create new config if doesn't exists

Author: SaintWish

cmd/app/app.go

@@ -92,10 +92,22 @@ func (a *App) CalcHashes() error {
 	return nil
 }*/
 
-func (a *App) LoadConfig(path string) (err error) {
-	a.Config, err = config.Load(path)
+func (a *App) LoadConfig(path string) (error) {
+	cfg, err := config.Load(path)
+	if err != nil && os.IsNotExist(err) {
+		fmt.Println("Config file is missing, creating new one!")
 
-	return
+		if err := utils.CopyFile("./runtime/config.example.yaml", path); err != nil {
+			return fmt.Errorf("Unable to create new config %w", err)
+		}
+
+		return a.LoadConfig(path)
+	} else if err != nil {
+		return fmt.Errorf("Unable to load config file %w", err)
+	}
+
+	a.Config = cfg
+	return nil
 }
 
 func (a *App) InitializeLogger() (err error) {

pkg/utils/file.go

@@ -0,0 +1,63 @@
+package utils
+
+import (
+	"fmt"
+	"io"
+	"os"
+)
+
+// Credit to https://stackoverflow.com/a/21067803
+// CopyFile copies a file from src to dst. If src and dst files exist, and are
+// the same, then return success. Otherise, attempt to create a hard link
+// between the two files. If that fail, copy the file contents from src to dst.
+func CopyFile(src, dst string) (err error) {
+	sfi, err := os.Stat(src)
+	if err != nil {
+		return
+	}
+	if !sfi.Mode().IsRegular() {
+		// cannot copy non-regular files (e.g., directories,
+		// symlinks, devices, etc.)
+		return fmt.Errorf("CopyFile: non-regular source file %s (%q)", sfi.Name(), sfi.Mode().String())
+	}
+	dfi, err := os.Stat(dst)
+	if err != nil {
+		if !os.IsNotExist(err) {
+			return
+		}
+	} else {
+		if !(dfi.Mode().IsRegular()) {
+			return fmt.Errorf("CopyFile: non-regular destination file %s (%q)", dfi.Name(), dfi.Mode().String())
+		}
+	}
+
+	err = copyFileContents(src, dst)
+	return
+}
+
+// copyFileContents copies the contents of the file named src to the file named
+// by dst. The file will be created if it does not already exist. If the
+// destination file exists, all it's contents will be replaced by the contents
+// of the source file.
+func copyFileContents(src, dst string) (err error) {
+	in, err := os.Open(src)
+	if err != nil {
+		return
+	}
+	defer in.Close()
+	out, err := os.Create(dst)
+	if err != nil {
+		return
+	}
+	defer func() {
+		cerr := out.Close()
+		if err == nil {
+			err = cerr
+		}
+	}()
+	if _, err = io.Copy(out, in); err != nil {
+		return
+	}
+	err = out.Sync()
+	return
+}