ci: Build secrets server on PRs, publish on releases. (#1)

Co-authored-by: jmug <u.g.a.mariano@gmail.com>
Reviewed-on: #1

.gitea/workflows/build-secretsserver.yaml

@@ -0,0 +1,42 @@
+name: build-secretsserver
+
+on:
+  push:
+    branches:
+      - main
+  # Only run on release tags.
+  tags: ["v*"]
+  pull_request:
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v5
+
+      # Unfortunately gotta use a PAT,
+      # workflow tokens can't access the registry yet.
+      - name: Log in to the registry
+        if: ${{ gitea.ref_type == 'tag' }}
+        uses: docker/login-action@v3
+        with:
+          registry: git.handmadecities.com
+          username: ${{ secrets.REGISTRY_USER }}
+          password: ${{ secrets.REGISTRY_TOKEN }}
+
+      - name: Compute tags
+        id: meta
+        uses: docker/metadata-action@v5
+        with:
+          images: git.handmadecities.com/${{ gitea.repository }}/secretsserver
+          tags: |
+            type=semver,pattern={{version}}
+
+      - name: Build and push
+        uses: docker/build-push-action@v6
+        with:
+          file: docker/secretsserver/Dockerfile
+          context: .
+          # Only push on releases.
+          push: ${{ gitea.ref_type == 'tag' }}
+          tags: ${{ steps.meta.outputs.tags }}