= Go Version

image::https://travis-ci.org/christopherhein/go-version.svg?branch=master[link="https://travis-ci.org/christopherhein/go-version"]

This package gives allows you to use https://github.com/spf13/cobra and
https://github.com/goreleaser/goreleaser together to output your version in a
simple way. Supporting multiple flags for mutating the output.

== Usage

To use this package you will need to create `cobra` command for version such as
this.

[source,go]
----
package main

import (
	"fmt"
	goversion "go.hein.dev/go-version"
	"github.com/spf13/cobra"
)

var (
	shortened  = false
	version    = "dev"
	commit     = "none"
	date       = "unknown"
	output     = "json"
	versionCmd = &cobra.Command{
		Use:   "version",
		Short: "Version will output the current build information",
		Long:  ``,
		Run: func(_ *cobra.Command, _ []string) {
			resp := goVersion.FuncWithOutput(shortened, version, commit, date, output)
			fmt.Print(resp)
			return
		},
	}
)

func init() {
	versionCmd.Flags().BoolVarP(&shortened, "short", "s", false, "Print just the version number.")
	versionCmd.Flags().StringVarP(&output, "output", "o", "json", "Output format. One of 'yaml' or 'json'.")
	rootCmd.AddCommand(versionCmd)
}
----

When you do this then you can pass in these flags at build time. _If you'd like
more control of the output you can change the `Run` function to something more
like this.

[source,go]
----
Run: func(_ *cobra.Command, _ []string) {
	var response string
	versionOutput := New(version, commit, date)

	if shortened {
		response = versionOutput.ToShortened()
	} else {
		response = versionOutput.ToJSON()
	}
	fmt.Printf("%+v", response)
	return
},
----

[source,shell]
----
go build -ldflags "-X main.commit=<SOMEHASH> -X main.date=<SOMEDATE>"
----

This then gives your CLI the ability to use this for the JSON output:

[source,shell]
----
$ ./my-cli version
{"Version":"dev","Commit":"<SOMEHASH>","Date":"<SOMEDATE>"}
----

Or to make this human readable you could use:

[source,shell]
----
$ ./my-cli -s

Version: dev
Commit: <SOMEHASH>
Date: <SOMEDATE>
----

== Testing

To run the test suite all you need to do is run.

[source,shell]
----
go test -v ./...
----

== Contributing

If you want to contribute check out
https://github.com/christopherhein/go-version/blob/master/CONTRIBUTING.adoc