feat(info): Added version subcommand

demeter version now shows you the build version and release date

cmd/root.go

@@ -83,9 +83,20 @@ retrieving books in epub format that are not in your local library.`,
 	},
 }
 
+// Info holds info related to the build process
+type Info struct {
+	Version string
+	Commit  string
+	Date    string
+	BuiltBy string
+}
+
+var info Info
+
 // Execute adds all child commands to the root command and sets flags appropriately.
 // This is called by main.main(). It only needs to happen once to the rootCmd.
-func Execute() {
+func Execute(in Info) {
+	info = in
 	if err := rootCmd.Execute(); err != nil {
 		fmt.Println(err)
 		os.Exit(1)

cmd/version.go

@@ -0,0 +1,47 @@
+// Copyright © 2018 NAME HERE <EMAIL ADDRESS>
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package cmd
+
+import (
+	"fmt"
+
+	"github.com/spf13/cobra"
+)
+
+// versionCmd represents the version command
+var versionCmd = &cobra.Command{
+	Use:   "version",
+	Short: "Shows version information",
+	Run: func(cmd *cobra.Command, args []string) {
+		fmt.Println("Demeter", info.Version)
+		fmt.Println("Build date:", info.Date)
+		fmt.Println("Commit hash:", info.Commit)
+		fmt.Println("Built by:", info.BuiltBy)
+	},
+}
+
+func init() {
+	rootCmd.AddCommand(versionCmd)
+
+	// Here you will define your flags and configuration settings.
+
+	// Cobra supports Persistent Flags which will work for this command
+	// and all subcommands, e.g.:
+	// resultsCmd.PersistentFlags().String("foo", "", "A help for foo")
+
+	// Cobra supports local flags which will only run when this command
+	// is called directly, e.g.:
+	// resultsCmd.Flags().BoolP("toggle", "t", false, "Help message for toggle")
+}

main.go

@@ -22,6 +22,16 @@ package main
 
 import "github.com/gnur/demeter/cmd"
 
+var version string
+var commit string
+var date string
+var builtBy string
+
 func main() {
-	cmd.Execute()
+	cmd.Execute(cmd.Info{
+		Version: version,
+		Commit:  commit,
+		Date:    date,
+		BuiltBy: builtBy,
+	})
 }