本節介紹如何使用 GraalVM 的本機映像產生器從 Spring Boot 應用程式建立本機映像，以及如何在 Docker 容器中執行此本機映像。
在軟體架構和微服務架構設計中，我們必須考慮應用程式的可擴展性、效能。每當應用程式中的請求數量增加時，我們的應用程式應該開始快速擴展並有效地利用資源。
我正在考慮使用 Spring Boot 提前 (AOT) 編譯與 GraalVM 以及 Java 虛擬線程（在 JDK 21 及更高版本中可用）在容器中運行可執行檔。
在這個架構設計決策中，我們獲得了好處，但也必須考慮以下實施挑戰和設計注意事項：
Spring Boot 應用
為了測試這個用例，我正在建立一個 Spring Boot 應用程序，該應用程式在「/hello」處公開 REST 端點。我正在使用以下配置、庫和工具：
我們需要在 POM XML 檔案中新增以下配置。
Spring Boot 屬性配置
<properties>
<java.version>22</java.version>
<spring-native.version>0.12.1</spring-native.version>
</properties>
Spring Boot AOT 外掛程式配置
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<executions>
<execution>
<id>process-aot</id>
<goals>
<goal>process-aot</goal>
</goals>
</execution>
</executions>
</plugin>
GraalVM 外掛程式配置
<plugin>
<groupId>org.graalvm.buildtools</groupId>
<artifactId>native-maven-plugin</artifactId>
<configuration>
<imageName>app-native-binary</imageName>
<metadataRepository>
<enabled>true</enabled>
</metadataRepository>
<buildArgs>
<buildArg>--static --libc=musl</buildArg>
<buildArg>-H:+ReportExceptionStackTraces</buildArg>
</buildArgs>
<mainClass>com.developerhelperhub.tutorial.springboot.tutorial.TutorialStartupPerformanceApplication</mainClass>
</configuration>
<executions>
<execution>
<id>add-reachability-metadata</id>
<goals>
<goal>add-reachability-metadata</goal>
</goals>
</execution>
</executions>
</plugin>
我們需要為特定作業系統主機和 CPU 架構建立本機映像，本機映像將在容器中運作。
我們使用 Alpine Linux 來在容器中運行我們的應用程序，因為它體積小、簡單且安全。為了實現這一點，我們需要使用適當的 GraalVM 配置來建立我們的應用程式。 Alpine 的系統需求是作業系統和 CPU 架構。
以下指令我們可以用來檢查「amd64/alpine」影像
docker pull amd64/alpine # pull the image docker image inspect amd64/alpine # inspect the image
We can use docker container to build the native image instead of setup the GraalVM and Java related configuration in our locally. I am using “ghcr.io/graalvm/native-image-community:22-muslib” docker image to build the native.
Following command we can use to inspect the “ghcr.io/graalvm/native-image-community:22-muslib” image
docker pull ghcr.io/graalvm/native-image-community:22-muslib # pull the image docker image inspect ghcr.io/graalvm/native-image-community:22-muslib # inspect the image
I am creating a build image to test and debug the container, ensuring that all configurations and services are installed correctly. This approach will help us quickly identify and resolve any issues.
Following steps are added in the docker file, the file name “DockerfileBuild”
FROM ghcr.io/graalvm/native-image-community:22-muslib as build # Install necessary tools RUN microdnf install wget RUN microdnf install xz # Install maven for build the spring boot application RUN wget https://dlcdn.apache.org/maven/maven-3/3.9.8/binaries/apache-maven-3.9.8-bin.tar.gz RUN tar xvf apache-maven-3.9.8-bin.tar.gz # Set up the environment variables needed to run the Maven command. ENV M2_HOME=/app/apache-maven-3.9.8 ENV M2=$M2_HOME/bin ENV PATH=$M2:$PATH # Install UPX (Ultimate Packer for eXecutables) to compress the executable binary and reduce its size. RUN wget https://github.com/upx/upx/releases/download/v4.2.4/upx-4.2.4-amd64_linux.tar.xz RUN tar xvf upx-4.2.4-amd64_linux.tar.xz # Set up the environment variables required to run the UPX command. ENV UPX_HOME=/app/upx-4.2.4-amd64_linux ENV PATH=$UPX_HOME:$PATH #Copy the spring boot source code into container RUN mkdir -p /app/spring-boot-rest-api-app COPY spring-boot-rest-api-app /app/spring-boot-rest-api-app #Compile the native image RUN cd /app/spring-boot-rest-api-app && mvn -Pnative native:compile #Compressed binary file RUN upx -7 -k /app/spring-boot-rest-api-app/target/app-native-binary WORKDIR /app ENTRYPOINT ["/bin/bash"]
I am using the UPX compression tool in the build process to reduce the image size, UPX will typically reduce the file size of programs and DLLs by around 50%-70%, thus reducing disk space, network load times, download times and other distribution and storage costs.
Use the following command to build the Docker image.
docker build --no-cache -f DockerfileBuild -t alpine-graalvm-build .
After the build is complete, the image size will be 1.85 GB.
REPOSITORY TAG IMAGE ID CREATED SIZE alpine-graalvm-build latest 81d23bc1bc99 36 seconds ago 1.85GB
We can verify the configuration and installation within the container before creating a smaller container inside the Alpine Linux box. The following command will allow us to enter the container:
docker run --rm -it --entrypoint /bin/bash alpine-graalvm-build java --version #verify the java version mvn --version #verify the maven version upx --version #verify the upx version ls /app/spring-boot-rest-api-app/target/app-native-binary #verify the binary available /app/spring-boot-rest-api-app/target/app-native-binary #run the executable
We know that this native image includes all the dependencies necessary to run the binary standalone, without requiring any build-related tools such as GraalVM, Maven, UPX, or source code. We can use a Docker multi-stage build approach to copy the build file into our application image. By using multiple stages, you can separate the build environment from the runtime environment. This means only the necessary artifacts are included in the final image, significantly reducing its size.
Following steps are added in the docker file, the file name “DockerfileBuildAndCreateAlpineContainer”
FROM ghcr.io/graalvm/native-image-community:22-muslib as build # Install necessary tools RUN microdnf install wget RUN microdnf install xz # Install maven for build the spring boot application RUN wget https://dlcdn.apache.org/maven/maven-3/3.9.8/binaries/apache-maven-3.9.8-bin.tar.gz RUN tar xvf apache-maven-3.9.8-bin.tar.gz # Set up the environment variables needed to run the Maven command. ENV M2_HOME=/app/apache-maven-3.9.8 ENV M2=$M2_HOME/bin ENV PATH=$M2:$PATH # Install UPX (Ultimate Packer for eXecutables) to compress the executable binary and reduce its size. RUN wget https://github.com/upx/upx/releases/download/v4.2.4/upx-4.2.4-amd64_linux.tar.xz RUN tar xvf upx-4.2.4-amd64_linux.tar.xz # Set up the environment variables required to run the UPX command. ENV UPX_HOME=/app/upx-4.2.4-amd64_linux ENV PATH=$UPX_HOME:$PATH #Copy the spring boot source code into container RUN mkdir -p /app/spring-boot-rest-api-app COPY spring-boot-rest-api-app /app/spring-boot-rest-api-app #Compile the native image RUN cd /app/spring-boot-rest-api-app && mvn -Pnative native:compile #Compressed binary file RUN upx -7 -k /app/spring-boot-rest-api-app/target/app-native-binary WORKDIR /app #Second stage: Create the runtime image FROM amd64/alpine #Set the working directory WORKDIR /app #Copy the built application from the first stage COPY --from=build /app/spring-boot-rest-api-app/target/app-native-binary . #Expose port which our spring boot application is running EXPOSE 8080 #Command to run the application ENTRYPOINT ["/app/app-native-binary"]
Use the following command to build the Docker image.
docker build -f DockerfileBuildAndCreateAlpineContainer -t alpine-graalvm .
After the build is complete, the image size of container will be 32.8MB.
REPOSITORY TAG IMAGE ID CREATED SIZE alpine-graalvm latest 79676c696920 11 seconds ago 32.8MB
We can verify the container.
docker run --rm -it --entrypoint sh alpine-graalvm ls /app #verify the binary available /app/app-native-binary #run the executable
The application startup time is just 0.074 seconds, whereas a typical Spring Boot application running on the JVM has a startup time of approximately 1.665 seconds.
Started TutorialStartupPerformanceApplication in 0.074 seconds (process running for 0.075)
Following command can be use to run the docker container for running the application
docker run -d --name test-app -p 8080:8080 alpine-graalvm #run the container curl http://localhost:8080/hello # checking the endpoints
以上是使用 GraalVM 建構器從 Spring Boot 應用程式建立本機映像的詳細內容。更多資訊請關注PHP中文網其他相關文章！
