Add build action

.github/workflows/build.yml

@@ -0,0 +1,46 @@
+name: Build Container
+
+on:
+  push:
+    branches:
+      - main
+    tags:
+      - 'v*'
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    permissions:
+      contents: read
+      packages: write
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Generate metadata
+        id: meta
+        uses: docker/metadata-action@v5
+        with:
+          images: |
+            ghcr.io/${{ github.repository }}
+          tags: |
+            type=ref,event=branch
+            type=semver,pattern={{version}}
+            type=semver,pattern={{major}}.{{minor}}
+
+      - name: Login to GitHub Container Registry
+        uses: docker/#-action@v3
+        with:
+          registry: ghcr.io
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Build and push
+        uses: docker/build-push-action@v5
+        with:
+          context: .
+          push: ${{ github.event_name != 'pull_request' }}
+          tags: ${{ steps.meta.outputs.tags }}
+          labels: ${{ steps.meta.outputs.labels }}

README.md

@@ -11,6 +11,13 @@ you've downloaded the config file, put it in `./data/config`, and add the follow
 
     enableSemantics( 'localhost:8087' );
 
+### Deployment
+
+Push a tag for the version of mediawiki you're publishing, e.g. for mediawiki 1.39.6, the tag should be
+`v1.39.6-1`.
+
+Published to ghcr.io/emfcamp/docker-mediawiki.
+
 ## Updating
 
 If a mediawiki DB needs an upgrade: