SANDBOX-1561 | feature: debug builds for the host operator

build/Dockerfile.debug

@@ -0,0 +1,53 @@
+# Compile Delve in an intermediate step.
+FROM registry.access.redhat.com/ubi8/ubi:latest AS delve-builder
+
+# The Golang version must be provided as a build arguments, which will ensure
+# that Delve gets built with the same version the service's binary gets built
+# with, to avoid any discrepancies.
+ARG GOLANG_VERSION
+
+# Install Tar to be able to extract Golang.
+RUN yum install --assumeyes \
+    tar \
+    && yum clean all
+
+# Download and extract Golang.
+RUN curl --location --output "${GOLANG_VERSION}.linux-amd64.tar.gz" "https://go.dev/dl/${GOLANG_VERSION}.linux-amd64.tar.gz" \
+    && tar --directory /usr/local --extract --file "${GOLANG_VERSION}.linux-amd64.tar.gz" \
+    && rm --force "${GOLANG_VERSION}.linux-amd64.tar.gz"
+
+# Put Golang in the path so that we can Delve with it.
+ENV PATH=$PATH:/usr/local/go/bin
+
+# Build Delve and leave it in a temporary directory.
+RUN GOBIN=/tmp/bin go install github.com/go-delve/delve/cmd/dlv@latest
+
+# Build the operator as normal.
+FROM registry.access.redhat.com/ubi8/ubi-minimal:latest
+
+LABEL maintainer = "KubeSaw <[email protected]>"
+LABEL author = "KubeSaw <[email protected]>"
+
+# Ensure that the "DEBUG_MODE" is enabled so that the binary executes with
+# Delve.
+ENV DEBUG_MODE=true \
+    OPERATOR=/usr/local/bin/host-operator \
+    USER_UID=1001 \
+    USER_NAME=host-operator \
+    LANG=en_US.utf8
+
+# Install operator binary in the image.
+COPY build/_output/bin/host-operator ${OPERATOR}
+
+COPY build/bin /usr/local/bin
+RUN  /usr/local/bin/user_setup
+
+# Copy Delve to the image so that we can execute the operator with it.
+COPY --from=delve-builder /tmp/bin/dlv /usr/local/bin/dlv
+
+ENTRYPOINT ["/usr/local/bin/entrypoint"]
+
+# Expose the debugger's port.
+EXPOSE 50000
+
+USER ${USER_UID}

build/bin/entrypoint

@@ -9,4 +9,9 @@ if ! whoami &>/dev/null; then
   fi
 fi
 
-exec ${OPERATOR} $@
+if [ -n "${DEBUG_MODE}" ]
+then
+  exec /usr/local/bin/dlv --listen=:50000 --headless --continue --api-version=2 --accept-multiclient exec "${OPERATOR}" "$@"
+else
+  exec ${OPERATOR} "$@"
+fi

controllers/toolchainconfig/env.go

@@ -1,3 +1,6 @@
 package toolchainconfig
 
-const RegistrationServiceImageEnvKey = "REGISTRATION_SERVICE_IMAGE"
+const (
+	RegistrationServiceImageEnvKey   = "REGISTRATION_SERVICE_IMAGE"
+	RegistrationServiceCommandEnvKey = "REGISTRATION_SERVICE_COMMAND"
+)

controllers/toolchainconfig/toolchainconfig_controller.go

@@ -151,6 +151,16 @@ func getVars(namespace string, cfg ToolchainConfig) templateVars {
 	vars["IMAGE"] = image
 	vars.addIfNotEmpty("NAMESPACE", namespace)
 	vars.addIfNotEmpty("REPLICAS", fmt.Sprint(cfg.RegistrationService().Replicas()))
+
+	// Allow overriding the registration service's command via an environment
+	// variable.
+	command := os.Getenv(RegistrationServiceCommandEnvKey)
+	if command != "" {
+		vars["COMMAND"] = command
+	} else {
+		vars["COMMAND"] = `["registration-service"]`
+	}
+
 	return vars
 }
 

deploy/templates/registration-service/registration-service.yaml

@@ -96,13 +96,12 @@ objects:
               image: ${IMAGE}
               ports:
                 - containerPort: 8080 # registration service
-                - containerPort: 8081 # proxy 
+                - containerPort: 8081 # proxy
                 - containerPort: 8082 # proxy metrics
                   name: metrics
                 - containerPort: 8083 # registration service metrics
                   name: regsvc-metrics
-              command:
-                - registration-service
+              command: ${{COMMAND}}
               imagePullPolicy: IfNotPresent
               livenessProbe:
                 failureThreshold: 3
@@ -141,7 +140,7 @@ objects:
                 requests:
                   cpu: "50m"
                   memory: "100M"
-  
+
   # route for the registration service
   - kind: Route
     apiVersion: v1
@@ -202,7 +201,7 @@ objects:
         run: registration-service
       type: ClusterIP
       sessionAffinity: null
-  
+
   # route for the proxy
   - kind: Route
     apiVersion: v1
@@ -224,7 +223,7 @@ objects:
       tls:
         termination: edge
       wildcardPolicy: None
- 
+
   # service associated with the proxy route
   - kind: Service
     apiVersion: v1
@@ -244,7 +243,7 @@ objects:
         run: registration-service
       type: ClusterIP
       sessionAffinity: null
-  
+
   # internal service for the proxy, used by Prometheus to scrape the metrics
   - kind: Service
     apiVersion: v1
@@ -271,3 +270,5 @@ parameters:
     value: quay.io/openshiftio/codeready-toolchain/registration-service:latest
   - name: REPLICAS
     value: '3'
+  - name: COMMAND
+    value: '["registration-service"]'

make/go.mk

@@ -20,6 +20,19 @@ $(OUT_DIR)/operator:
 		-o $(OUT_DIR)/bin/host-operator \
 		./cmd/main.go
 
+.PHONY: build-debug
+## Build the operator without the optimizations and the inlining, to enable
+## remote debugging via Delve.
+build-debug: generate
+	@echo "building host-operator in ${GO_PACKAGE_PATH}"
+	$(Q)go version
+	$(Q)CGO_ENABLED=0 GOARCH=${goarch} GOOS=linux \
+		go build ${V_FLAG} \
+		-gcflags "all=-N -l" \
+		-ldflags "-X ${GO_PACKAGE_PATH}/version.Commit=${GIT_COMMIT_ID} -X ${GO_PACKAGE_PATH}/version.BuildTime=${BUILD_TIME}" \
+		-o $(OUT_DIR)/bin/host-operator \
+		./cmd/main.go
+
 .PHONY: vendor
 vendor:
 	$(Q)go mod vendor

make/podman.mk

@@ -10,11 +10,21 @@ IMAGE_PLATFORM ?= linux/amd64
 podman-image: build
 	$(Q)podman build --platform ${IMAGE_PLATFORM} -f build/Dockerfile -t ${IMAGE} .
 
+## Build the operator's image with Delve on it so that it is ready to attach a
+## debugger to it.
+podman-image-debug: build-debug
+	$(Q) podman build --platform ${IMAGE_PLATFORM} --build-arg GOLANG_VERSION="$$(go version | awk '{print $$3}')" --file build/Dockerfile.debug --tag ${IMAGE} .
+
 .PHONY: podman-push
 ## Push the binary image to quay.io registry
 podman-push: check-namespace podman-image
 	$(Q)podman push ${IMAGE}
 
+.PHONY: podman-push-debug
+## Push the image with the debugger in it to the repository.
+podman-push-debug: check-namespace podman-image-debug
+	$(Q)podman push ${IMAGE}
+
 .PHONY: check-namespace
 check-namespace:
 ifeq ($(QUAY_NAMESPACE),${GO_PACKAGE_ORG_NAME})