Implemented self-update

Author: permito

hp/cmd/update.go

@@ -0,0 +1,34 @@
+package cmd
+
+import (
+	"HeaderPuller/hp"
+	"errors"
+	"github.com/urfave/cli/v2"
+	"os"
+	"os/exec"
+	"strconv"
+	"time"
+)
+
+var UpdateCmd = &cli.Command{
+	Name:    "update",
+	Aliases: []string{"u"},
+	Usage:   "Update to the latest git commit",
+	Action: func(cCtx *cli.Context) error {
+		executablePath, err := exec.LookPath("hp")
+		if err != nil {
+			return errors.New("hp executable not found, update unable to finish")
+		}
+
+		tmp := strconv.Itoa(time.Now().Nanosecond())
+		if err := exec.Command("git", "clone", "https://github.com/Depermitto/HeaderPuller", tmp).Run(); err != nil {
+			return errors.New("cannot clone repo, update unable to finish")
+		}
+		defer os.RemoveAll(tmp)
+
+		if err := exec.Command("go", "build", "-C", tmp, "-o", executablePath).Run(); err != nil {
+			return errors.New("errors found in building the executable, update unable to finish")
+		}
+		return hp.NoErrUpdated
+	},
+}

hp/hp.go

@@ -9,6 +9,7 @@ const (
 	IncludeDir = "include"
 	PathSep    = string(os.PathSeparator)
 	Perm       = 0755
+	RepoLink   = "https://github.com/Depermitto/HeaderPuller"
 )
 
 var (
@@ -21,4 +22,5 @@ var (
 	NoErrWiped           = errors.New("wipe successful")
 	NoErrRemoved         = errors.New("removal successful")
 	NoErrSynced          = errors.New("sync successful")
+	NoErrUpdated         = errors.New("update successful")
 )

main.go

@@ -20,6 +20,7 @@ func main() {
 			cmd.SyncCmd,
 			cmd.RemoveCmd,
 			cmd.WipeCmd,
+			cmd.UpdateCmd,
 			cmd.VersionCmd,
 			cmd.UninstallCmd,
 		}}