From 67fd9cd00e606b76e12665c7f54f9972469edfaf Mon Sep 17 00:00:00 2001
From: Christian Pauly <christian-pauly@posteo.de>
Date: Tue, 8 Nov 2022 09:42:21 +0100
Subject: [PATCH] refactor: Improve error handling for no olm session found
 exception

Finding no olm session can
happen quiet often when there
are dead devices in a room.
We do not need to print the
whole stacktrace then.
---
 lib/encryption/olm_manager.dart | 25 +++++++++++++++++++++++--
 1 file changed, 23 insertions(+), 2 deletions(-)

diff --git a/lib/encryption/olm_manager.dart b/lib/encryption/olm_manager.dart
index 4fb7a0bd..0470bdef 100644
--- a/lib/encryption/olm_manager.dart
+++ b/lib/encryption/olm_manager.dart
@@ -566,6 +566,10 @@ class OlmManager {
           if (fingerprintKey == null ||
               identityKey == null ||
               !deviceKey.checkJsonSignature(fingerprintKey, userId, deviceId)) {
+            Logs().w(
+              'Skipping invalid device key from $userId:$deviceId',
+              deviceKey,
+            );
             continue;
           }
           Logs().v('[OlmManager] Starting session with $userId:$deviceId');
@@ -591,13 +595,17 @@ class OlmManager {
     }
   }
 
+  /// Encryptes a ToDeviceMessage for the given device with an existing
+  /// olm session.
+  /// Throws `NoOlmSessionFoundException` if there is no olm session with this
+  /// device and none could be created.
   Future<Map<String, dynamic>> encryptToDeviceMessagePayload(
       DeviceKeys device, String type, Map<String, dynamic> payload,
       {bool getFromDb = true}) async {
     final sess =
         await getOlmSessions(device.curve25519Key!, getFromDb: getFromDb);
     if (sess.isEmpty) {
-      throw ('No olm session found for ${device.userId}:${device.deviceId}');
+      throw NoOlmSessionFoundException(device);
     }
     final fullPayload = {
       'type': type,
@@ -653,8 +661,11 @@ class OlmManager {
         userData[device.deviceId!] = await encryptToDeviceMessagePayload(
             device, type, payload,
             getFromDb: false);
+      } on NoOlmSessionFoundException catch (e) {
+        Logs().d('[LibOlm] Error encrypting to-device event', e);
+        continue;
       } catch (e, s) {
-        Logs().w('[LibOlm] Error encrypting to-device event', e, s);
+        Logs().wtf('[LibOlm] Error encrypting to-device event', e, s);
         continue;
       }
     }
@@ -706,3 +717,13 @@ class OlmManager {
     _olmAccount = null;
   }
 }
+
+class NoOlmSessionFoundException implements Exception {
+  final DeviceKeys device;
+
+  NoOlmSessionFoundException(this.device);
+
+  @override
+  String toString() =>
+      'No olm session found for ${device.userId}:${device.deviceId}';
+}