feat: Propagate exception from saml library to our logs

And make sure that we also log errors when processing SLO requests.

Signed-off-by: Carl Schwan <carlschwan@kde.org>

Author: CarlSchwan

lib/Controller/SAMLController.php

@@ -360,14 +360,7 @@ public function assertionConsumerService(): Http\RedirectResponse {
 
 		$this->logger->debug('Attributes send by the IDP: ' . json_encode($auth->getAttributes(), JSON_THROW_ON_ERROR));
 
-		$errors = $auth->getErrors();
-
-		if (!empty($errors)) {
-			foreach ($errors as $error) {
-				$this->logger->error($error, ['app' => $this->appName]);
-			}
-			$this->logger->error($auth->getLastErrorReason() ?? 'No last error reason found', ['app' => $this->appName]);
-		}
+		$this->handleAuthErrors($auth);
 
 		if (!$auth->isAuthenticated()) {
 			$this->logger->info('Auth failed', ['app' => $this->appName]);
@@ -530,6 +523,8 @@ private function tryProcessSLOResponse(?int $idp): array {
 				));
 				if ($auth->getLastErrorReason() === null) {
 					return [$targetUrl, $auth];
+				} else {
+					$this->handleAuthErrors($auth);
 				}
 			} catch (Error) {
 				continue;
@@ -660,4 +655,27 @@ public function base(): Http\TemplateResponse {
 		$message = $this->l->t('This page should not be visited directly.');
 		return new Http\TemplateResponse($this->appName, 'error', ['message' => $message], 'guest');
 	}
+
+	private function handleAuthErrors(Auth $auth): void {
+		$errors = $auth->getErrors();
+		$lastReason = $auth->getLastErrorReason();
+
+		if ($errors !== []) {
+			if ($lastReason === null) {
+				$this->logger->error('Got SAML error with no error message: ' . $errors[0] . '. This should not happen!');
+				return;
+			}
+
+			// Only the last error has a corresponding exception and reason
+			$this->logger->error('Got SAML error: ' . $lastReason . '(code: ' . $errors[count($errors) - 1] . ').', [
+				'exception' => $auth->getLastErrorException(),
+			]);
+
+			if (count($errors) > 1) {
+				for ($i = 1; $i < count($errors); $i++) {
+					$this->logger->error('Got additional SAML error code: ' . $errors[0]);
+				}
+			}
+		}
+	}
 }