Dockerfile for Java Spring boot project

Docker-slim

# our base build image
FROM maven:3.6-jdk-8-alpine as maven

# copy the project files
COPY ./pom.xml ./pom.xml

# build all dependencies
RUN mvn dependency:go-offline -B

# copy your other files
COPY ./src ./src

# build for release
RUN mvn package

# our final base image
FROM openjdk:8-jre-alpine

# set deployment directory
WORKDIR /workspace

# copy over the built artifact from the maven image
COPY --from=maven target/testing-framework-be*.jar ./app.jar

EXPOSE 8080

CMD ["java", "-jar", "app.jar"]

Dockerfile

# Our base build image
FROM maven:3-jdk-8-alpine as builder

LABEL maintainer  DUC NGUYEN <[email protected]>

WORKDIR /workspace/app

COPY pom.xml .

RUN mvn dependency:go-offline -B

COPY src src

RUN mvn clean package
RUN mkdir -p target/dependency && (cd target/dependency; jar -xf ../*.jar)

# Our final base image
FROM openjdk:8-jre-alpine

ARG DEPENDENCY=/workspace/app/target/dependency
ARG APP_CLASS="your.package.example.Application"

COPY --from=builder ${DEPENDENCY}/BOOT-INF/lib /app/lib
COPY --from=builder ${DEPENDENCY}/META-INF /app/META-INF
COPY --from=builder ${DEPENDENCY}/BOOT-INF/classes /app

EXPOSE 8080

ENTRYPOINT ["java","-cp","app:app/lib/*", ${APP_CLASS}]

docker build -t some-tags .

• Maven will download the world on first build ( slow )
• Change java code , rerun build command -> code will rebuild ( fast )
• Change pom.xml file , Maven will download the whole-world again :sad_dog: ( slow )