image.yml

name: Build Image (edge)

# Every merge to main pushes an immutable sha-tagged image plus a moving
# `edge` tag. Nothing deploys from here — deploys happen on release publish
# (deploy.yml). This keeps every merge one dispatch away from prod (or from
# a rollback) and keeps the buildx cache warm so release builds are fast.
#
# workflow_dispatch builds ANY ref (e.g. a feature branch for the beta
# slice) as a sha-only image — the `edge` tag is guarded to push events
# so branch builds can never steal it from main.

on:
  push:
    branches:
      - main
    paths-ignore:
      - '**/*.md'
      - '**/*.rst'
      - 'docs/**'
  workflow_dispatch:

permissions:
  contents: read

env:
  REGISTRY: ghcr.io
  IMAGE_NAME: ${{ github.repository }}

jobs:
  build:
    runs-on: ubuntu-latest
    permissions:
      contents: read
      packages: write

    steps:
      - name: Checkout
        uses: actions/checkout@v7
        with:
          persist-credentials: false

      - name: Set up Docker Buildx
        uses: docker/setup-buildx-action@v4

      - name: Log in to GHCR
        uses: docker/login-action@v4
        with:
          registry: ${{ env.REGISTRY }}
          username: ${{ github.actor }}
          password: ${{ secrets.GHCR_PAT }}

      - name: Short sha
        id: sha
        run: echo "short=${GITHUB_SHA::7}" >> "$GITHUB_OUTPUT"

      - name: Extract metadata
        id: meta
        uses: docker/metadata-action@v6
        with:
          images: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
          tags: |
            type=raw,value=edge,enable=${{ github.event_name == 'push' }}
            type=sha,prefix=,format=short

      - name: Build and push
        uses: docker/build-push-action@v7
        with:
          context: .
          push: true
          tags: ${{ steps.meta.outputs.tags }}
          labels: ${{ steps.meta.outputs.labels }}
          build-args: |
            APP_VERSION=${{ steps.sha.outputs.short }}
          cache-from: type=gha
          cache-to: type=gha,mode=max
          platforms: linux/amd64