add workflow for releasing from tag

Author: tjololo

.github/workflows/tag.yaml

@@ -0,0 +1,88 @@
+name: Build release from tag
+on:
+  push:
+    tags:
+      - 'v*.*.*'
+
+env:
+  ko_version: 0.12.0
+
+jobs:
+  publish_github:
+    name: Build latest and publish to ghcr
+    runs-on: ubuntu-latest
+    permissions:
+      packages: write
+    steps:
+      - name: Get version from tags
+        id: version
+        run: echo ::set-output name=tag::${GITHUB_REF/refs\/tags\//}
+
+      - name: Set up Go 1.x
+        uses: actions/setup-go@v3
+        with:
+          go-version: ^1.19
+
+      - name: Check out code into the Go module directory
+        uses: actions/checkout@v3
+
+      - name: Build
+        run: go build -v .
+
+      - name: Test
+        run: go test -v ./...
+
+      - name: Install KO
+        run: |
+          curl -L https://github.com/google/ko/releases/download/v${{ env.ko_version }}/ko_${{ env.ko_version }}_Linux_x86_64.tar.gz | tar xzf - ko
+          chmod +x ./ko
+      - name: Publish docker image
+        env:
+          KO_DOCKER_REPO: ghcr.io/${{ github.repository_owner }}
+        run: |
+          ./ko login ghcr.io --username $GITHUB_REPOSITORY_OWNER --password ${{ secrets.GITHUB_TOKEN }}
+          ./ko publish -B --tags v${{ steps.version.outputs.tag }} .
+  publish_google:
+    name: Build latest and publish to pkg.dev
+    runs-on: ubuntu-latest
+    permissions:
+      id-token: write
+      contents: read
+    steps:
+      - name: Get version from tags
+        id: version
+        run: echo ::set-output name=tag::${GITHUB_REF/refs\/tags\//}
+
+      - name: Set up Go 1.x
+        uses: actions/setup-go@v3
+        with:
+          go-version: ^1.19
+
+      - name: Check out code into the Go module directory
+        uses: actions/checkout@v3
+
+      - name: Build
+        run: go build -v .
+
+      - name: Test
+        run: go test -v ./...
+
+      - name: Install KO
+        run: |
+          curl -L https://github.com/google/ko/releases/download/v${{ env.ko_version }}/ko_${{ env.ko_version }}_Linux_x86_64.tar.gz | tar xzf - ko
+          chmod +x ./ko
+      - name: Authenticate with Google Cloud
+        id: auth
+        uses: google-github-actions/auth@v1
+        with:
+          token_format: access_token
+          workload_identity_provider: ${{ secrets.GCP_IDENTITY_PROVIDER }}
+          service_account: ${{ secrets.GCP_SERVICE_ACCOUNT }}
+          access_token_lifetime: 300s
+
+      - name: Publish docker image
+        env:
+          KO_DOCKER_REPO: europe-north1-docker.pkg.dev/cloud-418/mope
+        run: |
+          ./ko login europe-north1-docker.pkg.dev --username oauth2accesstoken --password ${{ steps.auth.outputs.access_token }}
+          ./ko publish -B --tags v${{ steps.version.outputs.tag }} .