client io architecture

pkg/util/fs.go

@@ -1,6 +1,7 @@
 package util
 
 import (
+	"fmt"
 	"os"
 	"testing"
 )
@@ -17,3 +18,25 @@ func CreateWorkDir(t *testing.T) (string, func()) {
 		}
 	}
 }
+
+func DirExists(path string) (bool, error) {
+	return PathExists(path, true)
+}
+
+func FileExists(path string) (bool, error) {
+	return PathExists(path, false)
+}
+
+func PathExists(path string, isDir bool) (bool, error) {
+	if fi, err := os.Stat(path); err != nil {
+		if os.IsNotExist(err) {
+			return false, nil
+		}
+		return false, err
+	} else {
+		if isDir != fi.IsDir() {
+			return false, fmt.Errorf("wrong type: "+path+" mode=%s isDir=%t", fi.Mode(), isDir)
+		}
+		return true, nil
+	}
+}