Improve Docker build

Signed-off-by: Mark Sagi-Kazar <mark.sagikazar@gmail.com>

.github/workflows/ci.yml

@@ -1,9 +1,13 @@
 name: CI
 
 on:
+  schedule:
+    - cron: '0 5 * * *' # everyday at 5 am UTC
   push:
     branches:
       - master
+    tags:
+      - v[0-9]+.[0-9]+.[0-9]+
   pull_request:
 
 jobs:
@@ -87,21 +91,40 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-      - name: Checkout code
+      - name: Checkout
         uses: actions/checkout@v2
 
-      - name: Get Version
-        id: info
+      - name: Calculate Docker image tags
+        id: tags
+        env:
+          DOCKER_IMAGES: "ghcr.io/dexidp/dex dexidp/dex"
         run: |
-          echo ::set-output name=created::$(date -u +'%Y-%m-%dT%H:%M:%SZ')
+          VERSION=noop
 
-      - name: Determine Docker Tag
-        uses: haya14busa/action-cond@v1
-        id: imagetag
-        with:
-          cond: ${{ github.event_name == 'pull_request' }}
-          if_true: ${{ github.sha }}
-          if_false: 'master'
+          if [[ "${{ github.event_name }}" == "schedule" ]]; then
+            VERSION=nightly
+          else
+            case $GITHUB_REF in
+              refs/tags/*)  VERSION=${GITHUB_REF#refs/tags/};;
+              refs/heads/*) VERSION=$(echo ${GITHUB_REF#refs/heads/} | sed -r 's#/+#-#g');;
+              refs/pull/*)  VERSION=pr-${{ github.event.number }};;
+              *)            VERSION=sha-${GITHUB_SHA::8};;
+            esac
+          fi
+
+          TAGS=()
+          for image in $DOCKER_IMAGES; do
+            TAGS+=("${image}:${VERSION}")
+
+            if [[ "${{ github.event.repository.default_branch }}" == "$VERSION" ]]; then
+              TAGS+=("${image}:latest")
+            fi
+          done
+
+          echo ::set-output name=version::${VERSION}
+          echo ::set-output name=tags::$(IFS=,; echo "${TAGS[*]}")
+          echo ::set-output name=commit_hash::${GITHUB_SHA::8}
+          echo ::set-output name=build_date::$(git show -s --format=%cI)
 
       - name: Set up QEMU
         uses: docker/setup-qemu-action@v1
@@ -109,7 +132,6 @@ jobs:
           platforms: all
 
       - name: Set up Docker Buildx
-        id: buildx
         uses: docker/setup-buildx-action@v1
         with:
           install: true
@@ -117,27 +139,39 @@ jobs:
           # TODO: Remove driver-opts once fix is released docker/buildx#386
           driver-opts: image=moby/buildkit:master
 
-      - name: Login to DockerHub
+      - name: Login to GitHub Container Registry
+        uses: docker/login-action@v1
+        with:
+          registry: ghcr.io
+          username: ${{ github.repository_owner }}
+          password: ${{ secrets.CR_PAT }}
+        if: github.event_name == 'push'
+
+      - name: Login to Docker Hub
         uses: docker/login-action@v1
         with:
           username: ${{ secrets.DOCKER_USERNAME }}
           password: ${{ secrets.DOCKER_PASSWORD }}
         if: github.event_name == 'push'
 
-      - name: Build and Push
+      - name: Build and push
         uses: docker/build-push-action@v2
         with:
           context: .
-          file: Dockerfile
           platforms: linux/amd64,linux/arm/v7,linux/arm64
           push: ${{ github.event_name == 'push' }}
-          tags: dexidp/dex:${{ steps.imagetag.outputs.value }}
+          tags: ${{ steps.tags.outputs.tags }}
+          build-args: |
+            VERSION=${{ steps.tags.outputs.version }}
+            COMMIT_HASH=${{ steps.tags.outputs.commit_hash }}
+            BUILD_DATE=${{ steps.tags.outputs.build_date }}
           labels: |
             org.opencontainers.image.title=${{ github.event.repository.name }}
             org.opencontainers.image.description=${{ github.event.repository.description }}
             org.opencontainers.image.url=${{ github.event.repository.html_url }}
             org.opencontainers.image.source=${{ github.event.repository.clone_url }}
-            org.opencontainers.image.version=${{ steps.imagetag.outputs.value }}
-            org.opencontainers.image.created=${{ steps.info.outputs.created }}
+            org.opencontainers.image.version=${{ steps.tags.outputs.version }}
+            org.opencontainers.image.created=${{ steps.tags.outputs.build_date }}
             org.opencontainers.image.revision=${{ github.sha }}
             org.opencontainers.image.licenses=${{ github.event.repository.license.spdx_id }}
+            org.opencontainers.image.documentation=https://dexidp.io/docs/