Enhancement: Add Docker Hub image (#965)

* Enhancement: Add Docker Hub image

* Push to ghcr.io

* Add all `org.opencontainers.image.xxx` labels using `--label` instead of `LABEL`

* Change `php-fpm` to listen on `:9000` to expose prometheus metrics via `php-fpm_exporter`

* Include `yarn.lock` to speed up builds

* Reorder

* Use correct sha for pr

* Add logging before overriding values in config

* Add `DEBUG=true` env var for verbose `entrypoint.sh` logs

* Print php exception when snappymail fails to generate data directory and config file on the very first time

* Log snappymail version

* Fix COPY statement

* Add .dockerignore

* Add `USER` and `ENTRYPOINT`

* Update `.dockerignore`

* Add docker image test

* Push only if image test succeeds

* Log when startup is successful

* Use plain `docker build` in `build_and_test.sh`

* Fix test output

.github/workflows/docker.yml

@@ -0,0 +1,127 @@
+name: docker
+
+on:
+  push:
+    branches:
+    - master
+    tags:
+    - '**'
+  # TODO: Remove this before merging PR
+  pull_request:
+    branches:
+    - master
+
+# This is needed to push to GitHub Container Registry. See https://docs.github.com/en/packages/working-with-a-github-packages-registry/working-with-the-container-registry
+permissions:
+  contents: read
+  packages: write
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+    - name: Checkout
+      uses: actions/checkout@v3
+
+    # This step generates the docker tags
+    # TODO: Remove type=ref,event=pr before merging PR
+    - name: Docker meta
+      id: meta
+      uses: docker/metadata-action@v4
+      env:
+        # This env var ensures {{sha}} is a real commit SHA for type=ref,event=pr
+        DOCKER_METADATA_PR_HEAD_SHA: 'true'
+      with:
+        images: |
+          ${{ github.repository }}
+          ghcr.io/${{ github.repository }}
+        # type=ref,event=pr generates tag(s) on PRs only. E.g. 'pr-123', 'pr-123-abc0123'
+        # type=ref,event=branch generates tag(s) on branch only. E.g. 'master', 'master-abc0123'
+        # type=ref,event=tag generates tag(s) on tags only. E.g. 'v0.0.0', 'v0.0.0-abc0123', and 'latest'
+        tags: |
+          type=ref,event=pr
+          type=ref,suffix=-{{sha}},event=pr
+          type=ref,event=branch
+          type=ref,suffix=-{{sha}},event=branch
+          type=ref,event=tag
+          type=ref,suffix=-{{sha}},event=tag
+        # The rest of the org.opencontainers.image.xxx labels are dynamically generated
+        labels: |
+          org.opencontainers.image.description=SnappyMail
+          org.opencontainers.image.licenses=AGPLv3
+
+    # See: https://github.com/docker/build-push-action/blob/v2.6.1/docs/advanced/cache.md#github-cache
+    - name: Set up QEMU
+      uses: docker/setup-qemu-action@v2
+
+    - name: Set up Docker Buildx
+      id: buildx
+      uses: docker/setup-buildx-action@v2
+
+    - name: Cache Docker layers
+      uses: actions/cache@v3
+      with:
+        path: /tmp/.buildx-cache
+        key: ${{ runner.os }}-buildx-${{ github.sha }}
+        restore-keys: |
+          ${{ runner.os }}-buildx-
+
+    - name: Login to Docker Hub registry
+      uses: docker/login-action@v2
+      with:
+        username: ${{ secrets.DOCKERHUB_USERNAME }}
+        password: ${{ secrets.DOCKERHUB_TOKEN }}
+
+    - name: Login to GitHub Container Registry
+      uses: docker/login-action@v2
+      with:
+        registry: ghcr.io
+        username: ${{ github.actor }}
+        password: ${{ secrets.GITHUB_TOKEN }}
+
+    # See: https://github.com/docker/buildx/issues/59
+    - name: Build
+      id: build
+      uses: docker/build-push-action@v3
+      with:
+        context: '.'
+        file: ./.docker/release/Dockerfile
+        platforms: linux/amd64
+        push: false
+        load: true
+        tags: ${{ steps.meta.outputs.tags }}
+        labels: ${{ steps.meta.outputs.labels }}
+        cache-from: type=local,src=/tmp/.buildx-cache
+        cache-to: type=local,dest=/tmp/.buildx-cache-new,mode=max
+
+    - name: Docker images
+      run: |
+        docker images
+
+    - name: Test
+      run: |
+        TAG=$( echo "${{ steps.meta.outputs.tags }}" | head -n1 )
+        .docker/release/test/test.sh "$TAG"
+
+    - name: Build and push
+      id: build-and-push
+      uses: docker/build-push-action@v3
+      with:
+        context: '.'
+        file: ./.docker/release/Dockerfile
+        # TODO: Add more arches?
+        # platforms: linux/386,linux/amd64,linux/arm/v6,linux/arm/v7,linux/arm64,linux/s390x
+        platforms: linux/386,linux/amd64
+        push: true
+        tags: ${{ steps.meta.outputs.tags }}
+        labels: ${{ steps.meta.outputs.labels }}
+        cache-from: type=local,src=/tmp/.buildx-cache
+        cache-to: type=local,dest=/tmp/.buildx-cache-new,mode=max
+
+    # Temp fix
+    # https://github.com/docker/build-push-action/issues/252
+    # https://github.com/moby/buildkit/issues/1896
+    - name: Move cache
+      run: |
+        rm -rf /tmp/.buildx-cache
+        mv /tmp/.buildx-cache-new /tmp/.buildx-cache