Convert to Go modules

* Update promu config.
* Convert to Go modules.
* Update vendoring.
* Update Makefile.common.
* Update circleci config.
* Use Prometheus release tar for promtool.

Signed-off-by: Ben Kochie <[email protected]>

.circleci/config.yml

@@ -1,16 +1,24 @@
 ---
 version: 2.1
 
-jobs:
-  test:
+executors:
+  # Whenever the Go version is updated here, .promu.yml should
+  # also be updated.
+  golang:
     docker:
     - image: circleci/golang:1.11
-    working_directory: /go/src/github.com/prometheus/node_exporter
+
+jobs:
+  test:
+    executor: golang
 
     steps:
     - checkout
     - run: make promu
     - run: make
+    - store_artifacts:
+        path: node_exporter
+        destination: /build/node_exporter
     - run: rm -v node_exporter
 
   codespell:
@@ -24,7 +32,6 @@ jobs:
 
   build:
     machine: true
-    working_directory: /home/circleci/.go_workspace/src/github.com/prometheus/node_exporter
 
     environment:
       DOCKER_TEST_IMAGE_NAME: quay.io/prometheus/golang-builder:1.11-base
@@ -33,12 +40,15 @@ jobs:
     steps:
     - checkout
     - run: make promu
-    - run: promu crossbuild -v --go 1.11
-    - run: promu --config .promu-cgo.yml crossbuild -v --go 1.11
+    - run: promu crossbuild
+    - run: promu --config .promu-cgo.yml crossbuild
     - persist_to_workspace:
         root: .
         paths:
         - .build
+    - store_artifacts:
+        path: .build
+        destination: /build
     - run: ln -s .build/linux-amd64/node_exporter node_exporter
     - run:
         command: |
@@ -58,9 +68,7 @@ jobs:
           fi
 
   docker_hub_master:
-    docker:
-    - image: circleci/golang:1.11
-    working_directory: /go/src/github.com/prometheus/node_exporter
+    executor: golang
 
     steps:
     - checkout
@@ -77,9 +85,7 @@ jobs:
     - run: make docker-publish DOCKER_REPO=quay.io/prometheus
 
   docker_hub_release_tags:
-    docker:
-    - image: circleci/golang:1.11
-    working_directory: /go/src/github.com/prometheus/node_exporter
+    executor: golang
 
     steps:
     - checkout

.promu-cgo.yml

@@ -5,13 +5,13 @@ repository:
 build:
     binaries:
         - name: node_exporter
-    flags: -a -tags 'netgo static_build'
+    flags: -mod=vendor -a -tags 'netgo static_build'
     ldflags: |
-        -X {{repoPath}}/vendor/github.com/prometheus/common/version.Version={{.Version}}
-        -X {{repoPath}}/vendor/github.com/prometheus/common/version.Revision={{.Revision}}
-        -X {{repoPath}}/vendor/github.com/prometheus/common/version.Branch={{.Branch}}
-        -X {{repoPath}}/vendor/github.com/prometheus/common/version.BuildUser={{user}}@{{host}}
-        -X {{repoPath}}/vendor/github.com/prometheus/common/version.BuildDate={{date "20060102-15:04:05"}}
+        -X github.com/prometheus/common/version.Version={{.Version}}
+        -X github.com/prometheus/common/version.Revision={{.Revision}}
+        -X github.com/prometheus/common/version.Branch={{.Branch}}
+        -X github.com/prometheus/common/version.BuildUser={{user}}@{{host}}
+        -X github.com/prometheus/common/version.BuildDate={{date "20060102-15:04:05"}}
 tarball:
     files:
         - LICENSE

.promu.yml

@@ -3,13 +3,13 @@ repository:
 build:
     binaries:
         - name: node_exporter
-    flags: -a -tags 'netgo static_build'
+    flags: -mod=vendor -a -tags 'netgo static_build'
     ldflags: |
-        -X {{repoPath}}/vendor/github.com/prometheus/common/version.Version={{.Version}}
-        -X {{repoPath}}/vendor/github.com/prometheus/common/version.Revision={{.Revision}}
-        -X {{repoPath}}/vendor/github.com/prometheus/common/version.Branch={{.Branch}}
-        -X {{repoPath}}/vendor/github.com/prometheus/common/version.BuildUser={{user}}@{{host}}
-        -X {{repoPath}}/vendor/github.com/prometheus/common/version.BuildDate={{date "20060102-15:04:05"}}
+        -X github.com/prometheus/common/version.Version={{.Version}}
+        -X github.com/prometheus/common/version.Revision={{.Revision}}
+        -X github.com/prometheus/common/version.Branch={{.Branch}}
+        -X github.com/prometheus/common/version.BuildUser={{user}}@{{host}}
+        -X github.com/prometheus/common/version.BuildDate={{date "20060102-15:04:05"}}
 tarball:
     files:
         - LICENSE

Makefile

@@ -17,7 +17,9 @@ GO     ?= GO15VENDOREXPERIMENT=1 go
 GOARCH := $(shell $(GO) env GOARCH)
 GOHOSTARCH := $(shell $(GO) env GOHOSTARCH)
 
-PROMTOOL    ?= $(FIRST_GOPATH)/bin/promtool
+PROMTOOL_VERSION ?= 2.5.0
+PROMTOOL_URL     ?= https://github.com/prometheus/prometheus/releases/download/v$(PROMTOOL_VERSION)/prometheus-$(PROMTOOL_VERSION).$(GO_BUILD_PLATFORM).tar.gz
+PROMTOOL         ?= $(FIRST_GOPATH)/bin/promtool
 
 DOCKER_IMAGE_NAME       ?= node-exporter
 MACH                    ?= $(shell uname -m)
@@ -139,6 +141,12 @@ test-docker:
 	@echo ">> testing docker image"
 	./test_image.sh "$(DOCKER_REPO)/$(DOCKER_IMAGE_NAME):$(DOCKER_IMAGE_TAG)" 9100
 
-.PHONY: promtool $(FIRST_GOPATH)/bin/promtool
-$(FIRST_GOPATH)/bin/promtool promtool:
-	@GOOS= GOARCH= $(GO) get -u github.com/prometheus/prometheus/cmd/promtool
+.PHONY: promtool
+promtool: $(PROMTOOL)
+
+.PHONY: $(PROMTOOL)
+$(PROMTOOL):
+	curl -s -L $(PROMTOOL_URL) | tar -xvz -C /tmp
+	mkdir -v -p $(FIRST_GOPATH)/bin
+	cp -v /tmp/prometheus-$(PROMTOOL_VERSION).$(GO_BUILD_PLATFORM)/promtool $(FIRST_GOPATH)/bin/promtool
+

Makefile.common

@@ -16,7 +16,7 @@
 # !!! Open PRs only against the prometheus/prometheus/Makefile.common repository!
 
 # Example usage :
-# Create the main Makefile in the root project directory. 
+# Create the main Makefile in the root project directory.
 # include Makefile.common
 # customTarget:
 # 	@echo ">> Running customTarget"
@@ -28,18 +28,53 @@ 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
-GOVENDOR     := $(FIRST_GOPATH)/bin/govendor
 pkgs          = ./...
 
+GO_VERSION        ?= $(shell $(GO) version)
+GO_BUILD_PLATFORM ?= $(subst /,-,$(lastword $(GO_VERSION)))
+
+PROMU_VERSION ?= 0.2.0
+PROMU_URL     := https://github.com/prometheus/promu/releases/download/v$(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: style staticcheck unused build test
+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
@@ -49,7 +84,12 @@ all: style staticcheck unused build test
 .PHONY: common-style
 common-style:
 	@echo ">> checking code style"
-	! $(GOFMT) -d $$(find . -path ./vendor -prune -o -name '*.go' -print) | grep '^'
+	@fmtRes=$$($(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:
@@ -65,37 +105,54 @@ common-check_license:
 .PHONY: common-test-short
 common-test-short:
 	@echo ">> running short tests"
-	$(GO) test -short $(pkgs)
+	GO111MODULE=$(GO111MODULE) $(GO) test -short $(GOOPTS) $(pkgs)
 
 .PHONY: common-test
 common-test:
 	@echo ">> running all tests"
-	$(GO) test -race $(pkgs)
+	GO111MODULE=$(GO111MODULE) $(GO) test -race $(GOOPTS) $(pkgs)
 
 .PHONY: common-format
 common-format:
 	@echo ">> formatting code"
-	$(GO) fmt $(pkgs)
+	GO111MODULE=$(GO111MODULE) $(GO) fmt $(GOOPTS) $(pkgs)
 
 .PHONY: common-vet
 common-vet:
 	@echo ">> vetting code"
-	$(GO) vet $(pkgs)
+	GO111MODULE=$(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"
-	$(PROMU) build --prefix $(PREFIX)
+	GO111MODULE=$(GO111MODULE) $(PROMU) build --prefix $(PREFIX)
 
 .PHONY: common-tarball
 common-tarball: promu
@@ -115,13 +172,52 @@ common-docker-tag-latest:
 	docker tag "$(DOCKER_REPO)/$(DOCKER_IMAGE_NAME):$(DOCKER_IMAGE_TAG)" "$(DOCKER_REPO)/$(DOCKER_IMAGE_NAME):latest"
 
 .PHONY: promu
-promu:
-	GOOS= GOARCH= $(GO) get -u github.com/prometheus/promu
+promu: $(PROMU)
+
+$(PROMU):
+	curl -s -L $(PROMU_URL) | tar -xvz -C /tmp
+	mkdir -v -p $(FIRST_GOPATH)/bin
+	cp -v /tmp/promu-$(PROMU_VERSION).$(GO_BUILD_PLATFORM)/promu $(FIRST_GOPATH)/bin/promu
+
+.PHONY: proto
+proto:
+	@echo ">> generating code from proto files"
+	@./scripts/genproto.sh
 
 .PHONY: $(STATICCHECK)
 $(STATICCHECK):
-	GOOS= GOARCH= $(GO) get -u honnef.co/go/tools/cmd/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

go.mod

@@ -0,0 +1,32 @@
+module github.com/prometheus/node_exporter
+
+require (
+	github.com/alecthomas/template v0.0.0-20160405071501-a0175ee3bccc // indirect
+	github.com/alecthomas/units v0.0.0-20151022065526-2efee857e7cf // indirect
+	github.com/beevik/ntp v0.2.0
+	github.com/beorn7/perks v0.0.0-20180321164747-3a771d992973 // indirect
+	github.com/coreos/go-systemd v0.0.0-20180511133405-39ca1b05acc7
+	github.com/ema/qdisc v0.0.0-20180104102928-b307c22d3ce7
+	github.com/godbus/dbus v4.1.0+incompatible
+	github.com/gogo/protobuf v1.1.1 // indirect
+	github.com/golang/protobuf v1.2.0 // indirect
+	github.com/google/go-cmp v0.2.0 // indirect
+	github.com/konsorten/go-windows-terminal-sequences v1.0.1 // indirect
+	github.com/lufia/iostat v0.0.0-20170605150913-9f7362b77ad3
+	github.com/mattn/go-xmlrpc v0.0.0-20180913190254-6e944673e4c0
+	github.com/matttproud/golang_protobuf_extensions v1.0.1 // indirect
+	github.com/mdlayher/genetlink v0.0.0-20180917171408-7615bc153978 // indirect
+	github.com/mdlayher/netlink v0.0.0-20180920202405-794849f2d5bf // indirect
+	github.com/mdlayher/wifi v0.0.0-20180727163819-efdf3f4195d9
+	github.com/prometheus/client_golang v0.9.1
+	github.com/prometheus/client_model v0.0.0-20180712105110-5c3871d89910
+	github.com/prometheus/common v0.0.0-20181015124227-bcb74de08d37
+	github.com/prometheus/procfs v0.0.0-20181005140218-185b4288413d
+	github.com/sirupsen/logrus v1.1.1 // indirect
+	github.com/soundcloud/go-runit v0.0.0-20150630195641-06ad41a06c4a
+	golang.org/x/crypto v0.0.0-20181009213950-7c1a557ab941 // indirect
+	golang.org/x/net v0.0.0-20181005035420-146acd28ed58 // indirect
+	golang.org/x/sync v0.0.0-20181108010431-42b317875d0f // indirect
+	golang.org/x/sys v0.0.0-20181005133103-4497e2df6f9e
+	gopkg.in/alecthomas/kingpin.v2 v2.2.6
+)