add utils.UnwrapError() to provide meaningful error messages

utils/matrix.go

@@ -1,6 +1,7 @@
 package utils
 
 import (
+	"maunium.net/go/mautrix"
 	"maunium.net/go/mautrix/event"
 	"maunium.net/go/mautrix/id"
 )
@@ -24,3 +25,29 @@ func RelatesTo(noThreads bool, parentID id.EventID) *event.RelatesTo {
 		EventID: parentID,
 	}
 }
+
+// UnwrapError tries to unwrap a error into something meaningful, like mautrix.HTTPError or mautrix.RespError
+func UnwrapError(err error) error {
+	switch err.(type) {
+	case nil:
+		return nil
+	case mautrix.HTTPError:
+		return unwrapHTTPError(err)
+	default:
+		return err
+	}
+}
+
+func unwrapHTTPError(err error) error {
+	httperr, ok := err.(mautrix.HTTPError)
+	if !ok {
+		return err
+	}
+
+	uwerr := httperr.Unwrap()
+	if uwerr != nil {
+		return uwerr
+	}
+
+	return httperr
+}