Docker cache for multi-module Maven project

This project demonstrates how to write a multi-stage Dockerfile for a multi-module Maven project, so that Maven dependencies are cached in the early Docker layers of a builder stage and also how to use a layered JAR to create cache layers in the final Docker image.

In this project the user-app module depends on a common module.

Using BuildKit

DOCKER_BUILDKIT='1' docker build \
    -t pgpb/user-app:local \
    -f docker/user-app.dockerfile . \
    && docker run -it pgpb/user-app:local

Without BuildKit

docker build \
    -t pgpb/user-app:local \
    -f docker/user-app.dockerfile . \
    && docker run -it pgpb/user-app:local

References

• Creating Docker images with Spring Boot. Shows how to use a layered JAR to cache layers in the final stage of the multi-stage Dockerfile. However, it does not cover how to cache layers for the first stage.
• Multi-stage Dockerfile