prepare docker image for quay, pushing via goreleaser

.goreleaser.yml

@@ -26,3 +26,34 @@ checksum:
 
 snapshot:
   name_template: "{{ .Tag }}-snapshot"
+
+# to push to quay
+dockers:
+  -
+    # GOOS of the built binary that should be used.
+    goos: linux
+
+    # GOARCH of the built binary that should be used.
+    goarch: amd64
+
+    # Name templates of the built binaries that should be used.
+    binaries:
+    - gman
+
+    # Templates of the Docker image names.
+    image_templates:
+    - "quay.io/kubermatic-labs/gman:{{ .Tag }}"
+
+    # Skips the docker push. Could be useful if you also do draft releases.
+    skip_push: false
+
+    # Path to the Dockerfile (from the project root).
+    dockerfile: Dockerfile
+
+    # If your Dockerfile copies files other than the binary itself,
+    # you should list them here as well.
+    # the paths here are relative to the folder in which goreleaser is being run.
+    #extra_files:
+    #- README.md
+    #- LICENSE
+    #- config.example.yaml

Dockerfile

@@ -0,0 +1,29 @@
+FROM golang:alpine AS builder
+RUN apk add git
+# necessary environmet variables
+ENV GO111MODULE=on \
+    CGO_ENABLED=0 \
+    GOOS=linux \
+    GOARCH=amd64
+
+WORKDIR /build
+COPY go.mod .
+COPY go.sum .
+RUN go mod download
+
+# Copy the code into the container & build
+COPY main.go .
+RUN go build -o gman main.go 
+
+WORKDIR /app
+
+# Copy binary from build to main folder
+RUN cp /build/gman .
+
+# Build a small image
+FROM scratch
+
+COPY --from=builder /app/gman /
+
+# Command to run
+ENTRYPOINT ["/gman"]