Golang : Add build version and other information in executables

Problem:

You want to add version and other information such as compilation time into your executables(binaries) and display the information during run time. How to do that?

Solution:

Displaying version and compilation time information during run time can be useful for testing and debugging purpose. For example, you are a developer producing different versions of executable for the testing team to test and having this sort of information can assist the test team in providing accurate feedback.

Below is a simple example of how to include version and compilation time information during compilation time.

---

 package main

 import (
 "fmt"
 "time"
 )

 var (
 version string
 timeStamp string
 )

 func main() {
 timeStamp := time.Now()

 fmt.Println("Running version : ", version)
 fmt.Println("Build time: ", timeStamp)
 }

---

and build this file with -ldflags flag

For example:

go build -ldflags "-X main.version=v1.1" buildinfo.go

when executing the binary, you will see this during run time:

$ ./buildinfo

Running version : v1.1

Build time: 2017-02-15 14:35:35.598182767 +0800 SGT

Hope this helps!

Happy coding!

NOTES:

If you encounter this error message during compilation time:

-X flag requires argument of the form importpath.name=value

simply change "-X main.version v0.1" to "-X main.version=v0.1"

References:

https://www.socketloop.com/tutorials/golang-get-local-time-and-equivalent-time-in-different-time-zone

https://www.socketloop.com/tutorials/golang-setting-variable-value-with-ldflags