Fixed null user being returned if id not in database

db/user_functions.go

@@ -56,11 +56,12 @@ func fetchUserData(
 	return rows, nil
 }
 
-// Scan the next row into the provided user pointer. Calls rows.Next() and
-// assumes only row in the result. Providing a rows object with more than 1
-// row may result in undefined behaviour.
+// Calls rows.Next() and scans the row into the provided user pointer.
+// Will error if no row available
 func scanUserRow(user *User, rows *sql.Rows) error {
-	for rows.Next() {
+	if !rows.Next() {
+		return errors.New("User not found")
+	}
 	err := rows.Scan(
 		&user.ID,
 		&user.Username,
@@ -71,7 +72,6 @@ func scanUserRow(user *User, rows *sql.Rows) error {
 	if err != nil {
 		return errors.Wrap(err, "rows.Scan")
 	}
-	}
 	return nil
 }