Add forgejo actions

.forgejo/workflows/docker.yml

@@ -0,0 +1,74 @@
+# Based on https://github.com/docker/build-push-action
+
+name: "Docker"
+
+on:
+  release: # A GitHub release was published
+    types: [published]
+  workflow_dispatch: # A build was manually requested
+  workflow_call: # Another pipeline called us
+    secrets:
+      DOCKER_TOKEN:
+        required: true
+
+env:
+  GHCR_NAMESPACE: sigb.us
+  PLATFORMS: linux/amd64
+  FORGEJO_USER: signaryk
+
+jobs:
+  monolith:
+    name: Monolith image
+    runs-on: docker
+    image: ubuntu:latest
+    permissions:
+      contents: read
+      packages: write
+      security-events: write # To upload Trivy sarif files
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+      - name: Get release tag & build flags
+        if: github.event_name == 'release' # Only for GitHub releases
+        run: |
+          echo "RELEASE_VERSION=${GITHUB_REF#refs/*/}" >> $GITHUB_ENV
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v3
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+      - name: Login to sigb.us container registry
+        uses: docker/login-action@v3
+        with:
+          registry: git.sigb.us
+          username: ${{ env.FORGEJO_USER }}
+          password: ${{ secrets.FORGEJO_TOKEN }}
+
+      - name: Build main monolith image
+        if: github.ref_name == 'main'
+        id: docker_build_monolith
+        uses: docker/build-push-action@v3
+        with:
+          cache-from: type=registry,ref=git.sigb.us/${{ env.GHCR_NAMESPACE }}/dendrite-monolith:buildcache
+          cache-to: type=registry,ref=git.sigb.us/${{ env.GHCR_NAMESPACE }}/dendrite-monolith:buildcache,mode=max
+          context: .
+          platforms: ${{ env.PLATFORMS }}
+          push: true
+          tags: |
+            git.sigb.us/${{ env.GHCR_NAMESPACE }}/dendrite:${{ github.ref_name }}
+            git.sigb.us/${{ env.GHCR_NAMESPACE }}/dendrite:latest
+            git.sigb.us/${{ env.GHCR_NAMESPACE }}/dendrite:devel
+
+      - name: Build release monolith image
+        if: github.event_name == 'release' # Only for GitHub releases
+        id: docker_build_monolith_release
+        uses: docker/build-push-action@v3
+        with:
+          cache-from: type=gha
+          cache-to: type=gha,mode=max
+          context: .
+          platforms: ${{ env.PLATFORMS }}
+          push: true
+          tags: |
+            git.sigb.us/${{ env.GHCR_NAMESPACE }}/dendrite-monolith:latest
+            git.sigb.us/${{ env.GHCR_NAMESPACE }}/dendrite-monolith:stable
+            git.sigb.us/${{ env.GHCR_NAMESPACE }}/dendrite-monolith:${{ env.RELEASE_VERSION }}