Matrix: fetch user if the user is not available for some reason (synapse bug?)

2 files changed, 52 insertions, 24 deletions

diff --git a/plugins/Matrix.hpp b/plugins/Matrix.hpp
index d9e6a97..20ad7da 100644
--- a/plugins/Matrix.hpp
+++ b/plugins/Matrix.hpp
@@ -451,6 +451,7 @@ namespace QuickMedia {
         PluginResult parse_sync_room_data(const rapidjson::Value &rooms_json);
         PluginResult get_previous_room_messages(RoomData *room_data);
         void events_add_user_info(const rapidjson::Value &events_json, RoomData *room_data);
+        std::shared_ptr<UserInfo> parse_user_info(const rapidjson::Value &json, const std::string &user_id, RoomData *room_data);
         void events_add_user_read_markers(const rapidjson::Value &events_json, RoomData *room_data);
         void events_set_user_read_marker(const rapidjson::Value &events_json, RoomData *room_data, std::shared_ptr<UserInfo> &me);
         void events_add_messages(const rapidjson::Value &events_json, RoomData *room_data, MessageDirection message_dir, bool has_unread_notifications);
@@ -469,6 +470,7 @@ namespace QuickMedia {
         void set_next_batch(std::string new_next_batch);
         std::string get_next_batch();
         void clear_sync_cache_for_new_sync();
+        std::shared_ptr<UserInfo> get_user_by_id(RoomData *room, const std::string &user_id);
         DownloadResult download_json(rapidjson::Document &result, const std::string &url, std::vector<CommandArg> additional_args, bool use_browser_useragent = false, std::string *err_msg = nullptr) const;
     private:
         std::vector<std::unique_ptr<RoomData>> rooms;
diff --git a/src/plugins/Matrix.cpp b/src/plugins/Matrix.cpp
index 2e96cd0..5a85e8e 100644
--- a/src/plugins/Matrix.cpp
+++ b/src/plugins/Matrix.cpp
@@ -1307,28 +1307,33 @@ namespace QuickMedia {
             if(!membership_json.IsString() || strcmp(membership_json.GetString(), "join") != 0)
                 continue;
 
-            std::string avatar_url_str;
-            const rapidjson::Value &avatar_url_json = GetMember(content_json, "avatar_url");
-            if(avatar_url_json.IsString())
-                avatar_url_str = avatar_url_json.GetString();
+            std::string sender_json_str = sender_json.GetString();
+            parse_user_info(content_json, sender_json_str, room_data);
+        }
+    }
 
-            const rapidjson::Value &display_name_json = GetMember(content_json, "displayname");
+    std::shared_ptr<UserInfo> Matrix::parse_user_info(const rapidjson::Value &json, const std::string &user_id, RoomData *room_data) {
+        assert(json.IsObject());
+        std::string avatar_url_str;
+        const rapidjson::Value &avatar_url_json = GetMember(json, "avatar_url");
+        if(avatar_url_json.IsString())
+            avatar_url_str = avatar_url_json.GetString();
 
-            std::string sender_json_str = sender_json.GetString();
+        const rapidjson::Value &display_name_json = GetMember(json, "displayname");
 
-            auto user_info = std::make_shared<UserInfo>();
-            user_info->user_id = sender_json_str;
-            user_info->avatar_url = std::move(avatar_url_str);
-            if(strncmp(user_info->avatar_url.c_str(), "mxc://", 6) == 0)
-                user_info->avatar_url.erase(user_info->avatar_url.begin(), user_info->avatar_url.begin() + 6);
-            if(!user_info->avatar_url.empty())
-                user_info->avatar_url = homeserver + "/_matrix/media/r0/thumbnail/" + user_info->avatar_url + "?width=32&height=32&method=crop"; // TODO: Remove the constant strings around to reduce memory usage (6.3mb)
-            user_info->display_name = display_name_json.IsString() ? display_name_json.GetString() : sender_json_str;
-            user_info->display_name_color = user_id_to_color(sender_json_str);
-            
-            // Overwrites user data
-            room_data->add_user(std::move(user_info));
-        }
+        auto user_info = std::make_shared<UserInfo>();
+        user_info->user_id = user_id;
+        user_info->avatar_url = std::move(avatar_url_str);
+        if(strncmp(user_info->avatar_url.c_str(), "mxc://", 6) == 0)
+            user_info->avatar_url.erase(user_info->avatar_url.begin(), user_info->avatar_url.begin() + 6);
+        if(!user_info->avatar_url.empty())
+            user_info->avatar_url = homeserver + "/_matrix/media/r0/thumbnail/" + user_info->avatar_url + "?width=32&height=32&method=crop"; // TODO: Remove the constant strings around to reduce memory usage (6.3mb)
+        user_info->display_name = display_name_json.IsString() ? display_name_json.GetString() : user_id;
+        user_info->display_name_color = user_id_to_color(user_id);
+        
+        // Overwrites user data
+        room_data->add_user(user_info);
+        return user_info;
     }
 
     void Matrix::events_add_user_read_markers(const rapidjson::Value &events_json, RoomData *room_data) {
@@ -1369,7 +1374,7 @@ namespace QuickMedia {
                     if(!user_id_json.IsString())
                         continue;
 
-                    auto user = room_data->get_user_by_id(user_id_json.GetString());
+                    auto user = get_user_by_id(room_data, user_id_json.GetString());
                     if(!user) {
                         fprintf(stderr, "Read receipt for unknown user: %s, ignoring...\n", user_id_json.GetString());
                         continue;
@@ -1575,7 +1580,7 @@ namespace QuickMedia {
         if(!content_json->IsObject())
             return nullptr;
 
-        auto user = room_data->get_user_by_id(sender_json_str);
+        auto user = get_user_by_id(room_data, sender_json_str);
         if(!user) {
             // Note: this is important because otherwise replying and such is broken
             fprintf(stderr, "Warning: skipping unknown user: %s\n", sender_json_str.c_str());
@@ -1809,7 +1814,7 @@ namespace QuickMedia {
 
             if(!has_room_avatar_url) {
                 if(users_excluding_me.empty()) {
-                    auto user = room_data->get_user_by_id(creator_json.GetString());
+                    auto user = get_user_by_id(room_data, creator_json.GetString());
                     if(user)
                         room_data->set_avatar_url(user->avatar_url);
                 } else {
@@ -1971,7 +1976,7 @@ namespace QuickMedia {
                     events_add_user_info(events_json, &invite_room);
                     events_set_room_name(events_json, &invite_room);
 
-                    auto invited_by = invite_room.get_user_by_id(sender_json.GetString());
+                    auto invited_by = get_user_by_id(&invite_room, sender_json.GetString());
                     if(!invited_by) {
                         fprintf(stderr, "Invited by unknown user. Bug in homeserver?\n");
                         break;
@@ -3015,7 +3020,7 @@ namespace QuickMedia {
     }
 
     std::shared_ptr<UserInfo> Matrix::get_me(RoomData *room) {
-        return room->get_user_by_id(user_id);
+        return get_user_by_id(room, user_id);
     }
 
     RoomData* Matrix::get_room_by_id(const std::string &id) {
@@ -3082,6 +3087,27 @@ namespace QuickMedia {
         delegate->clear_data();
     }
 
+    std::shared_ptr<UserInfo> Matrix::get_user_by_id(RoomData *room, const std::string &user_id) {
+        auto user = room->get_user_by_id(user_id);
+        if(user)
+            return user;
+
+        // TODO: Instead of guessing notification limit with 100, accumulate rooms unread_notifications count and use that as the limit
+        // (and take into account that notification response may have notifications after call to sync above).
+        char url[512];
+        snprintf(url, sizeof(url), "%s/_matrix/client/r0/profile/%s", homeserver.c_str(), user_id.c_str());
+
+        rapidjson::Document json_root;
+        DownloadResult download_result = download_json(json_root, url, {}, true);
+        if(download_result != DownloadResult::OK || !json_root.IsObject()) {
+            fprintf(stderr, "Fetching profile for user %s failed!\n", user_id.c_str());
+            return nullptr;
+        }
+
+        fprintf(stderr, "User was not available locally, fetched from server...\n");
+        return parse_user_info(json_root, user_id, room);
+    }
+
     DownloadResult Matrix::download_json(rapidjson::Document &result, const std::string &url, std::vector<CommandArg> additional_args, bool use_browser_useragent, std::string *err_msg) const {
         if(download_to_json(url, result, std::move(additional_args), use_tor, use_browser_useragent, err_msg == nullptr) != DownloadResult::OK) {
             // Cant get error since we parse directly to json. TODO: Make this work somehow?