# Copyright 2018 The Prometheus Authors
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.


# A common Makefile that includes rules to be reused in different prometheus projects.
# !!! Open PRs only against the prometheus/prometheus/Makefile.common repository!

# Example usage :
# Create the main Makefile in the root project directory.
# include Makefile.common
# customTarget:
# 	@echo ">> Running customTarget"
#

# Ensure GOBIN is not set during build so that promu is installed to the correct path
unexport GOBIN

GO           ?= go
GOFMT        ?= $(GO)fmt
FIRST_GOPATH := $(firstword $(subst :, ,$(shell $(GO) env GOPATH)))
GOOPTS       ?=

GO_VERSION        ?= $(shell $(GO) version)
GO_VERSION_NUMBER ?= $(word 3, $(GO_VERSION))
PRE_GO_111        ?= $(shell echo $(GO_VERSION_NUMBER) | grep -E 'go1\.(10|[0-9])\.')

unexport GOVENDOR
ifeq (, $(PRE_GO_111))
	ifneq (,$(wildcard go.mod))
		# Enforce Go modules support just in case the directory is inside GOPATH (and for Travis CI).
		GO111MODULE := on

		ifneq (,$(wildcard vendor))
			# Always use the local vendor/ directory to satisfy the dependencies.
			GOOPTS := $(GOOPTS) -mod=vendor
		endif
	endif
else
	ifneq (,$(wildcard go.mod))
		ifneq (,$(wildcard vendor))
$(warning This repository requires Go >= 1.11 because of Go modules)
$(warning Some recipes may not work as expected as the current Go runtime is '$(GO_VERSION_NUMBER)')
		endif
	else
		# This repository isn't using Go modules (yet).
		GOVENDOR := $(FIRST_GOPATH)/bin/govendor
	endif

	unexport GO111MODULE
endif
PROMU        := $(FIRST_GOPATH)/bin/promu
STATICCHECK  := $(FIRST_GOPATH)/bin/staticcheck
pkgs          = ./...

GOHOSTOS ?= $(shell $(GO) env GOHOSTOS)
GOHOSTARCH ?= $(shell $(GO) env GOHOSTARCH)
ifeq (arm, $(GOHOSTARCH))
	GOHOSTARM ?= $(shell GOARM= $(GO) env GOARM)
	GO_BUILD_PLATFORM ?= $(GOHOSTOS)-$(GOHOSTARCH)v$(GOHOSTARM)
else
	GO_BUILD_PLATFORM ?= $(GOHOSTOS)-$(GOHOSTARCH)
endif

PROMU_VERSION ?= 0.2.0
PROMU_URL     := https://github.com/prometheus/promu/releases/download/v$(PROMU_VERSION)/promu-$(PROMU_VERSION).$(GO_BUILD_PLATFORM).tar.gz

PREFIX                  ?= $(shell pwd)
BIN_DIR                 ?= $(shell pwd)
DOCKER_IMAGE_TAG        ?= $(subst /,-,$(shell git rev-parse --abbrev-ref HEAD))
DOCKER_REPO             ?= prom

.PHONY: all
all: precheck style staticcheck unused build test

# This rule is used to forward a target like "build" to "common-build".  This
# allows a new "build" target to be defined in a Makefile which includes this
# one and override "common-build" without override warnings.
%: common-% ;

.PHONY: common-style
common-style:
	@echo ">> checking code style"
	@fmtRes=$$($(GOFMT) -d $$(find . -path ./vendor -prune -o -name '*.go' -print)); \
	if [ -n "$${fmtRes}" ]; then \
		echo "gofmt checking failed!"; echo "$${fmtRes}"; echo; \
		echo "Please ensure you are using $$($(GO) version) for formatting code."; \
		exit 1; \
	fi

.PHONY: common-check_license
common-check_license:
	@echo ">> checking license header"
	@licRes=$$(for file in $$(find . -type f -iname '*.go' ! -path './vendor/*') ; do \
               awk 'NR<=3' $$file | grep -Eq "(Copyright|generated|GENERATED)" || echo $$file; \
       done); \
       if [ -n "$${licRes}" ]; then \
               echo "license header checking failed:"; echo "$${licRes}"; \
               exit 1; \
       fi

.PHONY: common-test-short
common-test-short:
	@echo ">> running short tests"
	GO111MODULE=$(GO111MODULE) $(GO) test -short $(GOOPTS) $(pkgs)

.PHONY: common-test
common-test:
	@echo ">> running all tests"
	GO111MODULE=$(GO111MODULE) $(GO) test -race $(GOOPTS) $(pkgs)

.PHONY: common-format
common-format:
	@echo ">> formatting code"
	GO111MODULE=$(GO111MODULE) $(GO) fmt $(pkgs)

.PHONY: common-vet
common-vet:
	@echo ">> vetting code"
	GO111MODULE=$(GO111MODULE) $(GO) vet $(GOOPTS) $(pkgs)

.PHONY: common-staticcheck
common-staticcheck: $(STATICCHECK)
	@echo ">> running staticcheck"
ifdef GO111MODULE
	GO111MODULE=$(GO111MODULE) $(STATICCHECK) -ignore "$(STATICCHECK_IGNORE)" -checks "SA*" $(pkgs)
else
	$(STATICCHECK) -ignore "$(STATICCHECK_IGNORE)" $(pkgs)
endif

.PHONY: common-unused
common-unused: $(GOVENDOR)
ifdef GOVENDOR
	@echo ">> running check for unused packages"
	@$(GOVENDOR) list +unused | grep . && exit 1 || echo 'No unused packages'
else
ifdef GO111MODULE
	@echo ">> running check for unused/missing packages in go.mod"
	GO111MODULE=$(GO111MODULE) $(GO) mod tidy
	@git diff --exit-code -- go.sum go.mod
ifneq (,$(wildcard vendor))
	@echo ">> running check for unused packages in vendor/"
	GO111MODULE=$(GO111MODULE) $(GO) mod vendor
	@git diff --exit-code -- go.sum go.mod vendor/
endif
endif
endif

.PHONY: common-build
common-build: promu
	@echo ">> building binaries"
	GO111MODULE=$(GO111MODULE) $(PROMU) build --prefix $(PREFIX)

.PHONY: common-tarball
common-tarball: promu
	@echo ">> building release tarball"
	$(PROMU) tarball --prefix $(PREFIX) $(BIN_DIR)

.PHONY: common-docker
common-docker:
	docker build -t "$(DOCKER_REPO)/$(DOCKER_IMAGE_NAME):$(DOCKER_IMAGE_TAG)" .

.PHONY: common-docker-publish
common-docker-publish:
	docker push "$(DOCKER_REPO)/$(DOCKER_IMAGE_NAME)"

.PHONY: common-docker-tag-latest
common-docker-tag-latest:
	docker tag "$(DOCKER_REPO)/$(DOCKER_IMAGE_NAME):$(DOCKER_IMAGE_TAG)" "$(DOCKER_REPO)/$(DOCKER_IMAGE_NAME):latest"

.PHONY: promu
promu: $(PROMU)

$(PROMU):
	$(eval PROMU_TMP := $(shell mktemp -d))
	curl -s -L $(PROMU_URL) | tar -xvzf - -C $(PROMU_TMP)
	mkdir -p $(FIRST_GOPATH)/bin
	cp $(PROMU_TMP)/promu-$(PROMU_VERSION).$(GO_BUILD_PLATFORM)/promu $(FIRST_GOPATH)/bin/promu
	rm -r $(PROMU_TMP)

.PHONY: proto
proto:
	@echo ">> generating code from proto files"
	@./scripts/genproto.sh

.PHONY: $(STATICCHECK)
$(STATICCHECK):
ifdef GO111MODULE
# Get staticcheck from a temporary directory to avoid modifying the local go.{mod,sum}.
# See https://github.com/golang/go/issues/27643.
# For now, we are using the next branch of staticcheck because master isn't compatible yet with Go modules.
	tmpModule=$$(mktemp -d 2>&1) && \
	mkdir -p $${tmpModule}/staticcheck && \
	cd "$${tmpModule}"/staticcheck && \
	GO111MODULE=on $(GO) mod init example.com/staticcheck && \
	GO111MODULE=on GOOS= GOARCH= $(GO) get -u honnef.co/go/tools/cmd/staticcheck@next && \
	rm -rf $${tmpModule};
else
	GOOS= GOARCH= GO111MODULE=off $(GO) get -u honnef.co/go/tools/cmd/staticcheck
endif

ifdef GOVENDOR
.PHONY: $(GOVENDOR)
$(GOVENDOR):
	GOOS= GOARCH= $(GO) get -u github.com/kardianos/govendor
endif

.PHONY: precheck
precheck::

define PRECHECK_COMMAND_template =
precheck:: $(1)_precheck


PRECHECK_COMMAND_$(1) ?= $(1) $$(strip $$(PRECHECK_OPTIONS_$(1)))
.PHONY: $(1)_precheck
$(1)_precheck:
	@if ! $$(PRECHECK_COMMAND_$(1)) 1>/dev/null 2>&1; then \
		echo "Execution of '$$(PRECHECK_COMMAND_$(1))' command failed. Is $(1) installed?"; \
		exit 1; \
	fi
endef