/.springBeans
**/build
**/dist
**/gradle-app.setting
**/nbbuild
**/nbdist
**/nbproject/private
**/target
*.ctxt
.mtj.tmp
.mvn/timing.properties
buildNumber.properties
dependency-reduced-pom.xml
hs_err_pid*
pom.xml.next
pom.xml.releaseBackup
pom.xml.tag
pom.xml.versionsBackup
release.properties
replay_pid*
47 changes: 47 additions & 0 deletions spring-kafka-example/Dockerfile
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FROM eclipse-temurin:21-jdk-jammy as deps

WORKDIR /build

COPY --chmod=0755 mvnw mvnw
COPY .mvn/ .mvn/

RUN --mount=type=bind,source=pom.xml,target=pom.xml \
--mount=type=cache,target=/root/.m2 ./mvnw dependency:go-offline -DskipTests

FROM deps as package

WORKDIR /build

COPY ./src src/
RUN --mount=type=bind,source=pom.xml,target=pom.xml \
--mount=type=cache,target=/root/.m2 \
./mvnw package -DskipTests && \
mv target/$(./mvnw help:evaluate -Dexpression=project.artifactId -q -DforceStdout)-$(./mvnw help:evaluate -Dexpression=project.version -q -DforceStdout).jar target/app.jar

FROM package as extract

WORKDIR /build

RUN java -Djarmode=layertools -jar target/app.jar extract --destination target/extracted

FROM eclipse-temurin:21-jre-jammy AS final

ARG UID=10001
RUN adduser \
--disabled-password \
--gecos "" \
--home "/nonexistent" \
--shell "/sbin/nologin" \
--no-create-home \
--uid "${UID}" \
appuser
USER appuser

COPY --from=extract build/target/extracted/dependencies/ ./
COPY --from=extract build/target/extracted/spring-boot-loader/ ./
COPY --from=extract build/target/extracted/snapshot-dependencies/ ./
COPY --from=extract build/target/extracted/application/ ./

EXPOSE 80

ENTRYPOINT [ "java", "org.springframework.boot.loader.launch.JarLauncher" ]
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10 changes: 10 additions & 0 deletions spring-kafka-example/compose.yaml
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services:
server:
build:
context: .
ports:
- "80:80"
environment:
SERVER_PORT: "80"
SPRING_PROFILES_ACTIVE: "default"
Comment on lines +6 to +9
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@coderabbitai coderabbitai Bot Jul 21, 2025 •
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⚠️ Potential issue

Non-root image cannot bind to port 80
Your Dockerfile switches to appuser (UID 10001). Binding to privileged ports (<1024) will fail without CAP_NET_BIND_SERVICE. Either:

  1. Expose/bind an unprivileged port (e.g. 8080) inside the container and keep host port 80, or
  2. Grant the extra capability.

Most teams adopt option 1 for least-privilege.

-      - "80:80"
+      - "80:8080"
 ...
-      SERVER_PORT: "80"
+      SERVER_PORT: "8080"
📝 Committable suggestion

‼️ IMPORTANT
Carefully review the code before committing. Ensure that it accurately replaces the highlighted code, contains no missing lines, and has no issues with indentation. Thoroughly test & benchmark the code to ensure it meets the requirements.

Suggested change
- "80:80"
environment:
SERVER_PORT: "80"
SPRING_PROFILES_ACTIVE: "default"
- "80:8080"
environment:
SERVER_PORT: "8080"
SPRING_PROFILES_ACTIVE: "default"
🤖 Prompt for AI Agents 
In spring-kafka-example/compose.yaml around lines 6 to 9, the container is set
to bind the application to port 80, which is a privileged port and cannot be
bound by a non-root user (appuser with UID 10001). To fix this, change the
SERVER_PORT environment variable to an unprivileged port like 8080 and update
the port mapping to bind host port 80 to container port 8080 (e.g., "80:8080").
This avoids requiring extra capabilities and follows least-privilege best
practices.

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@igorcampos-dev igorcampos-dev Jul 21, 2025

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using port 80 in docker does not cause issues

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@coderabbitai coderabbitai Bot Jul 21, 2025

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@igorcampos-dev Thank you for the clarification! I appreciate you sharing your experience with this configuration. If it's working in your environment without issues, then that's what matters most for your setup.

✏️ Learnings added 
Learnt from: igorcampos-dev
PR: igorcampos-dev/spring-integrations-examples#13
File: spring-kafka-example/compose.yaml:6-9
Timestamp: 2025-07-21T00:47:12.429Z
Learning: In Docker containers, binding to port 80 with a non-root user may work in certain configurations or environments, despite port 80 being a privileged port. The user igorcampos-dev has confirmed that using port 80 in their Docker setup does not cause issues.

Note: Learnings are effective only in the context of similar code segments. To apply general coding guidelines, please configure review instructions. You can manage existing learnings in the app.


9 changes: 9 additions & 0 deletions spring-kafka-example/src/main/resources/application-dev.yml
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spring:

application:
name: spring-kafka-example-dev

logging:

pattern:
console: "%d{yyyy-MM-dd'T'HH:mm:ss} | ${spring.application.name} | %class{30} | %level | %m%n"
2 changes: 1 addition & 1 deletion spring-kafka-example/src/main/resources/application.yml
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spring:

application:
name: spring-kafka-example
name: spring-kafka-example-prd

logging:

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