GoReleaser: add Docker support

.github/workflows/release.yml

@@ -23,6 +23,13 @@ jobs:
         with:
           go-version: 1.14
 
+      - name: Docker Login
+        env:
+          DOCKER_USERNAME: ${{ secrets.DOCKER_USERNAME }}
+          DOCKER_ACCESS_TOKEN: ${{ secrets.DOCKER_ACCESS_TOKEN }}
+        run: |
+          echo "${DOCKER_ACCESS_TOKEN}" | docker login --username "${DOCKER_USERNAME}" --password-stdin
+
       - name: Generate release info
         run: make build/release-info
 
@@ -33,3 +40,8 @@ jobs:
           args: release --rm-dist --release-notes=./build/release-info
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+
+     - name: Cleanup
+       if: always()
+       run: |
+         rm -f ${HOME}/.docker/config.json

.goreleaser.yml

@@ -12,6 +12,22 @@ builds:
 archives:
   - name_template: "{{ .ProjectName }}-{{ .Version }}-{{ .Os }}-{{ .Arch }}"
 
+dockers:
+  - image_templates:
+      - "sapcc/absent-metrics-operator:{{ .Tag }}"
+      - "sapcc/absent-metrics-operator:v{{ .Major }}.{{ .Minor }}"
+      - "sapcc/absent-metrics-operator:latest"
+    dockerfile: Dockerfile.goreleaser
+    binaries:
+      - absent-metrics-operator
+    build_flag_templates:
+      - "--pull"
+      - "--label=org.opencontainers.image.created={{.Date}}"
+      - "--label=org.opencontainers.image.revision={{.FullCommit}}"
+      - "--label=org.opencontainers.image.source={{.GitURL}}"
+      - "--label=org.opencontainers.image.title={{.ProjectName}}"
+      - "--label=org.opencontainers.image.version={{.Version}}"
+
 checksum:
   name_template: "checksums.txt"
 

Dockerfile.goreleaser

@@ -0,0 +1,10 @@
+# We use this additional file instead of the other Dockerfile because
+# GoReleaser already compiles a static binary and we can just copy it over
+# compared to the other Dockerfile which first compiles it.
+#
+# This saves extra work and time in our CI release workflow.
+FROM alpine:latest
+
+RUN apk add --no-cache ca-certificates
+COPY absent-metrics-operator /usr/bin/
+ENTRYPOINT [ "/usr/bin/absent-metrics-operator" ]