implemented gh package creation

.github/workflows/build.yaml

@@ -0,0 +1,45 @@
+name: Build and deploy containers
+# Pushes to main will build containers with staging env's and push them as staging images, whereas release goes to production.
+on:
+  release:
+    types: [published]
+  push:
+    branches:
+      - main
+env:
+  IMAGE_NAME: ${{ github.event_name == 'release' && 'brewery' || 'brewery-staging' }}
+
+jobs:
+  push_backend:
+    if: ${{ github.event_name == 'release' || (github.event_name == 'push' && !contains(github.event.head_commit.message, '#no-deploy')) }}
+    runs-on: ubuntu-latest
+    permissions:
+      packages: write
+      contents: read
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Build image
+        run: docker build . --file backend/Dockerfile.self-host --tag $IMAGE_NAME --label "runnumber=${GITHUB_RUN_ID}"
+
+      - name: Log in to registry
+        run: echo "${{ secrets.GITHUB_TOKEN }}" | docker login ghcr.io -u ${{ github.actor }} --password-stdin
+        #
+      - name: Push image
+        run: |
+          IMAGE_ID=ghcr.io/${{ github.repository_owner }}/$BACKEND_IMAGE_NAME
+
+          # This changes all uppercase characters to lowercase.
+          IMAGE_ID=$(echo $IMAGE_ID | tr '[A-Z]' '[a-z]')
+
+          # This strips the git ref prefix from the version.
+          VERSION=$(echo "${{ github.ref }}" | sed -e 's,.*/\(.*\),\1,')
+
+          # This strips the "v" prefix from the tag name.
+          [[ "${{ github.ref }}" == "refs/tags/"* ]] && VERSION=$(echo $VERSION | sed -e 's/^v//')
+
+          VERSION=latest
+          echo IMAGE_ID=$IMAGE_ID
+          echo VERSION=$VERSION
+          docker tag $BACKEND_IMAGE_NAME $IMAGE_ID:$VERSION
+          docker push $IMAGE_ID:$VERSION