Golang build ldflags

build.sh

GIT_TAG="$( git describe --abbrev=0 )"
GIT_HASH="$( git rev-parse HEAD )"
BUILD_DATE="$( date +%F )"  # Note: An ldflag cannot contain whitespace

REPO="github.com/user/repo"
OUTPUT_NAME="build-artifact"
PACKAGE="main.go"

read -r -d '' LDFLAGS << EOM
  -X ${REPO}/cmd.gitVersionTag=${GIT_TAG}
  -X ${REPO}/cmd.gitHash=${GIT_HASH}
  -X ${REPO}/cmd.buildDate=${BUILD_DATE}
EOM

go build -ldflags "${LDFLAGS}" \
  -o "${GOPATH}/bin/${OUTPUT_NAME}" "${PACKAGE}"

version.go

package cmd

import (
	"fmt"

	"github.com/spf13/cobra"
)

var gitHash, gitVersionTag, buildDate string

// versionCmd represents the version command
var versionCmd = &cobra.Command{
	Use:   "version",
	Short: "Display version",
	Run: func(cmd *cobra.Command, args []string) {
		fmt.Printf("version: %s\n", gitVersionTag)
		fmt.Printf("hash: %s\n", gitHash)
		fmt.Printf("build date: %s\n", buildDate)
	},
}

func init() {
	rootCmd.AddCommand(versionCmd)
}