ci: add basic github actions for build/release

.github/workflows/build.yml

@@ -29,3 +29,10 @@ jobs:
       run: |
         shellcheck -V
         shellcheck --shell bash shepherd
+  
+  build:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v3
+    - name: Build Docker image
+      run: docker build .

.github/workflows/release.yml

@@ -0,0 +1,91 @@
+name: Release
+
+on:
+  push:
+    branches: [ "master" ]
+    # Publish semver tags as releases.
+    tags: [ 'v*.*.*' ]
+  workflow_dispatch:
+
+env:
+  # github.repository as <account>/<repo>
+  IMAGE_NAME: ${{ github.repository }}
+
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+      packages: write
+      # This is used to complete the identity challenge
+      # with sigstore/fulcio 
+      id-token: write
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v3
+
+      # Install the cosign tool
+      # https://github.com/sigstore/cosign-installer
+      - name: Install cosign
+        uses: sigstore/cosign-installer@f3c664df7af409cb4873aa5068053ba9d61a57b6 #v2.6.0
+        with:
+          cosign-release: 'v1.13.1'
+
+
+      # Workaround: https://github.com/docker/build-push-action/issues/461
+      - name: Setup Docker buildx
+        uses: docker/setup-buildx-action@79abd3f86f79a9d68a23c75a09a9a85889262adf
+
+      # https://github.com/docker/login-action
+      - name: Login to GHCR
+        uses: docker/login-action@28218f9b04b4f3f62068d7b6ce6ca5b26e35336c
+        with:
+          registry: ghcr.io
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+
+      # Pushing to docker hub is disabled until repo is prepared
+
+      # https://github.com/docker/login-action
+      # - name: Login to docker hub
+      #   uses: docker/login-action@28218f9b04b4f3f62068d7b6ce6ca5b26e35336c
+      #   with:
+      #     registry: docker.io
+      #     username: ${{ secrets.DOCKERHUB_USERNAME }}
+      #     password: ${{ secrets.DOCKERHUB_TOKEN }}
+
+      # Extract metadata (tags, labels) for Docker
+      # https://github.com/docker/metadata-action
+      - name: Extract Docker metadata
+        id: meta
+        uses: docker/metadata-action@98669ae865ea3cffbcbaa878cf57c20bbf1c6c38
+        with:
+          images: |
+            ghcr.io/${{ env.IMAGE_NAME }}
+        # ${{ env.IMAGE_NAME }}
+
+      # Build and push Docker image with Buildx
+      # https://github.com/docker/build-push-action
+      - name: Build and push Docker image
+        id: build-and-push
+        uses: docker/build-push-action@ac9327eae2b366085ac7f6a2d02df8aa8ead720a
+        with:
+          context: .
+          tags: ${{ steps.meta.outputs.tags }}
+          labels: ${{ steps.meta.outputs.labels }}
+          platforms: linux/amd64,linux/arm64,linux/armhf
+          cache-from: type=gha
+          cache-to: type=gha,mode=max
+
+      # This will only write to the public Rekor transparency log when the Docker
+      # repository is public to avoid leaking data.  If you would like to publish
+      # transparency data even for private images, pass --force to cosign below.
+      # https://github.com/sigstore/cosign
+      - name: Sign the published Docker image
+        env:
+          COSIGN_EXPERIMENTAL: "true"
+        # This step uses the identity token to provision an ephemeral certificate
+        # against the sigstore community Fulcio instance.
+        run: echo "${{ steps.meta.outputs.tags }}" | xargs -I {} cosign sign {}@${{ steps.build-and-push.outputs.digest }}