warren/cmd_build.go

package main

import (
	"fmt"
	"log"
	"os"
	"os/exec"
	"strings"
	"time"
)

var buildUsage = `
warren build - Runs go build and populates the following variables:

  Build.GitBranch	from git
  Build.GitHash		from git
  Build.Date		from system time
`

var buildCmd = &Command{
	Name:    "build",
	Usage:   "",
	Summary: "build the go server in the current directory",
	Help:    buildUsage,
	Run:     buildRun,
}

func buildRun(cmd *Command, args ...string) {
	if len(args) > 0 && args[0] == "help" {
		fmt.Print(cmd.Help)
		return
	}

	githash, err := exec.Command("git", "rev-parse", "HEAD").Output()
	if err != nil {
		log.Fatal(err)
	}
	gitbranchb, err := exec.Command("git", "rev-parse", "--abbrev-ref", "HEAD").Output()
	if err != nil {
		log.Fatal(err)
	}
	gitbranch := strings.TrimSpace(string(gitbranchb))
	date := time.Now().Format(time.RFC3339)
	gobuild := exec.Command("go", "build", "-ldflags", fmt.Sprintf("-X main.Build.Date %s -X main.Build.GitHash %s -X main.Build.GitBranch %s\"", date, githash, gitbranch))
	gobuild.Stderr = os.Stderr
	gobuild.Stdout = os.Stdout
	err = gobuild.Run()
	if err != nil {
		log.Fatal(err)
	}
}