Build a Docker image using Jib

Category : Kubernetes | Sub Category : Kubernetes With Java | By Prasad Bonam Last updated: 2023-11-21 10:40:05 Viewed : 219

Jib is a tool that simplifies the process of building Docker images for Java applications. Unlike traditional Docker builds, Jib builds and optimizes Docker images directly from your Java build tool without requiring a Docker daemon. Jib is commonly used with Maven or Gradle.

Here, will provide an example of using Jib with Maven to build a Docker image for a Spring Boot application.

1. Add Jib Plugin to Your Maven Project:

   Open your pom.xml file and add the Jib Maven Plugin configuration. Here is a minimal example:

   xmlCopy code
   <project>
       <!-- ... -->
       <build>
           <plugins>
               <plugin>
                   <groupId>com.google.cloud.tools</groupId>
                   <artifactId>jib-maven-plugin</artifactId>
                   <version>3.2.0</version>
                   <configuration>
                       <from>
                           <image>adoptopenjdk:11-jre-hotspot</image>
                       </from>
                       <to>
                           <image>your-image-name:tag</image>
                       </to>
                   </configuration>
               </plugin>
           </plugins>
       </build>
       <!-- ... -->
   </project>
   

   
   

   Replace your-image-name:tag with the desired name and tag for your Docker image.

2. The <plugin> configuration block you provided is part of the Maven build configuration in your pom.xml file. It specifies the configuration for the Jib Maven Plugin, which is responsible for building and pushing Docker images for your Java application

   • <groupId>, <artifactId>, and <version>: These elements identify the Jib Maven Plugin and specify its version. These details are essential to include the correct version of the plugin in your Maven build.

   • <configuration>: This block contains configuration settings specific to the Jib Maven Plugin.

     • <from>: Specifies the base image from which to build your application image. In this case, it uses the adoptopenjdk:11-jre-hotspot image, which is a popular base image for Java applications based on the AdoptOpenJDK distribution.

     • <to>: Specifies the target image to which your application image will be pushed. In this case, replace your-image-name:tag with the desired name and tag for your Docker image. This is the image name and version you will use when referring to your built Docker image.

   The Jib Maven Plugin simplifies the Docker image creation process by allowing you to configure the image settings directly in your Maven build file without the need for a Dockerfile. When you run mvn clean compile jib:build, Maven uses the Jib plugin to build and push your Docker image based on the provided configuration. The configuration you provided ensures that your application is built on top of the specified base image and pushed to the specified target image.

   
   

3. Build the Docker Image with Jib:

   Execute the following Maven command to build and push the Docker image:

   bashCopy code
   mvn clean compile jib:build
   

   This command tells Maven to use the Jib plugin to build and push the Docker image based on the configuration provided in the pom.xml.

4. Run the Docker Container:

   Once the image is built, you can run a container:

   bashCopy code
   docker run -p 8080:8080 your-image-name:tag
   

   Replace your-image-name:tag with the actual image name and tag you specified in the pom.xml.

Using Jib simplifies the Docker image build process, and you don`t need to manually write a Dockerfile. Jib automatically handles the containerization of your Java application, making it a convenient choice for Java developers. Note that Jib uses a layering strategy, so only changed parts of your application are rebuilt and pushed, reducing the image build time and size.