can receive string message

luarocks/LuaWebSocket.h

@@ -1,3 +1,9 @@
+/*
+ *  LuaWebSocket.h
+ *  Author: Benjamin Sergeant
+ *  Copyright (c) 2020 Machine Zone, Inc. All rights reserved.
+ */
+
 #pragma once
 
 #include <iostream>
@@ -13,54 +19,116 @@ extern "C"
 #include <ixwebsocket/IXWebSocket.h>
 #include <chrono>
 #include <thread>
+#include <queue>
+#include <mutex>
 
-using namespace ix;
+namespace ix
-
-WebSocket* WebSocket_new(lua_State* L)
 {
-    WebSocket* webSocket = new WebSocket();
+    class LuaWebSocket
-    webSocket->setOnMessageCallback([](const WebSocketMessagePtr& msg) {
+    {
+        public:
+            LuaWebSocket()
+            {
+                _webSocket.setOnMessageCallback([this](const WebSocketMessagePtr& msg) {
                     if (msg->type == ix::WebSocketMessageType::Message)
                     {
-            std::cout << msg->str << std::endl;
+                        std::lock_guard<std::mutex> lock(_queueMutex);
+                        _queue.push(msg->str);
                     }
                 });
+            }
+
+            void setUrl(const std::string& url) { _webSocket.setUrl(url); }
+            const std::string& getUrl() { return _webSocket.getUrl(); }
+            void start() { _webSocket.start(); }
+            void send(const std::string& msg) { _webSocket.send(msg); }
+
+            const std::string& getMessage()
+            {
+                std::lock_guard<std::mutex> lock(_queueMutex);
+                return _queue.front();
+            }
+
+            bool hasMessage()
+            {
+                std::lock_guard<std::mutex> lock(_queueMutex);
+                return !_queue.empty();
+            }
+
+            void popMessage()
+            {
+                std::lock_guard<std::mutex> lock(_queueMutex);
+                _queue.pop();
+            }
+
+        private:
+            WebSocket _webSocket;
+
+            std::queue<std::string> _queue;
+            std::mutex _queueMutex;
+    };
+
+    LuaWebSocket* WebSocket_new(lua_State* L)
+    {
+        LuaWebSocket* webSocket = new LuaWebSocket();
         return webSocket;
     }
 
     int WebSocket_getUrl(lua_State* L)
     {
-    WebSocket* webSocket = luaW_check<WebSocket>(L, 1);
+        LuaWebSocket* luaWebSocket = luaW_check<LuaWebSocket>(L, 1);
-    lua_pushstring(L, webSocket->getUrl().c_str());
+        lua_pushstring(L, luaWebSocket->getUrl().c_str());
         return 1;
     }
 
     int WebSocket_setUrl(lua_State* L)
     {
-    WebSocket* webSocket = luaW_check<WebSocket>(L, 1);
+        LuaWebSocket* luaWebSocket = luaW_check<LuaWebSocket>(L, 1);
         const char* url = luaL_checkstring(L, 2);
-    webSocket->setUrl(url);
+        luaWebSocket->setUrl(url);
         return 0;
     }
 
     int WebSocket_start(lua_State* L)
     {
-    WebSocket* webSocket = luaW_check<WebSocket>(L, 1);
+        LuaWebSocket* luaWebSocket = luaW_check<LuaWebSocket>(L, 1);
-    webSocket->start();
+        luaWebSocket->start();
         return 0;
     }
 
     int WebSocket_send(lua_State* L)
     {
-    WebSocket* webSocket = luaW_check<WebSocket>(L, 1);
+        LuaWebSocket* luaWebSocket = luaW_check<LuaWebSocket>(L, 1);
         const char* msg = luaL_checkstring(L, 2);
-    webSocket->send(msg);
+        luaWebSocket->send(msg);
         return 0;
     }
 
+    int WebSocket_getMessage(lua_State* L)
+    {
+        LuaWebSocket* luaWebSocket = luaW_check<LuaWebSocket>(L, 1);
+        lua_pushstring(L, luaWebSocket->getMessage().c_str());
+        return 1;
+    }
+
+    int WebSocket_hasMessage(lua_State* L)
+    {
+        LuaWebSocket* luaWebSocket = luaW_check<LuaWebSocket>(L, 1);
+        lua_pushboolean(L, luaWebSocket->hasMessage());
+        return 1;
+    }
+
+    int WebSocket_popMessage(lua_State* L)
+    {
+        LuaWebSocket* luaWebSocket = luaW_check<LuaWebSocket>(L, 1);
+        luaWebSocket->popMessage();
+        return 1;
+    }
+
+    // This should be a static method
     int WebSocket_sleep(lua_State* L)
     {
-    WebSocket* webSocket = luaW_check<WebSocket>(L, 1);
+        LuaWebSocket* luaWebSocket = luaW_check<LuaWebSocket>(L, 1);
         int duration = luaL_checkinteger(L, 2);
         std::this_thread::sleep_for(std::chrono::milliseconds(duration));
         return 0;
@@ -75,13 +143,16 @@ static luaL_Reg WebSocket_metatable[] = {
         { "setUrl", WebSocket_setUrl },
         { "start", WebSocket_start },
         { "send", WebSocket_send },
+        { "getMessage", WebSocket_getMessage },
+        { "hasMessage", WebSocket_hasMessage },
+        { "popMessage", WebSocket_popMessage },
         { "sleep", WebSocket_sleep },
         { NULL, NULL }
     };
 
     int luaopen_WebSocket(lua_State* L)
     {
-    luaW_register<WebSocket>(L,
+        luaW_register<LuaWebSocket>(L,
             "WebSocket",
             WebSocket_table,
             WebSocket_metatable,
@@ -89,3 +160,4 @@ int luaopen_WebSocket(lua_State* L)
             );
         return 1;
     }
+}

luarocks/ia.lua

@@ -1,13 +1,28 @@
-webSocket = WebSocket.new()
+--
+-- make luarocks && (cd luarocks ; ../build/luarocks/luarocks)
+--
+local webSocket = WebSocket.new()
 
 webSocket:setUrl("ws://localhost:8008")
 print("Url: " .. webSocket:getUrl())
 
+-- Start the background thread
 webSocket:start()
 
+local i = 0
+
 while true
 do
-    print("Waiting ...")
+    print("Sending message...")
-    webSocket:send("coucou");
+    webSocket:send("msg_" .. tostring(i));
+    i = i + 1
+
+    print("Waiting 1s...")
     webSocket:sleep(1000)
+
+    if webSocket:hasMessage() then
+        local msg = webSocket:getMessage()
+        print("Received: " .. msg)
+        webSocket:popMessage()
+    end
 end

luarocks/main.cpp

@@ -1,3 +1,9 @@
+/*
+ *  main.cpp
+ *  Author: Benjamin Sergeant
+ *  Copyright (c) 2020 Machine Zone, Inc. All rights reserved.
+ */
+
 #include <iostream>
 
 extern "C"
@@ -20,29 +26,39 @@ int main()
     lua_register(L, "info", lua_info);
 
     // Objets
-    luaopen_WebSocket(L);
+    ix::luaopen_WebSocket(L);
 
-#if 0
+    //
-    luaL_dofile(L, "ia.lua");
+    // Simple version does little error handling
-#else
+    // luaL_dofile(L, "ia.lua");
-    int loadStatus = luaL_loadfile(L, "ia.lua");
+    //
+    std::string luaFile("ia.lua");
+    int loadStatus = luaL_loadfile(L, luaFile.c_str());
     if (loadStatus)
     {
-        std::cerr << "Error loading gof_server.lua" << std::endl;
+        std::cerr << "Error loading " << luaFile << std::endl;
         std::cerr << lua_tostring(L, -1) << std::endl;
         return 1;
     }
     else
     {
-        std::cout << "loaded ia.lua" << std::endl;
+        std::cout << "loaded " << luaFile << std::endl;
     }
 
-    try {
+    //
+    // Capture lua errors
+    //
+    try
+    {
         lua_call(L, 0, 0);
-    }
-    catch (const std::runtime_error& ex) {
-        std::cerr << ex.what() << std::endl;
-    }
-#endif
         lua_close(L);
     }
+    catch (const std::runtime_error& ex)
+    {
+        lua_close(L);
+        std::cerr << ex.what() << std::endl;
+        return 1;
+    }
+
+    return 0;
+}