Docker GCR job

Pushes a prebuilt docker image to GCR

.github/workflows/gcr.yml

@@ -0,0 +1,56 @@
+name: Docker Registry
+
+on:
+  schedule:
+    # https://crontab.guru/#0_4_*_*_*
+    - cron: '0 4 * * *' # everyday at 04AM
+  workflow_dispatch:
+  push:
+    branches:
+      - '**'
+    tags:
+      - "v*.*.*"
+  pull_request:
+    branches:
+      - 'master'
+
+jobs:
+  docker:
+    name: Build image and push to GCR
+    runs-on: ubuntu-latest
+    steps:
+      -   name: Checkout
+          uses: actions/checkout@v2
+      -   name: Docker metainformation
+          id: docker_meta
+          uses: crazy-max/ghaction-docker-meta@v1
+          with:
+            images: |
+              ghcr.io/it2901-sintef01/frontend
+            tag-sha: true
+      -   name: Set up QEMU
+          uses: docker/setup-qemu-action@v1
+      -   name: Set up Docker Buildx
+          uses: docker/setup-buildx-action@v1
+      -   name: Cache Docker layers
+          uses: actions/[email protected]
+          with:
+            path: /tmp/.buildx-cache
+            key: ${{ runner.os }}-buildx-${{ github.sha }}
+            restore-keys: |
+              ${{ runner.os }}-buildx-
+      -   name: Login to GitHub Container Registry
+          if: github.event_name != 'pull_request'
+          uses: docker/login-action@v1
+          with:
+            registry: ghcr.io
+            username: ${{ github.repository_owner }}
+            password: ${{ secrets.CR_PAT }}
+      -   name: Build and push production image
+          id: docker_build
+          uses: docker/build-push-action@v2
+          with:
+            context: .
+            push: ${{ github.event_name != 'pull_request' }}
+            tags: ${{ steps.docker_meta.outputs.tags }}
+            labels: ${{ steps.docker_meta.outputs.labels }}

Dockerfile

@@ -23,4 +23,6 @@ COPY nginx/nginx.conf /etc/nginx/conf.d
 # Doesn't really do anything, but serves as a hint you should forward the port to the host computer
 EXPOSE 80
 
+LABEL org.opencontainers.image.source=https://github.com/it2901-sintef01/frontend
+
 ENTRYPOINT ["nginx", "-g", "daemon off;"]