Get() methods from all repositories now return a ErrNotFound when the id is nonexistent

domain/base.go

@@ -1,11 +1,17 @@
 package domain
 
+import "errors"
+
 type BaseRepository interface {
 	NewId(fields ...string) string
 	CountAll() (int64, error)
 	Exists(id string) (bool, error)
 }
 
+var (
+	ErrNotFound = errors.New("Data not found")
+)
+
 type QueryOptions struct {
 	SortBy string
 	Alpha  bool