Dockerizing a Spring Boot Application Step-by-Step

Introduction:

Dockerizing your Spring Boot application allows you to encapsulate it along with its dependencies into a lightweight, portable container. In this tutorial, we’ll walk through the process of Dockerizing a Spring Boot application step-by-step. By the end, you’ll have a Docker container ready to deploy your Spring Boot application seamlessly.

Prerequisites:

• Basic understanding of Docker
• A Spring Boot application to Dockerize
• Docker installed on your system

Step 1: Create a Spring Boot Application:

If you haven’t already, create a Spring Boot application. You can use Spring Initializr or your preferred IDE to generate a new Spring Boot project.

Step 2: Dockerfile Creation:

Create a Dockerfile in the root directory of your Spring Boot project. This file contains instructions for Docker to build your application image.

# Use a base image with JDK
FROM openjdk:11-jre-slim

# Set the working directory inside the container
WORKDIR /app

# Copy the packaged JAR file into the container
COPY target/your-application.jar /app

# Expose the port your application runs on
EXPOSE 8080

# Command to run the application
CMD ["java", "-jar", "your-application.jar"]

Step 3: Build Docker Image:

Open a terminal window, navigate to your project directory, and run the following command to build your Docker image:

docker build -t your-image-name .

Replace your-image-name with a suitable name for your Docker image.

Step 4: Run Docker Container:

Once the image is built successfully, you can run a Docker container using the following command:

docker run -p 8080:8080 your-image-name

Replace your-image-name with the name you provided in the previous step.

Step 5: Test Your Application:

Open a web browser and navigate to http://localhost:8080 to see your Spring Boot application running inside a Docker container.

Conclusion:

Congratulations! You’ve successfully Dockerized your Spring Boot application. You can now deploy your containerized application to any environment that supports Docker, making it easier to manage and scale.