move tool download to script

BUILD.md

@@ -9,7 +9,7 @@ git clone --branch v2 https://github.com/aws/aws-node-termination-handler.git
 Install build tools
 
 ```sh
-make controller-gen ko envtest
+make toolchain
 ```
 
 Configure image repository location

src/Makefile

@@ -1,3 +1,8 @@
+PROJECT_DIR := $(shell dirname $(abspath $(lastword $(MAKEFILE_LIST))))
+CONTROLLER_GEN = $(PROJECT_DIR)/bin/controller-gen
+KO = $(PROJECT_DIR)/bin/ko
+ENVTEST = $(PROJECT_DIR)/bin/setup-envtest
+
 
 # Image URL to use all building/pushing image targets
 IMG ?= controller:latest
@@ -34,22 +39,26 @@ SHELL = /usr/bin/env bash -o pipefail
 help: ## Display this help.
 	@awk 'BEGIN {FS = ":.*##"; printf "\nUsage:\n  make \033[36m<target>\033[0m\n"} /^[a-zA-Z_0-9-]+:.*?##/ { printf "  \033[36m%-15s\033[0m %s\n", $$1, $$2 } /^##@/ { printf "\n\033[1m%s\033[0m\n", substr($$0, 5) } ' $(MAKEFILE_LIST)
 
+.PHONY: toolchain
+toolchain:  # Download additional tools.
+	@./scripts/toolchain.sh -d "$(PROJECT_DIR)/bin"
+
 ##@ Development
 
 .PHONY: manifests
-manifests: controller-gen ## Generate WebhookConfiguration, ClusterRole and CustomResourceDefinition objects.
+manifests:  # Generate WebhookConfiguration, ClusterRole and CustomResourceDefinition objects.
 	$(CONTROLLER_GEN) rbac:roleName=manager-role crd webhook paths="./..." output:crd:artifacts:config=config/crd/bases
 
 .PHONY: generate
-generate: controller-gen ## Generate code containing DeepCopy, DeepCopyInto, and DeepCopyObject method implementations.
+generate:  # Generate code containing DeepCopy, DeepCopyInto, and DeepCopyObject method implementations.
 	$(CONTROLLER_GEN) object:headerFile="hack/boilerplate.go.txt" paths="./..."
 
 .PHONY: fmt
-fmt: ## Run go fmt against code.
+fmt: # Run go fmt against code.
 	go fmt ./...
 
 .PHONY: vet
-vet: ## Run go vet against code.
+vet: # Run go vet against code.
 	go vet ./...
 
 .PHONY: test
@@ -74,32 +83,3 @@ apply:  # Deploy the controller into the current kubernetes cluster.
 .PHONY: delete
 delete:  # Delete controller from current kubernetes cluster.
 	helm uninstall dev --namespace nthv2
-
-CONTROLLER_GEN = $(shell pwd)/bin/controller-gen
-.PHONY: controller-gen
-controller-gen: ## Download controller-gen locally if necessary.
-	$(call go-get-tool,$(CONTROLLER_GEN),sigs.k8s.io/controller-tools/cmd/[email protected])
-
-KO = $(shell pwd)/bin/ko
-.PHONY: ko
-ko: ## Download ko locally if necessary.
-	$(call go-get-tool,$(KO),github.com/google/[email protected])
-
-ENVTEST = $(shell pwd)/bin/setup-envtest
-.PHONY: envtest
-envtest: ## Download envtest-setup locally if necessary.
-	$(call go-get-tool,$(ENVTEST),sigs.k8s.io/controller-runtime/tools/[email protected])
-
-# go-get-tool will 'go get' any package $2 and install it to $1.
-PROJECT_DIR := $(shell dirname $(abspath $(lastword $(MAKEFILE_LIST))))
-define go-get-tool
-@[ -f $(1) ] || { \
-set -e ;\
-TMP_DIR=$$(mktemp -d) ;\
-cd $$TMP_DIR ;\
-go mod init tmp ;\
-echo "Downloading $(2)" ;\
-GOBIN=$(PROJECT_DIR)/bin go get $(2) ;\
-rm -rf $$TMP_DIR ;\
-}
-endef

src/scripts/toolchain.sh

@@ -0,0 +1,52 @@
+#!/usr/bin/env bash
+
+set -euo pipefail
+
+usage=$(cat << EOM
+usage: $(basename "$0") -h | -d PATH
+
+    Download tools to PATH.
+
+    Arguments:
+        -h        Print usage message then exit.
+        -d PATH   Destination directory for downloaded tools.
+
+EOM
+)
+
+tools=(
+    "github.com/google/[email protected]"
+    "sigs.k8s.io/controller-tools/cmd/[email protected]"
+    # setup-envtest version specifiers:
+    #   https://pkg.go.dev/sigs.k8s.io/controller-runtime/tools/setup-envtest/versions?tab=versions
+    "sigs.k8s.io/controller-runtime/tools/[email protected]"
+)
+
+bin_dir=""
+
+while getopts "d:h" opt; do
+    case $opt in
+        d ) bin_dir="$OPTARG"
+            ;;
+        * ) echo "$usage" 1>&2
+            exit 1
+            ;;
+    esac
+done
+
+if [[ -z "$bin_dir" ]]; then
+    echo "error: missing destination path"
+    echo "$usage" 1>&2
+    exit 1
+fi
+
+tmp_dir="$(mktemp -d)"
+trap "rm -rf \"$tmp_dir\"" EXIT
+
+cd "$tmp_dir"
+go mod init tmp >/dev/null 2>&1
+
+for tool in ${tools[@]}; do
+    echo "Downloading $tool"
+    GOBIN="$bin_dir" go install "$tool"
+done