迁移至Java 11 Runtime后Google App Engine部署失败求助

问题背景 #

原Java 8环境下正常部署的Ktor项目，迁移到Java 11 Runtime后部署报错。已完成以下配置变更：

• 替换appengine-web.xml/web.xml为app.yaml
• 配置JAVA_HOME指向Java 11
• 更新build.gradle的sourceCompatibility和targetCompatibility为11

关键配置 #

app.yaml

runtime: java11
entrypoint: 'ProjectName-1.0-SNAPSHOT.jar'
instance_class: F1
automatic_scaling:
  max_pending_latency: 500ms
  min_idle_instances: 1
  max_idle_instances: 1
  max_concurrent_requests: 80
  min_instances: 1
  max_instances: 1
  target_cpu_utilization: 0.95
  target_throughput_utilization: 0.95

build.gradle

sourceCompatibility = 11    
targetCompatibility = 11 

报错日志 #

Starting Step #2 - "build"
Step #2 - "build": Already have image (with digest): asia.gcr.io/gae-runtimes/buildpacks/google-gae-18/java/builder:java_20231016_RC00
Step #2 - "build": ===> ANALYZING
Step #2 - "build": ERROR: failed to initialize analyzer: getting previous image: getting config file for image "asia.gcr.io/projectName/app-engine-tmp/app/default/ttl-18h:latest": GET https://storage.googleapis.com/asia.artifacts.prjectname.appspot.com/containers/images/sha256:{theHashCodeHere}?access_token=REDACTED: unexpected status code 404 Not Found: <?xml version='1.0' encoding='UTF-8'?><Error><Code>NoSuchKey</Code><Message>The specified key does not exist.</Message><Details>No such object: asia.artifacts.projectname.appspot.com/containers/images/sha256:{theHashCodeHere}</Details></Error>
Finished Step #2 - "build"
ERROR
ERROR: build step 2 "asia.gcr.io/gae-runtimes/buildpacks/google-gae-18/java/builder:java_20231016_RC00" failed: step exited with non-zero status: 1

解决方法 #

1. 强制跳过构建缓存 #

报错核心是buildpack尝试复用已不存在的旧构建镜像，执行部署命令时添加--no-cache参数强制从头构建：

gcloud app deploy --no-cache

2. 修正entrypoint启动命令 #

Java 11 Runtime要求明确指定Java启动命令，不能直接写Jar文件名，修改app.yaml的entrypoint：

entrypoint: 'java -jar ProjectName-1.0-SNAPSHOT.jar'

若Jar文件在子目录（如build/libs），需补充完整相对路径：

entrypoint: 'java -jar build/libs/ProjectName-1.0-SNAPSHOT.jar'

3. 检查Artifact Registry权限 #

确保部署账号拥有roles/artifactregistry.writer或更高权限，同时确认项目的Artifact Registry仓库（asia.artifacts.projectname.appspot.com）已存在（GAE通常自动创建，若缺失可手动创建）。

4. 更新gcloud CLI到最新版本 #

旧版本CLI可能与Java 11 Runtime的buildpack存在兼容性问题，执行更新：

gcloud components update

内容的提问来源于stack exchange，提问作者Anudeep Ananth