Add a service to announce multiplayer rooms to web service; Add the abiltiy to receive a list of all announced rooms from web service

src/web_service/announce_room_json.h

@@ -0,0 +1,42 @@
+// Copyright 2017 Citra Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include <functional>
+#include <future>
+#include <string>
+#include "common/announce_multiplayer_room.h"
+
+namespace WebService {
+
+/**
+ * Implementation of AnnounceMultiplayerRoom::Backend that (de)serializes room information into/from
+ * JSON, and submits/gets it to/from the Citra web service
+ */
+class RoomJson : public AnnounceMultiplayerRoom::Backend {
+public:
+    RoomJson(const std::string& endpoint_url, const std::string& username, const std::string& token)
+        : endpoint_url(endpoint_url), username(username), token(token) {}
+    ~RoomJson() = default;
+    void SetRoomInformation(const std::string& guid, const std::string& name, const u16 port,
+                            const u32 max_player, const u32 net_version, const bool has_password,
+                            const std::string& preferred_game,
+                            const u64 preferred_game_id) override;
+    void AddPlayer(const std::string& nickname,
+                   const AnnounceMultiplayerRoom::MacAddress& mac_address, const u64 game_id,
+                   const std::string& game_name) override;
+    std::future<Common::WebResult> Announce() override;
+    void ClearPlayers() override;
+    std::future<AnnounceMultiplayerRoom::RoomList> GetRoomList(std::function<void()> func) override;
+    void Delete() override;
+
+private:
+    AnnounceMultiplayerRoom::Room room;
+    std::string endpoint_url;
+    std::string username;
+    std::string token;
+};
+
+} // namespace WebService