Creating a Docker image for a Spring Boot application allows you to containerize your app, making it easier to run in various environments without worrying about dependencies. In this blog, I’ll guide you through creating a Docker image for a Spring Boot app using the spt-development-demo project as a reference.

Steps to Create a Docker Image for Spring Boot Application

1. Clone the Demo Project

First, clone the spt-development-demo project from GitHub:

2. Build the Application with Spring Boot’s Built-in Docker Support

Spring Boot’s build-image goal uses Cloud Native Buildpacks to package the application into a Docker image without needing a Dockerfile. Simply run the following command:

This command builds the Docker image with the tag spt-development-demo using the JAR created by Spring Boot.

3. Run the Docker Container

Once the image is built, run it using Docker. Map port 8080 on your local machine to port 8080 in the container:

After running this command, your Spring Boot application will be accessible at http://localhost:8080.

Optional: Push the Docker Image to a Registry

If you want to share your Docker image, you can tag and push it to Docker Hub (or another container registry):

  1. Tag the image with your Docker Hub username:
  1. Push the image to Docker Hub:

Conclusion

Using Spring Boot’s built-in build-image support simplifies the Docker build process. With just a single Maven command, you can package your Spring Boot application as a Docker image without a Dockerfile. The spt-development-demo project demonstrates this easy method, making it a great choice for deploying Spring Boot apps in Docker.

Happy containerizing!