Remove unavailable spring-boot-starter-restclient dependency

.dockerignore

@@ -0,0 +1,10 @@
+target
+.mvn
+.git
+.github
+.idea
+*.iml
+Dockerfile*
+node_modules
+build
+out

.github/workflows/ci-petclinic-eks.yaml

@@ -29,7 +29,7 @@ jobs:
         uses: actions/setup-java@v4
         with:
           distribution: temurin
-          java-version: "25"
+          java-version: "21"
           cache: maven
 
       - name: Maven build & test
@@ -61,7 +61,7 @@ jobs:
         uses: actions/setup-java@v4
         with:
           distribution: temurin
-          java-version: "25"
+          java-version: "21"
           cache: maven
 
       - name: Configure AWS credentials (OIDC)

.github/workflows/ci-petclinic-gke.yaml

@@ -31,7 +31,7 @@ jobs:
         uses: actions/setup-java@v4
         with:
           distribution: temurin
-          java-version: "25"
+          java-version: "21"
           cache: maven
 
       - name: Maven build & test
@@ -63,7 +63,7 @@ jobs:
         uses: actions/setup-java@v4
         with:
           distribution: temurin
-          java-version: "25"
+          java-version: "21"
           cache: maven
 
       - name: Authenticate to Google Cloud (WIF)

Dockerfile

@@ -1,9 +1,9 @@
 # syntax=docker/dockerfile:1.6
 
 ARG JAVA_VERSION=21
-ARG MAVEN_IMAGE=maven:3.9-eclipse-temurin-21
-ARG JDK_IMAGE=eclipse-temurin:21-jdk
-ARG DISTROLESS_IMAGE=gcr.io/distroless/base-debian12:nonroot
+ARG MAVEN_IMAGE=maven:3.9-eclipse-temurin-${JAVA_VERSION}
+ARG JDK_IMAGE=eclipse-temurin:${JAVA_VERSION}-jdk
+ARG RUNTIME_IMAGE=eclipse-temurin:${JAVA_VERSION}-jre
 
 # =========================
 # 1) Build
@@ -17,7 +17,7 @@ RUN --mount=type=cache,target=/root/.m2 \
 
 COPY . .
 RUN --mount=type=cache,target=/root/.m2 \
-    mvn -q -DskipTests package
+    mvn -q -DskipTests clean package
 
 RUN set -eux; \
     JAR="$(ls -1 target/*.jar | head -n 1)"; \
@@ -37,7 +37,6 @@ RUN set -eux; \
     mkdir -p /whatap; \
     tar -xzf /tmp/whatap.agent.java.tar.gz -C /whatap; \
     rm -f /tmp/whatap.agent.java.tar.gz; \
-    # agent jar 찾기
     AGENT_JAR="$(find /whatap -maxdepth 6 -type f \
       \( -name 'whatap.agent*.jar' -o -name '*whatap*agent*.jar' \) | head -n 1)"; \
     test -n "$AGENT_JAR"; \
@@ -46,48 +45,44 @@ RUN set -eux; \
     chmod -R a=rX /whatap
 
 # =========================
-# 3) jlink Slim JRE
+# 3) Runtime (fallback-first: temurin JRE)
 # =========================
-FROM ${JDK_IMAGE} AS jre
-WORKDIR /jrebuild
-
-COPY --from=builder /app/app.jar ./app.jar
-
-RUN set -eux; \
-    DEPS="$(jdeps --ignore-missing-deps --multi-release=21 --print-module-deps app.jar)"; \
-    jlink --strip-debug --no-man-pages --no-header-files --compress=2 \
-      --add-modules "$DEPS,\
-java.desktop,java.management,jdk.management,java.sql,java.naming,\
-java.logging,java.security.jgss,jdk.security.auth,java.security.sasl,java.instrument,\
-jdk.crypto.ec,jdk.unsupported,java.xml" \
-      --output /opt/jre
-
-# =========================
-# 4) Runtime (Distroless)
-# =========================
-FROM ${DISTROLESS_IMAGE}
+# 기본 목표는 “정상 기동”이므로 디버깅이 용이한 eclipse-temurin JRE를 사용한다.
+# distroless/jlink 최적화는 별도 커밋에서 재적용한다.
+FROM ${RUNTIME_IMAGE}
 WORKDIR /app
 
-COPY --from=jre     /opt/jre    /opt/jre
-COPY --from=builder /app/app.jar ./app.jar
+COPY --from=builder /app/app.jar /app/app.jar
+COPY --from=whatap_agent /whatap /whatap
 
-# ✅ 핵심: /whatap 을 nonroot(65532)가 소유하도록 복사
-COPY --from=whatap_agent --chown=65532:65532 /whatap /whatap
+ENV JAVA_TOOL_OPTIONS="" \
+    JAVA_OPTS="" \
+ENABLE_WHATAP=false \
+WHATAP_HOME=/whatap
 
-ENV JAVA_HOME=/opt/jre
-ENV PATH="/opt/jre/bin:${PATH}"
+# ENTRYPOINT wrapper: ENABLE_WHATAP=true 일 때만 agent 옵션을 추가한다.
+COPY <<'EOF' /entrypoint.sh
+#!/bin/sh
+set -eu
 
-# ✅ whatap home 명시(에이전트가 내부 파일 쓸 때 경로 확정)
-ENV WHATAP_HOME=/whatap
+JAVA_ARGS=${JAVA_OPTS:-}
+case "${ENABLE_WHATAP:-false}" in
+  true|TRUE|True)
+  JAVA_ARGS="$JAVA_ARGS -javaagent:/whatap/whatap.agent.jar"
+  JAVA_ARGS="$JAVA_ARGS -Dwhatap.paramkey=/whatap/paramkey.txt"
+  JAVA_ARGS="$JAVA_ARGS -Dwhatap.server.host=${WHATAP_SERVER_HOST:-}"
+  JAVA_ARGS="$JAVA_ARGS -Dlicense=${WHATAP_LICENSE:-}"
+  JAVA_ARGS="$JAVA_ARGS -Dwhatap.micro.enabled=${WHATAP_MICRO_ENABLED:-}"
+  JAVA_ARGS="$JAVA_ARGS --add-opens=java.base/java.lang=ALL-UNNAMED"
+  ;;
+esac
 
-ENV JAVA_TOOL_OPTIONS="\
--javaagent:/whatap/whatap.agent.jar \
--Dwhatap.paramkey=/whatap/paramkey.txt \
---add-opens=java.base/java.lang=ALL-UNNAMED \
--XX:+UseContainerSupport \
--XX:MaxRAMPercentage=75 \
--XX:+ExitOnOutOfMemoryError \
--XX:+AlwaysActAsServerClassMachine"
+exec java $JAVA_ARGS -XX:+UseContainerSupport -XX:MaxRAMPercentage=75 \
+  -XX:+ExitOnOutOfMemoryError -XX:+AlwaysActAsServerClassMachine \
+  -jar /app/app.jar
+EOF
+
+RUN chmod +x /entrypoint.sh
 
 EXPOSE 8080
-ENTRYPOINT ["/opt/jre/bin/java", "-jar", "/app/app.jar"]
+ENTRYPOINT ["/entrypoint.sh"]

README.md

@@ -110,3 +110,28 @@ CSP별 Ingress, Registry, Secret 차이로 매니페스트 분리
 
 본 프로젝트는 멀티클라우드 환경에서 GitOps 기반 CI/CD와  
 운영 분리를 어떻게 설계할 수 있는지를 보여주는 예제입니다.
+
+---
+
+## 9. Spring Boot 3.x 다운그레이드 메모 (Boot 4.0.0-M3 → Boot 3.2.5)
+
+- 참고 문서: *Spring Boot 3 Migration Guide*, *Spring Boot 3.2 Release Notes*, *Spring Framework 6.x*.
+- Jakarta 네임스페이스 전환 이후 API 의존성은 Boot 3.x 기본 BOM을 따라가며, Boot 4 / Spring 7 전용 의존성은 제거/하향 조정했다.
+- Java 21 런타임을 유지하며, 모듈 경계 문제를 피하기 위해 `--add-opens=java.base/java.lang=ALL-UNNAMED` 옵션을 Whatap 활성화 시에만 주입한다.
+- distroless/jlink 최적화는 별도 커밋으로 재적용 예정이며, 현재는 디버깅 및 호환성을 우선한 `eclipse-temurin:21-jre` 런타임을 사용한다.
+
+### 잠재 호환 이슈 및 대응
+- 서드파티 라이브러리의 Spring 7 전용 API 사용 → Boot 3.x BOM 기준으로 의존성 하향. 필요 시 BOM에 맞는 버전으로 재빌드.
+- 에이전트/모듈 경계(`--add-opens`) 누락 시 JVM 시작 실패 가능 → Whatap 활성화 경로에서만 옵션을 주입하고, 기본 OFF 모드로 기동 보장.
+- 컨테이너 디버깅(쉘 유무) → distroless 대신 temurin JRE를 기본값으로 사용, 추후 최적화는 별도 PR로 진행.
+
+---
+
+## 10. WhaTap APM 토글 사용법
+
+- 기본값: OFF (`ENABLE_WHATAP=false`).
+- 활성화: 컨테이너/Deployment 환경 변수로 아래를 설정한다.
+  - `ENABLE_WHATAP=true`
+  - `WHATAP_LICENSE`, `WHATAP_SERVER_HOST`, `WHATAP_MICRO_ENABLED`
+- 이미지에 `/whatap/whatap.agent.jar`, `/whatap/paramkey.txt`가 포함되어 있으며, 활성화 시 엔트리포인트 래퍼가 자동으로 JVM 옵션을 주입한다.
+- 외부 Secret(ExternalSecret: `whatap-apm-secret`)은 라이선스/서버/마이크로 트레이싱 키만 제공하며, `paramkey.txt`는 이미지에 포함된 파일을 사용한다.

build.gradle

@@ -1,7 +1,7 @@
 plugins {
   id 'java'
   id 'checkstyle'
-  id 'org.springframework.boot' version '4.0.0-M3'
+  id 'org.springframework.boot' version '3.2.5'
   id 'io.spring.dependency-management' version '1.1.7'
   id 'org.graalvm.buildtools.native' version '0.11.1'
   id 'org.cyclonedx.bom' version '3.0.0'
@@ -13,11 +13,11 @@ plugins {
 gradle.startParameter.excludedTaskNames += [ "checkFormatAot", "checkFormatAotTest" ]
 
 group = 'org.springframework.samples'
-version = '4.0.0-SNAPSHOT'
+version = '3.2.5-SNAPSHOT'
 
 java {
   toolchain {
-    languageVersion = JavaLanguageVersion.of(25)
+    languageVersion = JavaLanguageVersion.of(21)
   }
 }
 
@@ -77,7 +77,7 @@ checkstyleNohttp {
 }
 
 tasks.withType(JavaCompile).configureEach {
-  options.release = 17
+  options.release = 21
   options.errorprone {
     disableAllChecks = true
   }

k8s/aws/20-petclinic-Deployments-postgre.yaml

@@ -37,17 +37,15 @@ spec:
             - name: SPRING_DATASOURCE_DRIVER_CLASS_NAME
               value: "org.postgresql.Driver"
             - name: APP_VERSION
-              value: "A-4.0.0-49c6082"
+              value: "A-3.2.x"
             - name: NODE_IP
               valueFrom: {fieldRef: {fieldPath: status.hostIP}}
             - name: NODE_NAME
               valueFrom: {fieldRef: {fieldPath: spec.nodeName}}
             - name: POD_NAME
               valueFrom: {fieldRef: {fieldPath: metadata.name}}
-            # ✅ Whatap + 기존 JVM 옵션 (덮어쓰기 주의 OK)
-            - name: JAVA_TOOL_OPTIONS
-              value: >-
-                -javaagent:/whatap/whatap.agent.jar -Dwhatap.server.host=$(WHATAP_SERVER_HOST) -Dlicense=$(WHATAP_LICENSE) -Dwhatap.micro.enabled=$(WHATAP_MICRO_ENABLED) -Dwhatap.paramkey=/whatap/paramkey.txt -XX:+UseContainerSupport -XX:MaxRAMPercentage=75 -XX:+ExitOnOutOfMemoryError -XX:+AlwaysActAsServerClassMachine
+            - name: ENABLE_WHATAP
+              value: "false"
           ports:
             - name: http
               containerPort: 8080

k8s/gcp/10-petclinic-secret-whatap.yaml

@@ -0,0 +1,26 @@
+apiVersion: external-secrets.io/v1
+kind: ExternalSecret
+metadata:
+  name: whatap-apm-secret
+  namespace: petclinic-ns
+spec:
+  refreshInterval: 1h
+  secretStoreRef:
+    name: gcp-secretmanager
+    kind: ClusterSecretStore
+  target:
+    name: whatap-apm-secret
+    creationPolicy: Owner
+  data:
+    - secretKey: WHATAP_LICENSE
+      remoteRef:
+        key: finalproj-dev-whatap-apm
+        property: license
+    - secretKey: WHATAP_SERVER_HOST
+      remoteRef:
+        key: finalproj-dev-whatap-apm
+        property: server_host
+    - secretKey: WHATAP_MICRO_ENABLED
+      remoteRef:
+        key: finalproj-dev-whatap-apm
+        property: micro_enabled

k8s/gcp/20-petclinic-Deployments-postgre.yaml

@@ -35,6 +35,8 @@ spec:
           envFrom:
             - secretRef:
                 name: petclinic-db-secret
+            - secretRef:
+                name: whatap-apm-secret
 
           # 🔹 여기: Spring profile을 postgres용으로
           env:
@@ -48,7 +50,9 @@ spec:
             - name: SPRING_JPA_HIBERNATE_DDL_AUTO
               value: "none"
             - name: APP_VERSION
-              value: "local"
+              value: "A-3.2.x"
+            - name: ENABLE_WHATAP
+              value: "false"
               
           ports:
             - name: http

pom.xml

@@ -5,13 +5,13 @@
   <parent>
     <groupId>org.springframework.boot</groupId>
     <artifactId>spring-boot-starter-parent</artifactId>
-    <version>4.0.0-M3</version>
+    <version>3.2.5</version>
     <relativePath></relativePath>
   </parent>
 
   <groupId>org.springframework.samples</groupId>
   <artifactId>spring-petclinic</artifactId>
-  <version>4.0.0-SNAPSHOT</version>
+  <version>3.2.5-SNAPSHOT</version>
 
   <name>petclinic</name>
 
@@ -72,11 +72,6 @@
       <artifactId>spring-boot-starter-test</artifactId>
       <scope>test</scope>
     </dependency>
-    <dependency>
-      <groupId>org.springframework.boot</groupId>
-      <artifactId>spring-boot-starter-restclient</artifactId>
-      <scope>test</scope>
-    </dependency>
 
     <!-- Databases - Uses H2 by default -->
     <dependency>
@@ -316,6 +311,7 @@
         <?m2e ignore?>
         <groupId>org.cyclonedx</groupId>
         <artifactId>cyclonedx-maven-plugin</artifactId>
+        <version>2.9.1</version>
       </plugin>
 
     </plugins>