Dockerizing Spring Boot REST API Gradle

Gradle-based Spring Boot applications are dockerized in almost the same way as Maven projects.

The main difference is the build command and output location. Gradle usually creates the JAR inside build/libs.

Build the project

Run:

./gradlew clean build

On Windows, you may use:

gradlew.bat clean build

After the build, check:

build/libs/

You should see the application JAR.

Dockerfile

Create a Dockerfile:

FROM eclipse-temurin:17-jre
WORKDIR /app
COPY build/libs/*.jar app.jar
EXPOSE 8080
CMD ["java", "-jar", "app.jar"]

Using *.jar is convenient for beginner projects, but in production you may prefer the exact JAR name.

Build the Docker image

docker build -t spring-gradle-api:1.0 .

Run the API

docker run -d -p 8080:8080 --name gradle-api spring-gradle-api:1.0

Test an endpoint:

http://localhost:8080/api

Use the actual endpoint from your application.

Debug if needed

docker logs gradle-api
docker ps -a

If the container exits immediately, the Spring Boot app probably failed during startup.

Written By: Shiva Srivastava