Add build target which creates debug image

Dockerfile.delve

@@ -0,0 +1,30 @@
+FROM golang:1.21-alpine3.19 AS build
+
+ARG TARGETOS
+ARG TARGETARCH
+ARG BUILDTARGET=rollout-operator-debug
+
+RUN apk add --no-cache build-base git
+
+COPY . /src/rollout-operator
+WORKDIR /src/rollout-operator
+RUN go install github.com/go-delve/delve/cmd/[email protected]
+RUN /go/bin/dlv -h
+RUN GOOS=${TARGETOS} GOARCH=${TARGETARCH} make ${BUILDTARGET}
+
+FROM alpine:3.19
+RUN apk add --no-cache ca-certificates
+
+COPY --from=build /go/bin/dlv /bin/dlv
+COPY --from=build /src/rollout-operator/rollout-operator /bin/rollout-operator
+ENTRYPOINT [ "/bin/dlv", "--headless=true", "--listen=:49988", "--api-version=2", "--accept-multiclient", "exec", "/bin/rollout-operator" , "--continue", "--"]
+
+# Create rollout-operator user to run as non-root.
+RUN addgroup -g 10000 -S rollout-operator && \
+    adduser  -u 10000 -S rollout-operator -G rollout-operator
+USER rollout-operator:rollout-operator
+
+ARG revision
+LABEL org.opencontainers.image.title="rollout-operator-debug" \
+    org.opencontainers.image.source="https://github.com/grafana/rollout-operator" \
+    org.opencontainers.image.revision="${revision}"

Makefile

@@ -4,6 +4,7 @@ GIT_REVISION := $(shell git rev-parse --short HEAD)
 
 IMAGE_PREFIX ?= grafana
 IMAGE_TAG ?= $(subst /,-,$(GIT_BRANCH))-$(GIT_REVISION)
+IMAGE_TAG_DEBUG ?= $(IMAGE_TAG)-debug
 
 GOOS ?= $(shell go env GOOS)
 GOARCH ?= $(shell go env GOARCH)
@@ -21,6 +22,9 @@ help: ## Display this help and any documented user-facing targets
 rollout-operator: $(GO_FILES) ## Build the rollout-operator binary
 	GOOS=$(GOOS) GOARCH=$(GOARCH) CGO_ENABLED=0 go build -ldflags '-extldflags "-static"' ./cmd/rollout-operator
 
+rollout-operator-debug: $(GO_FILES) ## Build the rollout-operator binary without optimizations
+	GOOS=$(GOOS) GOARCH=$(GOARCH) CGO_ENABLED=0 go build  -gcflags "all=-N -l" -ldflags '-extldflags "-static"' ./cmd/rollout-operator
+
 .PHONY: rollout-operator-boringcrypto
 rollout-operator-boringcrypto: $(GO_FILES) ## Build the rollout-operator binary with boringcrypto
 	GOEXPERIMENT=boringcrypto GOOS=$(GOOS) GOARCH=$(GOARCH) CGO_ENABLED=1 go build -tags netgo ./cmd/rollout-operator
@@ -29,6 +33,15 @@ rollout-operator-boringcrypto: $(GO_FILES) ## Build the rollout-operator binary
 build-image: clean ## Build the rollout-operator image
 	docker buildx build --load --platform linux/amd64 --build-arg revision=$(GIT_REVISION) -t rollout-operator:latest -t rollout-operator:$(IMAGE_TAG) .
 
+# Separate build targets per architecture because docker exporter currently doesn't support multi-arch builds on mac.
+.PHONY: build-debug-image-amd64 ## Build a rollout-operator debug image running in delve
+build-debug-image-amd64: clean
+	docker buildx build --load --platform linux/amd64 --build-arg revision=$(GIT_REVISION) -t rollout-operator:$(IMAGE_TAG_DEBUG) -f Dockerfile.delve .
+
+.PHONY: build-debug-image-arm64 ## Build a rollout-operator debug image running in delve
+build-debug-image-arm64: clean
+	docker buildx build --load --platform linux/arm64 --build-arg revision=$(GIT_REVISION) -t rollout-operator:$(IMAGE_TAG_DEBUG) -f Dockerfile.delve .
+
 .PHONY: build-image-boringcrypto
 build-image-boringcrypto: clean ## Build the rollout-operator image with boringcrypto 
 	# Tags with the regular image repo for integration testing
@@ -41,6 +54,10 @@ publish-images: publish-standard-image publish-boringcrypto-image ## Build and p
 publish-standard-image: clean ## Build and publish only the standard rollout-operator image
 	docker buildx build --push --platform linux/amd64,linux/arm64 --build-arg revision=$(GIT_REVISION) --build-arg BUILDTARGET=rollout-operator -t $(IMAGE_PREFIX)/rollout-operator:$(IMAGE_TAG) .
 
+.PHONY: publish-debug-image
+publish-debug-image: clean
+	docker buildx build --push --platform linux/amd64,linux/arm64 --build-arg revision=$(GIT_REVISION) --build-arg BUILDTARGET=rollout-operator-debug -t $(IMAGE_PREFIX)/rollout-operator:$(IMAGE_TAG_DEBUG) -f Dockerfile.delve .
+
 .PHONY: publish-boringcrypto-image
 publish-boringcrypto-image: clean ## Build and publish only the boring-crypto rollout-operator image
 	docker buildx build --push --platform linux/amd64,linux/arm64 --build-arg revision=$(GIT_REVISION) --build-arg BUILDTARGET=rollout-operator-boringcrypto -t $(IMAGE_PREFIX)/rollout-operator-boringcrypto:$(IMAGE_TAG) .