GitHub Action

The action analyses the base and head of each pull request, uploads the map and the report as an artifact and leaves a comment with the architecture diff. Today it is used through a subpath of the monorepo.

Usage

.github/workflows/codarch.yml:

name: CodArch
on: pull_request
permissions:
  contents: read
  pull-requests: write
jobs:
  codarch:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v7
        with: { fetch-depth: 0 }
      - uses: jaminsmoke/codarch/apps/github-action@v1
        with:
          github-token: ${{ secrets.GITHUB_TOKEN }}
          fail-on: none

fetch-depth: 0 is required: the base is computed from the merge-base and analysed in a git worktree.
The action installs codarch from npm; it does not need CodArch’s code nor run npm ci on your project. The version is pinned with version.

What it produces

One comment, updated: it carries the  marker; each push edits the same comment instead of creating another.
An artifact (codarch): the base and head snapshots, the head map, report.json and the capture head/map.png with its summary in head/map.json.

The comment links that capture and writes what the PNG does not say: which area and colour it is painted with, the scale and the five largest cells. The image cannot be embedded in a comment —GitHub drops the ones without a URL—, so it lives in the artifact.

Warn or block

`fail-on`	Blocks when
`none` (default)	never: it comments and uploads the artifact
`violations`	there are new `.codarch.yml` violations
`cycles`	new cycles appear
`hotspots`	new hotspots appear
`any`	any of the above

Only what the PR introduces blocks. Exit code 2: policy broken; 1: analysis or configuration error. Each rule’s severity (info/warn/error) is decided in .codarch.yml.

Inputs

github-token, base-ref, base-sha, fail-on, config (default .codarch.yml; none disables it), comment, artifact-name, node-version, version, working-directory, title and top. The full list with defaults is in apps/github-action/action.yml.

Forks

On PRs from forks the token is usually read-only: the comment is skipped with a warning, but the analysis and the artifact still work.