Spring BootのCI/CDパイプライン構築

Continuous Integration automatically builds and tests every code change, while Continuous Delivery automates packaging and deployment. Together they ship changes quickly and safely.

Manual builds and deploys are slow and error-prone. A pipeline gives fast feedback, consistent artifacts, and confidence that what you ship was tested.

A typical pipeline has clear stages run in order.

• Checkout code
• Build
• Run tests
• Package
• Deploy

Most pipelines trigger automatically when code is pushed or a pull request opens, ensuring every change is validated.

The pipeline runs your build tool to compile and execute the test suite. A failing test fails the pipeline, blocking bad code.

Downloading dependencies every run is slow. Caching the local Maven or Gradle repository between runs makes pipelines much faster.

After tests pass, the pipeline builds a Docker image. Spring Boot can even produce one without a Dockerfile.

The built image is tagged and pushed to a container registry, making it available for any environment to pull and run.

Never hardcode credentials in pipeline files. Use the platform's secret store and inject them as environment variables at runtime.

The final stage deploys the new image to staging or production, optionally requiring a manual approval gate before production.

Because each deploy uses an immutable, versioned image, rolling back is as simple as redeploying the previous tag, a key safety net.

You learned the stages of a CI/CD pipeline, automatic triggers, build-and-test steps, dependency caching, image building and pushing, secret management, and safe rollbacks with versioned images.