Ultimate Node.js Dockerfile Assignment

You are the Node.js developer for the "Dog vs. Cat voting app" project. You are given a basic Dockerfile and the source code for the "result" Node.js app.

Goal: take the Dockerfile in this directory and make it the ULTIMATE for a combination of local development, production, and testing of the "result" app using all the things you learned in this section.

The finished Dockerfile should include

• Create a multi-stage Dockerfile that supports specific images for production, testing, and development.
• devDependencies should not exist in production image.
• Use npm ci to install production dependencies.
• Use Scenario 1 for setting up node_modules (the simple version).
• Set NODE_ENV properly for dev and prod.
• The dev stage should run nodemon from devDependencies. Either by updating the $PATH or hard-coding the path to nodemon.
• Edit docker-compose.yml to target the dev stage.
• Add LABELS from OCI standard (values are up to you) to all images.
• Add npm config list output before running npm install.
• Create a test stage that runs npm audit.
• ./tests directory should only exist in test image.
• Healthchecks should be added for production image.
• Prevent repeating costly commands like npm installs or apt-get.
• Only COPY . . source code once, then COPY --from to get it into other stages.

BONUS

• Add a security scanner to test stage and test it.
• Try using a Dockerfile ARG to add token to microscanner.
• Add Best Practices from earlier section, including:
  • Enable BuildKit and try a build.
  • Add tini to images so containers will receive shutdown signals.
  • Enable the non-root node user for all dev/prod images.
  • You might need root user for test or scanning images depending on what you're doing (test and find out!)

Things to test once finished to ensure it's working

• Build all stages as their own tag. ultimatenode:test should be bigger then ultimatenode:prod
• All builds should finish.
• Run dev/test/prod images, and ensure they start as expected.
• docker-compose up should work and you can vote at http://localhost:5000 and see results at http://localhost:5001.
• Ensure prod image doesn't have unnecessary files by running docker run -it <imagename>:prod bash and checking it:
  • ls contents of /app/node_modules/.bin, it should not contain nodemon or devDependencies.
  • ls contents of /app in prod image, it should not contain ./tests directory.
• After docker-compose up, run docker-compose exec result ./tests/tests.sh to perform a functional test across containers. After a moment delay, it should pass.

Good Luck!