Release on Merge Action Source

This is the source code for Release on Merge Action. For usage documentation see the action definition repo.

What it does

A Rust binary packaged as a Docker-based GitHub Action that creates a GitHub release on every merge to main. It:

1. Reads configuration from GitHub Action inputs
2. Optionally resolves the increment strategy from the merged PR's labels
3. Fetches the latest release from the GitHub API
4. Increments the semver tag (stable or pre-release)
5. Creates a new GitHub release and writes version / tag outputs

Inputs

Input	Default	Description
version-increment-strategy	patch	major | minor | patch | norelease
initial-version	0.1.0	Version used when no prior release exists
tag-prefix	v	Prefix prepended to the version number
body	''	Text prepended to auto-generated release notes
generate-release-notes	true	Auto-generate GitHub release notes
dry-run	false	Log without creating the release
github-host	https://api.github.com	Override for GitHub Enterprise
prerelease	false	Create a pre-release with counter suffix
prerelease-identifier	rc	Identifier in the pre-release suffix (e.g. beta → v1.2.0-beta.1)
use-label-strategy	false	Derive strategy from merged PR labels
label-major	release:major	Label that triggers a major bump
label-minor	release:minor	Label that triggers a minor bump
label-patch	release:patch	Label that triggers a patch bump
label-skip	release:skip	Label that skips release creation

Outputs

Output	Example	Description
version	1.2.3 or 1.2.3-rc.1	Version number without prefix
tag	v1.2.3 or v1.2.3-rc.1	Full tag including prefix

Development

cargo build --release   # build
cargo test              # run all tests (31 tests)
cargo clippy            # lint

The Docker image is built and published to ghcr.io/dexwritescode/release-on-merge-action-source via the CD workflow when a GitHub release is published.