[feature] Add `created_at` and `error_description` to `/oauth/token` endpoint (#645)

* start fiddling about with oauth server

* start returning more helpful errors from oauth

* test helpful(ish) token errors

* add missing license header

1 files changed, 26 insertions, 0 deletions

diff --git a/internal/oauth/errors.go b/internal/oauth/errors.go
new file mode 100644
index 000000000..25278bdc9
--- /dev/null
+++ b/internal/oauth/errors.go
@@ -0,0 +1,26 @@
+/*
+   GoToSocial
+   Copyright (C) 2021-2022 GoToSocial Authors admin@gotosocial.org
+
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU Affero General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU Affero General Public License for more details.
+
+   You should have received a copy of the GNU Affero General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+package oauth
+
+import "github.com/superseriousbusiness/oauth2/v4/errors"
+
+// InvalidRequest returns an oauth spec compliant 'invalid_request' error.
+func InvalidRequest() error {
+	return errors.New("invalid_request")
+}