Add version command to print version info

README.md

@@ -49,6 +49,11 @@ cd cmd/boringproxy
 go build
 ```
 
+To build with version information:
+```bash
+go build -ldflags "-X main.Version=$(git describe --tags)"
+```
+
 Give the executable permission to bind low ports (ie 80/443):
 
 ```bash

cmd/boringproxy/main.go

@@ -12,12 +12,15 @@ import (
 const usage = `Usage: %s [command] [flags]
 
 Commands:
+    version      Prints version information.
     server       Start a new server.
     client       Connect to a server.
 
 Use "%[1]s command -h" for a list of flags for the command.
 `
 
+var Version string
+
 func fail(msg string) {
 	fmt.Fprintln(os.Stderr, msg)
 	os.Exit(1)
@@ -33,6 +36,8 @@ func main() {
 	command := os.Args[1]
 
 	switch command {
+	case "version":
+		fmt.Println(Version)
 	case "help", "-h", "--help", "-help":
 		fmt.Printf(usage, os.Args[0])
 	case "server":

scripts/build_arch.sh

@@ -1,4 +1,4 @@
 #!/bin/bash
 
 echo Building platform $1-$2
-CGO_ENABLED=0 GOOS=$1 GOARCH=$2 go build -o build/boringproxy-$1-$2$3
+CGO_ENABLED=0 GOOS=$1 GOARCH=$2 go build -ldflags "-X main.Version=$(git describe --tags)" -o build/boringproxy-$1-$2$3

scripts/build_x86_64.sh

@@ -1,4 +1,4 @@
 #!/bin/bash
 
 echo Building platform $1-x86_64
-CGO_ENABLED=0 GOOS=$1 GOARCH=amd64 go build -o build/boringproxy-$1-x86_64$2
+CGO_ENABLED=0 GOOS=$1 GOARCH=amd64 go build -ldflags "-X main.Version=$(git describe --tags)" -o build/boringproxy-$1-x86_64$2