Add Docker support and GitHub Container Registry CI workflow

[kjanat]

Overview

This PR adds comprehensive Docker support and sets up CI workflows for building and pushing Docker images to the GitHub Container Registry (GHCR).

Changes Made

Docker Infrastructure

• Dockerfile: Multi-stage build using golang:1.23-alpine for builder and scratch for runtime

  • Optimized for small image size
  • Includes build args for version, build time, and git commit injection
  • Non-root user execution for security

• .dockerignore: Optimizes build context by excluding unnecessary files

• docker-compose.yml: Local development and testing setup

CI/CD Enhancements

• Enhanced CI workflow (.github/workflows/ci.yml): Added Docker build and push job
• Dedicated Docker workflow (.github/workflows/docker.yml): Separate workflow for Docker operations
• GitHub Container Registry integration: Automatic image publishing with proper tagging strategy
  • Tags: latest and version-based tags
  • Metadata labels for better image management

Application Improvements

• Enhanced main.go: Added --help flag support displaying:
  • Version information
  • Build timestamp
  • Git commit hash
  • Usage instructions

Documentation

• Updated README.md: Comprehensive Docker section including:
  • Installation instructions
  • Usage examples
  • Development setup
  • Docker badge and reference links

Docker Usage

Pull and run from GHCR:

docker run --rm -v $(pwd):/data ghcr.io/kjanat/articulate-parser:latest /data/input.txt

Local development:

docker-compose up --build

Testing

• Docker image builds successfully
• Application runs correctly in container
• Help flag displays version information
• Multi-architecture support ready
• CI pipeline execution (will be tested after merge)
• GHCR image push verification (will be verified after merge)

Security Considerations

• Uses scratch base image for minimal attack surface
• Runs as non-root user
• Optimized build context with .dockerignore
• Proper secret handling in CI workflows

This enhancement makes the articulate-parser easily deployable and integrates seamlessly with containerized workflows.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

📢 Thoughts on this report? Let us know!

[Copilot]

Pull Request Overview

This PR adds comprehensive Docker support and integrates GitHub Container Registry CI workflows for building, tagging, and pushing Docker images, while also improving application usability through a new help flag.

• Updates Docker infrastructure with a multi-stage Dockerfile, .dockerignore, and docker-compose configuration.
• Enhances CI/CD by adding dedicated workflows for Docker testing, build, and push operations.
• Improves documentation in the README with detailed usage instructions and badge indicators.

Reviewed Changes

Copilot reviewed 8 out of 8 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
main.go	Adds a help flag to display usage and version information.
docker-compose.yml	Introduces multiple service definitions for local development and file processing.
README.md	Documents Docker image usage, available tags, and usage examples.
Dockerfile	Implements a multi-stage build including build metadata injection and a scratch runtime image.
.github/workflows/docker.yml	Provides CI workflow for testing, building, and pushing Docker images.
.github/workflows/ci.yml	Integrates Docker build & push steps within the CI pipeline.
.github/dependabot.yml	Adds update checks for Docker and Docker Compose.
.dockerignore	Optimizes the build context by excluding non-essential files.

[Copilot]

Pull Request Overview

This PR integrates Docker support and sets up CI workflows to build and publish Docker images to GitHub Container Registry.

• Introduces multi-stage Dockerfiles and docker-compose.yml for local development.
• Updates CI (ci.yml) to cache modules, run Docker build/tests, and push images.
• Expands documentation (README.md, DOCKER.md) with Docker usage, badges, and Dependabot updates.

Reviewed Changes

Copilot reviewed 11 out of 11 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
main_test.go	Renamed test field and added TestRunWithHelpFlags cases
main.go	Added help-flag handling in run()
docker-compose.yml	Configured services for local and dev scenarios
README.md	Added Docker badges and detailed usage sections
Dockerfile.dev	New development Dockerfile with shell access
Dockerfile	New production multi-stage Dockerfile
DOCKER.md	Dedicated Docker documentation
.github/workflows/ci.yml	Enhanced CI for Docker build/test and caching
.github/dependabot.yml	Added Docker and Docker Compose update checks
.dockerignore	Extended ignore patterns for container builds

Comments suppressed due to low confidence (2)

main_test.go:18

• [nitpick] The field name str is generic; consider reverting to input or a more descriptive name to improve test readability.

str      string

README.md:215

• [nitpick] The Docker size in README (~15–20MB) conflicts with DOCKER.md (<10MB). Please reconcile the actual image size or remove the approximation.

| **Size**: ~15-20MB compressed

[Copilot]

Pull Request Overview

Adds Docker support and CI workflows for building, testing, and publishing container images to GitHub Container Registry.

• Introduces multi-stage Dockerfiles (Dockerfile & Dockerfile.dev) and docker-compose.yml for local development and minimal runtime images
• Enhances CI/CD (.github/workflows/ci.yml) with Docker build/test jobs, retryable dependency downloads, caching, and metadata-driven image publishing
• Updates main.go and main_test.go to support --help/--version flags, and revises documentation (README.md, DOCKER.md) with Docker usage instructions

Reviewed Changes

Copilot reviewed 14 out of 14 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
main.go	Added version/help flag handling and extracted usage printing logic
main_test.go	Renamed test fields, added tests for help/version flags
Dockerfile & Dockerfile.dev	Defined multi-stage builds with non-root user, metadata labels
docker-compose.yml	Local development services for parser and shell access
README.md & DOCKER.md	Documented Docker image usage, tags, compose, and registry details
.github/workflows/ci.yml	Extended CI with Docker build/test jobs, caching, retries, and summary
.github/dependabot.yml	Added Docker and Docker Compose update checks
.dockerignore	Excluded unnecessary files from Docker build context

Comments suppressed due to low confidence (6)

main_test.go:18

• [nitpick] The field name str is ambiguous compared to the function parameter input; consider renaming it back to input for clarity and consistency.

str      string

main.go:90

• Manual string concatenation in a loop can be less efficient; consider using strings.Join(strs, sep) for better performance and readability.

func joinStrings(strs []string, sep string) string {

Dockerfile.dev:46

• The go build invocation dropped the -ldflags and -o articulate-parser flags, so the binary will be named main without embedded version info; restore those flags and output name.

./main.go

Dockerfile:43

• Similar to Dockerfile.dev, this build command removed the -ldflags and -o articulate-parser options, resulting in a misnamed binary and missing metadata; reintroduce those flags.

./main.go

main_test.go:246

• The new tests use os, io, bytes, and strings but these packages aren’t imported at the top; add the missing imports to ensure the tests compile.

oldStdout := os.Stdout

DOCKER.md:25

• The example omits the required <format> and <output> arguments; update it to ...:latest <source> <format> <output> to match printUsage expectations.

docker run --rm -v $(pwd):/data ghcr.io/kjanat/articulate-parser:latest /data/document.txt

[kjanat]

This pull request introduces significant updates to the CI/CD pipeline, Docker integration, and repository configuration. Key changes include the addition of .dockerignore, new workflows for dependency review and release management, enhancements to the CI pipeline for caching and Docker testing, and the inclusion of a detailed DOCKER.md guide.

CI/CD Pipeline Enhancements:

• Caching and Dependency Management: Added custom caching for Go modules and implemented retry logic for downloading dependencies in .github/workflows/ci.yml. This improves reliability and reduces build times.
• Docker Testing: Introduced a docker-test job to validate Docker image builds and test their functionality.
• Concurrency Control: Enabled concurrency groups to cancel in-progress workflows for the same branch in .github/workflows/ci.yml.

Docker Integration:

• Docker Build Workflow: Added a docker job to build and push multi-architecture Docker images to GitHub Container Registry, including metadata, SBOM, and provenance attestation.
• DOCKER.md Documentation: Added a comprehensive guide for using the Docker image, including usage examples, available tags, and development instructions.

Repository Configuration:

• .dockerignore File: Added .dockerignore to exclude unnecessary files from Docker image builds, reducing image size and build context.
• Dependabot Updates: Configured Dependabot to monitor Docker and Docker Compose dependencies in .github/dependabot.yml.

New Workflows:

• Dependency Review Workflow: Added .github/workflows/dependency-review.yml to review dependencies for vulnerabilities, triggered via workflow_call.
• Release Workflow: Introduced .github/workflows/release.yml to automate release creation, including binary compression and tagging.