core, web_service: Check for error when registering rooms

The `Register()` function can now handle error results and the error will be passed immediately to the Qt frontend, instead of being ignored silently and failing later with a "Room is not registered".

src/citra_qt/multiplayer/host_room.cpp

@@ -7,6 +7,7 @@
 #include <QImage>
 #include <QList>
 #include <QLocale>
+#include <QMessageBox>
 #include <QMetaType>
 #include <QTime>
 #include <QtConcurrent/QtConcurrentRun>
@@ -148,7 +149,22 @@ void HostRoomWindow::Host() {
         if (is_public) {
             if (auto session = announce_multiplayer_session.lock()) {
                 // Register the room first to ensure verify_UID is present when we connect
-                session->Register();
+                Common::WebResult result = session->Register();
+                if (result.result_code != Common::WebResult::Code::Success) {
+                    QMessageBox::warning(
+                        this, tr("Error"),
+                        tr("Failed to announce the room to the public lobby. In order to host a "
+                           "room publicly, you must have a valid Citra account configured in "
+                           "Emulation -> Configure -> Web. If you do not want to publish a room in "
+                           "the public lobby, then select Unlisted instead.\nDebug Message: ") +
+                            QString::fromStdString(result.result_string),
+                        QMessageBox::Ok);
+                    ui->host->setEnabled(true);
+                    if (auto room = Network::GetRoom().lock()) {
+                        room->Destroy();
+                    }
+                    return;
+                }
                 session->Start();
             } else {
                 LOG_ERROR(Network, "Starting announce session failed");

src/citra_qt/multiplayer/state.cpp

@@ -174,14 +174,11 @@ void MultiplayerState::OnNetworkError(const Network::RoomMember::Error& error) {
 
 void MultiplayerState::OnAnnounceFailed(const Common::WebResult& result) {
     announce_multiplayer_session->Stop();
-    QMessageBox::warning(
-        this, tr("Error"),
-        tr("Failed to announce the room to the public lobby. In order to host a room publicly, you "
-           "must have a valid Citra account configured in Emulation -> Configure -> Web. If you do "
-           "not want to publish a room in the public lobby, then select Unlisted instead.\n"
-           "Debug Message: ") +
-            QString::fromStdString(result.result_string),
-        QMessageBox::Ok);
+    QMessageBox::warning(this, tr("Error"),
+                         tr("Failed to update the room information. Please check your Internet "
+                            "connection and try hosting the room again.\nDebug Message: ") +
+                             QString::fromStdString(result.result_string),
+                         QMessageBox::Ok);
 }
 
 void MultiplayerState::UpdateThemedIcons() {

src/common/announce_multiplayer_room.h

@@ -83,9 +83,10 @@ public:
 
     /**
      * Registers the data in the announce service
-     * @result A global Guid of the room which may be used for verification
+     * @result The result of the register attempt. When the result code is Success, A global Guid of
+     * the room which may be used for verification will be in the result's returned_data.
      */
-    virtual std::string Register() = 0;
+    virtual Common::WebResult Register() = 0;
 
     /**
      * Empties the stored players
@@ -121,8 +122,8 @@ public:
     Common::WebResult Update() override {
         return Common::WebResult{Common::WebResult::Code::NoWebservice, "WebService is missing"};
     }
-    std::string Register() override {
-        return "";
+    Common::WebResult Register() override {
+        return Common::WebResult{Common::WebResult::Code::NoWebservice, "WebService is missing"};
     }
     void ClearPlayers() override {}
     RoomList GetRoomList() override {

src/core/announce_multiplayer_session.cpp

@@ -29,19 +29,23 @@ AnnounceMultiplayerSession::AnnounceMultiplayerSession() {
 #endif
 }
 
-void AnnounceMultiplayerSession::Register() {
+Common::WebResult AnnounceMultiplayerSession::Register() {
     std::shared_ptr<Network::Room> room = Network::GetRoom().lock();
     if (!room) {
-        return;
+        return Common::WebResult{Common::WebResult::Code::LibError, "Network is not initialized"};
     }
     if (room->GetState() != Network::Room::State::Open) {
-        return;
+        return Common::WebResult{Common::WebResult::Code::LibError, "Room is not open"};
     }
     UpdateBackendData(room);
-    std::string result = backend->Register();
+    Common::WebResult result = backend->Register();
+    if (result.result_code != Common::WebResult::Code::Success) {
+        return result;
+    }
     LOG_INFO(WebService, "Room has been registered");
-    room->SetVerifyUID(result);
+    room->SetVerifyUID(result.returned_data);
     registered = true;
+    return Common::WebResult{Common::WebResult::Code::Success};
 }
 
 void AnnounceMultiplayerSession::Start() {
@@ -95,9 +99,22 @@ void AnnounceMultiplayerSession::UpdateBackendData(std::shared_ptr<Network::Room
 }
 
 void AnnounceMultiplayerSession::AnnounceMultiplayerLoop() {
+    // Invokes all current bound error callbacks.
+    const auto ErrorCallback = [this](Common::WebResult result) {
+        std::lock_guard<std::mutex> lock(callback_mutex);
+        for (auto callback : error_callbacks) {
+            (*callback)(result);
+        }
+    };
+
     if (!registered) {
-        Register();
+        Common::WebResult result = Register();
+        if (result.result_code != Common::WebResult::Code::Success) {
+            ErrorCallback(result);
+            return;
+        }
     }
+
     auto update_time = std::chrono::steady_clock::now();
     std::future<Common::WebResult> future;
     while (!shutdown_event.WaitUntil(update_time)) {
@@ -112,15 +129,15 @@ void AnnounceMultiplayerSession::AnnounceMultiplayerLoop() {
         UpdateBackendData(room);
         Common::WebResult result = backend->Update();
         if (result.result_code != Common::WebResult::Code::Success) {
-            std::lock_guard lock(callback_mutex);
-            for (auto callback : error_callbacks) {
-                (*callback)(result);
-            }
+            ErrorCallback(result);
         }
         if (result.result_string == "404") {
             registered = false;
             // Needs to register the room again
-            Register();
+            Common::WebResult result = Register();
+            if (result.result_code != Common::WebResult::Code::Success) {
+                ErrorCallback(result);
+            }
         }
     }
 }

src/core/announce_multiplayer_session.h

@@ -44,8 +44,11 @@ public:
      */
     void UnbindErrorCallback(CallbackHandle handle);
 
-    /// Registers a room to web services
-    void Register();
+    /**
+     * Registers a room to web services
+     * @return The result of the registration attempt.
+     */
+    Common::WebResult Register();
 
     /**
      * Starts the announce of a room to web services

src/web_service/announce_room_json.cpp

@@ -117,16 +117,16 @@ Common::WebResult RoomJson::Update() {
     return client.PostJson(fmt::format("/lobby/{}", room_id), json.dump(), false);
 }
 
-std::string RoomJson::Register() {
+Common::WebResult RoomJson::Register() {
     nlohmann::json json = room;
-    auto reply = client.PostJson("/lobby", json.dump(), false).returned_data;
-    if (reply.empty()) {
-        return "";
+    auto result = client.PostJson("/lobby", json.dump(), false);
+    if (result.result_code != Common::WebResult::Code::Success) {
+        return result;
     }
-    auto reply_json = nlohmann::json::parse(reply);
+    auto reply_json = nlohmann::json::parse(result.returned_data);
     room = reply_json.get<AnnounceMultiplayerRoom::Room>();
     room_id = reply_json.at("id").get<std::string>();
-    return room.verify_UID;
+    return Common::WebResult{Common::WebResult::Code::Success, "", room.verify_UID};
 }
 
 void RoomJson::ClearPlayers() {

src/web_service/announce_room_json.h

@@ -29,7 +29,7 @@ public:
                    const AnnounceMultiplayerRoom::MacAddress& mac_address, const u64 game_id,
                    const std::string& game_name) override;
     Common::WebResult Update() override;
-    std::string Register() override;
+    Common::WebResult Register() override;
     void ClearPlayers() override;
     AnnounceMultiplayerRoom::RoomList GetRoomList() override;
     void Delete() override;