fix: logout when OpenID service is unavailable

packages/uni_app/lib/session/flows/federated/client.dart

@@ -0,0 +1,17 @@
+import 'package:http/http.dart' as http;
+import 'package:uni/http/client/timeout.dart';
+
+class FederatedDefaultClient extends http.BaseClient {
+  FederatedDefaultClient()
+      : inner = TimeoutClient(
+          http.Client(),
+          timeout: const Duration(seconds: 5),
+        );
+
+  final http.Client inner;
+
+  @override
+  Future<http.StreamedResponse> send(http.BaseRequest request) {
+    return inner.send(request);
+  }
+}

packages/uni_app/lib/session/flows/federated/initiator.dart

@@ -1,6 +1,11 @@
+import 'dart:async';
+
 import 'package:http/http.dart' as http;
 import 'package:openid_client/openid_client.dart';
+import 'package:sentry_flutter/sentry_flutter.dart';
+import 'package:uni/session/exception.dart';
 import 'package:uni/session/flows/base/initiator.dart';
+import 'package:uni/session/flows/federated/client.dart';
 import 'package:uni/session/flows/federated/request.dart';
 
 class FederatedSessionInitiator extends SessionInitiator {
@@ -14,11 +19,30 @@ class FederatedSessionInitiator extends SessionInitiator {
   final String clientId;
   final Future<Uri> Function(Flow flow) performAuthentication;
 
+  Future<T> _handleOpenIdExceptions<T>(
+    Future<T> future, {
+    required AuthenticationException onError,
+  }) {
+    T reportExceptionAndFail<E extends Object>(E error, StackTrace st) {
+      unawaited(Sentry.captureException(error, stackTrace: st));
+      throw onError;
+    }
+
+    return future
+        .onError<HttpRequestException>(reportExceptionAndFail)
+        .onError<OpenIdException>(reportExceptionAndFail);
+  }
+
   @override
   Future<FederatedSessionRequest> initiate([http.Client? httpClient]) async {
-    final issuer = await Issuer.discover(realm);
-    final client = Client(issuer, clientId, httpClient: httpClient);
+    httpClient ??= FederatedDefaultClient();
 
+    final issuer = await _handleOpenIdExceptions(
+      Issuer.discover(realm, httpClient: httpClient),
+      onError: const AuthenticationException('Failed to discover OIDC issuer'),
+    );
+
+    final client = Client(issuer, clientId, httpClient: httpClient);
     final flow = Flow.authorizationCodeWithPKCE(
       client,
       scopes: [
@@ -32,7 +56,10 @@ class FederatedSessionInitiator extends SessionInitiator {
     );
 
     final uri = await performAuthentication(flow);
-    final credential = await flow.callback(uri.queryParameters);
+    final credential = await _handleOpenIdExceptions(
+      flow.callback(uri.queryParameters),
+      onError: const AuthenticationException('Failed to execute flow callback'),
+    );
 
     return FederatedSessionRequest(credential: credential);
   }

packages/uni_app/lib/session/flows/federated/request.dart

@@ -1,10 +1,15 @@
+import 'dart:async';
+
 import 'package:http/http.dart' as http;
 import 'package:openid_client/openid_client.dart';
+import 'package:sentry_flutter/sentry_flutter.dart';
 import 'package:uni/controller/fetchers/faculties_fetcher.dart';
 import 'package:uni/session/exception.dart';
 import 'package:uni/session/flows/base/request.dart';
+import 'package:uni/session/flows/federated/client.dart';
 import 'package:uni/session/flows/federated/session.dart';
 import 'package:uni/sigarra/endpoints/oidc/oidc.dart';
+import 'package:uni/sigarra/endpoints/oidc/token/response.dart';
 import 'package:uni/sigarra/options.dart';
 
 class FederatedSessionUserInfo {
@@ -38,18 +43,29 @@ class FederatedSessionRequest extends SessionRequest {
 
   final Credential credential;
 
+  TokenFailedResponse _reportExceptionAndFail<E extends Object>(
+    E error,
+    StackTrace st,
+  ) {
+    unawaited(Sentry.captureException(error, stackTrace: st));
+    return const TokenFailedResponse();
+  }
+
   @override
   Future<FederatedSession> perform([http.Client? httpClient]) async {
-    final client = httpClient ?? http.Client();
+    httpClient ??= FederatedDefaultClient();
 
-    final authorizedClient = credential.createHttpClient(client);
+    final authorizedClient = credential.createHttpClient(httpClient);
 
     final oidc = SigarraOidc();
-    final response = await oidc.token.call(
-      options: BaseRequestOptions(
-        client: authorizedClient,
-      ),
-    );
+    final response = await oidc.token
+        .call(
+          options: BaseRequestOptions(
+            client: authorizedClient,
+          ),
+        )
+        .onError<OpenIdException>(_reportExceptionAndFail)
+        .onError<HttpRequestException>(_reportExceptionAndFail);
 
     if (!response.success) {
       throw const AuthenticationException('Failed to get OIDC token');
@@ -65,7 +81,7 @@ class FederatedSessionRequest extends SessionRequest {
       credential: credential,
     );
 
-    final faculties = await getStudentFaculties(tempSession, client);
+    final faculties = await getStudentFaculties(tempSession, httpClient);
 
     return FederatedSession(
       username: userInfo.username,