manage git tag versioned releases

- cross-compile binary releases
- update installation instructions in README

.gitignore

@@ -27,3 +27,4 @@ _testmain.go
 
 mongodb_exporter
 vendor/
+release/

Makefile

@@ -1,3 +1,6 @@
+package = github.com/dcu/mongodb_exporter
+TAG := $(shell git tag | sort -r | head -n 1)
+
 test:
 	go test github.com/dcu/mongodb_exporter/collector -cover -coverprofile=collector_coverage.out -short
 	go tool cover -func=collector_coverage.out
@@ -11,3 +14,9 @@ deps:
 build: deps
 	go build mongodb_exporter.go
 
+release: deps
+	mkdir -p release
+	perl -p -i -e 's/{{VERSION}}/$(TAG)/g' mongodb_exporter.go
+	GOOS=darwin GOARCH=amd64 go build -o release/mongodb_exporter-darwin-amd64 $(package)
+	GOOS=linux GOARCH=amd64 go build -o release/mongodb_exporter-linux-amd64 $(package)
+	perl -p -i -e 's/$(TAG)/{{VERSION}}/g' mongodb_exporter.go

README.md

@@ -6,18 +6,13 @@ MongoDB exporter for prometheus.io, written in go.
 
 ## Installing
 
-Requires Go 1.5+
-
-Make sure $GOPATH/bin is in your $PATH, then:
-
-    go get -u github.com/dcu/mongodb_exporter
-    mongodb_exporter -h
+Download a [release](https://github.com/dcu/mongodb_exporter/releases)
 
 ## Building
 
 Requires [glide](https://github.com/Masterminds/glide) for dependency management
 
-    go get -u github.com/dcu/mongodb_exporter
+    git clone [email protected]:dcu/mongodb_exporter.git $GOPATH/src/github.com/dcu/mongodb_exporter
     cd $GOPATH/src/github.com/dcu/mongodb_exporter
     make build
     ./mongodb_exporter -h

mongodb_exporter.go

@@ -50,6 +50,7 @@ var (
 	mongodbCollectOplog                 = flag.Bool("mongodb.collect.oplog", true, "collect Mongodb Oplog status")
 	mongodbCollectReplSet               = flag.Bool("mongodb.collect.replset", true, "collect Mongodb replica set status")
 	mongodbCollectDatabaseMetrics       = flag.Bool("mongodb.collect.database", false, "collect MongoDB database metrics")
+	version                             = flag.Bool("version", false, "Print mongodb_exporter version")
 )
 
 type basicAuthHandler struct {
@@ -166,6 +167,10 @@ func createHTTPServerLogWrapper() *slog.Logger {
 
 func main() {
 	flag.Parse()
+	if *version {
+		fmt.Println("mongodb_exporter version: {{VERSION}}")
+		return
+	}
 	shared.ParseEnabledGroups(*enabledGroupsFlag)
 
 	startWebServer()