Dockerfile Examples

Docker commands

• docker build -t in28min/hello-world-docker:v1 .

Dockerfile - 1 - Creating Docker Images

FROM openjdk:18.0-slim
COPY target/*.jar app.jar
EXPOSE 5000
ENTRYPOINT ["java","-jar","/app.jar"]

Dockerfile - 2 - Build Jar File - Multi Stage

FROM maven:3.8.6-openjdk-18-slim AS build
WORKDIR /home/app
COPY . /home/app
RUN mvn -f /home/app/pom.xml clean package

FROM openjdk:18.0-slim
EXPOSE 5000
COPY --from=build /home/app/target/*.jar app.jar
ENTRYPOINT [ "sh", "-c", "java -jar /app.jar" ]

Dockerfile - 3 - Caching

FROM maven:3.8.6-openjdk-18-slim AS build
WORKDIR /home/app

COPY ./pom.xml /home/app/pom.xml
COPY ./src/main/java/com/in28minutes/rest/webservices/restfulwebservices/RestfulWebServicesApplication.java	/home/app/src/main/java/com/in28minutes/rest/webservices/restfulwebservices/RestfulWebServicesApplication.java

RUN mvn -f /home/app/pom.xml clean package

COPY . /home/app
RUN mvn -f /home/app/pom.xml clean package

FROM openjdk:18.0-slim
EXPOSE 5000
COPY --from=build /home/app/target/*.jar app.jar
ENTRYPOINT [ "sh", "-c", "java -jar /app.jar" ]

No Dockerfile - Maven Commands

mvn spring-boot:repackage
mvn spring-boot:run
mvn spring-boot:start
mvn spring-boot:stop
mvn spring-boot:build-image (builds docker image)