How to dockerize a spring boot application.
Docker is a tool that allows developers to easily deploy their applications in a containerized format, making it easy to run and manage applications in a variety of environments. In this article, we will discuss how to dockerize a Spring Boot application and run it in a Docker container.
To dockerize a Spring Boot application, you will need to create a Dockerfile that contains the instructions for building the Docker image. The Dockerfile should start by specifying the base image that your application will be built on top of. In this example, we will use the openjdk:8-jdk-alpine image as the base image.
FROM openjdk:11-jdk-alpine
Next, we will need to specify the directory where our application code will be copied to inside the Docker image. We will use the /app directory for this purpose.
RUN mkdir /appAfter that, we would need to copy our Spring boot application code into the /app directory.
COPY target/my-spring-boot-app.jar /app/
Finally, we will specify the command that will be used to run our Spring Boot application inside the Docker container. In this case, we will use the java command to run the application.
CMD ["java", "-jar", "/app/my-spring-boot-app.jar"]
Now that we have created the Dockerfile, we can build the Docker image by running the following command in the directory where the Dockerfile is located:
$ docker build -t my-spring-boot-app .
This will create a Docker image with the name my-spring-boot-app that contains our Spring Boot application.
To run the Docker image, we can use the docker run command:
$ docker run -p 8080:8080 my-spring-boot-app
This will run the Docker image and map port 8080 on the host machine to port 8080 inside the Docker container, allowing us to access the Spring Boot application on our local machine.
That’s it! You have successfully dockerized your Spring Boot application and run it in a Docker container. Docker makes it easy to package and deploy your applications, ensuring that they will run consistently in any environment.
