Include the last Git Commit in the output of your Go program version

const Major = "1"
const Minor = "2"
const Fix = "1"
const Verbal = "TBB Training Ledger - HTTPS"

var versionCmd = &cobra.Command{
   Use:   "version",
   Short: "Describes version.",
   Run: func(cmd *cobra.Command, args []string) {
      fmt.Println(fmt.Sprintf("Version: %s.%s.%s-alpha %s", Major, Minor, Fix, Verbal))
   },
}

$ tbb version
Version: 1.2.1-alpha TBB Training Ledger - HTTPS

// Configured via -ldflags during build
var GitCommit string

var versionCmd = &cobra.Command{
   Use:   "version",
   Short: "Describes version.",
   Run: func(cmd *cobra.Command, args []string) {
      fmt.Println(fmt.Sprintf("Version: %s.%s.%s-alpha %s %s", Major, Minor, Fix, shortGitCommit(GitCommit), Verbal))
   },
}

// Bonus, shorten the git commit to first 6 chars for readability
func shortGitCommit(fullGitCommit string) string {
   shortCommit := ""
   if len(fullGitCommit) >= 6 {
      shortCommit = fullGitCommit[0:6]
   }

   return shortCommit
}

Step 2)

Add two new variables into your Makefile:

• GIT_COMMIT populated with latest commit using the git rev-list command, listing commit objects in reverse chronological order
• LDFLAGS with instructions to pass the GIT_COMMIT into the main.GitCommit var

And pass the GitCommit argument into your program using the ldflags on make build:

GIT_COMMIT:=$(shell git rev-list -1 HEAD)
LDFLAGS:=-X main.GitCommit=${GIT_COMMIT}

install:
   go install -ldflags "$(LDFLAGS)" ./...

$ make install
> go install -ldflags "-X main.GitCommit=ed441aee39e11...160" ./...

$ tbb version
> Version: 1.2.1-alpha ed441a TBB Training Ledger - HTTPS