Refine RPC library

Got multiple remote calls from one client working

Improved error messages

Got function name and arguments sent over as well as return values

cpp-console-game/main.cpp

@@ -51,6 +51,30 @@ void renderLoop()
   }
 }
 
+std::pair<bool, std::string> movePlayer(std::vector<std::string> args)
+{
+  int playerId = std::stoi(args[0]);
+  int x = std::stoi(args[1]);
+  int y = std::stoi(args[2]);
+
+  //gameState.movePlayer(playerId, {x, y});
+  std::cout << "Player " << playerId << " moved to (" << x << ", " << y << ")" << std::endl;
+
+  return {true, "Move Successful"};
+}
+
+std::pair<bool, std::string> echo(std::vector<std::string> args)
+{
+  for (auto arg : args)
+  {
+    std::cout << arg << " ";
+  }
+
+  std::cout << std::endl;
+
+  return {true, "Echo Successful"};
+}
+
 int main(int argc, char **argv)
 {
   if (argc < 4)
@@ -66,14 +90,20 @@ int main(int argc, char **argv)
   if (mode == "server")
   {
     eRPC::Server server(port);
+    server.bindMethod("movePlayer", movePlayer);
+    server.bindMethod("echo", echo);
     server.start();
   }
   else if (mode == "client")
   {
     eRPC::Client client(host, port);
-    client.openConnection();
-    client.call("Hello from client");
-    client.closeConnection();
+    
+    client.call("echo", {"Hello", "World"});
+    client.call("movePlayer", {"1", "5", "5"});
+    client.call("movePlayer", {"1", "6", "6"});
+    auto ret = client.call("echol", {"Goodbye", "World"});
+
+    std::cout << "Result: " << ret << std::endl;
   }
   else
   {

eRPC/Client.cpp

@@ -8,25 +8,22 @@
 #include <unistd.h>
 #include <iostream>
 
+int msgIdCounter = 0;
+
 namespace eRPC
 {
-  Client::Client(std::string host, int port) : sockfd(-1), serv_addr()
+  Client::Client(std::string host, int port) : sockfd(-1), serverAddress()
   {
-    if ((sockfd = socket(AF_INET, SOCK_STREAM, 0)) < 0)
-    {
-      throw std::runtime_error("Failed to create socket");
-    }
+    sockaddr_in serverAddress;
+    serverAddress.sin_family = AF_INET;
+    serverAddress.sin_port = htons(port);
 
-    sockaddr_in serv_addr;
-    serv_addr.sin_family = AF_INET;
-    serv_addr.sin_port = htons(port);
-
-    if (inet_pton(AF_INET, host.c_str(), &serv_addr.sin_addr) <= 0)
+    if (inet_pton(AF_INET, host.c_str(), &serverAddress.sin_addr) <= 0)
     {
       throw std::runtime_error("Invalid address");
     }
 
-    this->serv_addr = serv_addr;
+    this->serverAddress = serverAddress;
   }
 
   Client::~Client()
@@ -36,39 +33,43 @@ namespace eRPC
 
   void Client::openConnection()
   {
-    if (sockfd < 0)
+    if ((sockfd = socket(AF_INET, SOCK_STREAM, 0)) < 0)
     {
-      throw std::runtime_error("Socket not created");
+      throw std::runtime_error("Failed to create socket");
     }
 
-    if (connect(sockfd, (sockaddr *)&serv_addr, sizeof(serv_addr)) < 0)
+    if (connect(sockfd, (sockaddr *)&serverAddress, sizeof(serverAddress)) < 0)
     {
       throw std::runtime_error("Failed to connect to server");
     }
-
-    std::cout << "Connected to server" << std::endl;
   }
 
   void Client::closeConnection()
   {
     close(sockfd);
+    sockfd = -1;
   }
 
-  void Client::call(std::string method)
+  std::string Client::call(std::string method, std::vector<std::string> params)
   {
-    if (sockfd < 0)
-    {
-      throw std::runtime_error("Socket not created");
-    }
+    Client::openConnection();
 
-    Request request(0, method, {"First argument", "Another argument"});
+    Request request(msgIdCounter++, method, params);
     auto serialized = request.serialize();
     write(sockfd, serialized.c_str(), serialized.size() + 1);
 
     char buffer[1024] = {0};
     read(sockfd, buffer, 1024);
 
+    Client::closeConnection();
+
     Response response(buffer);
-    std::cout << "Received response:\n" << response.serialize() << std::endl;
+
+    if (!response.isOk())
+    {
+      throw std::runtime_error(response.getResult());
+    }
+
+    return response.getResult();
   }
 }

eRPC/Client.hpp

@@ -2,6 +2,7 @@
 #define ERPC_CLIENT_HPP
 
 #include <string>
+#include <vector>
 #include <netinet/in.h>
 
 namespace eRPC
@@ -11,13 +12,14 @@ namespace eRPC
   public:
     Client(std::string host, int port);
     ~Client();
-    void openConnection();
-    void closeConnection();
-    void call(std::string method);
+    std::string call(std::string method, std::vector<std::string> params);
   
   private:
     int sockfd;
-    sockaddr_in serv_addr;
+    sockaddr_in serverAddress;
+
+    void openConnection();
+    void closeConnection();
   };
 }
 

eRPC/Request.cpp

@@ -18,7 +18,7 @@ namespace eRPC
     std::getline(iss, line);
     if (line != "eRPC 1.0")
     {
-      throw std::runtime_error("Invalid message");
+      throw std::runtime_error("Invalid Request");
     }
 
     std::getline(iss, line);

eRPC/Response.cpp

@@ -17,7 +17,7 @@ namespace eRPC
     std::getline(iss, line);
     if (line != "eRPC 1.0")
     {
-      throw std::runtime_error("Invalid message");
+      throw std::runtime_error("Invalid Response");
     }
 
     std::getline(iss, line);

eRPC/Server.cpp

@@ -6,7 +6,6 @@
 #include <netinet/in.h>
 #include <stdexcept>
 #include <unistd.h>
-#include <iostream>
 #include <memory>
 
 namespace eRPC
@@ -32,8 +31,6 @@ namespace eRPC
     {
       throw std::runtime_error("Failed to listen on socket");
     }
-
-    std::cout << "Server listening on port " << port << std::endl;
   }
 
   Server::~Server()
@@ -52,36 +49,32 @@ namespace eRPC
 
     while (running)
     {
-      std::cout << "Waiting for connection" << std::endl;
-
-      int connfd = accept(sockfd, (sockaddr *)NULL, NULL);
+      auto connfd = accept(sockfd, (sockaddr *)NULL, NULL);
 
       char buffer[1024] = {0};
       read(connfd, buffer, 1024);
       Request request(buffer);
-      std::cout << "Received request:\n"
-                << request.serialize() << std::endl;
 
       std::unique_ptr<Response> response;
       if (methods.find(request.getMethod()) != methods.end())
       {
-        std::function<void *()> method = methods[request.getMethod()];
-        method();
+        auto method = methods[request.getMethod()];
+        auto ret = method(request.getParams());
 
         response = std::make_unique<Response>(Response(
             request.getMsgid(),
-            true,
-            "RESULTS HERE"));
+            ret.first,
+            ret.second));
       }
       else
       {
         response = std::make_unique<Response>(Response(
             request.getMsgid(),
             false,
-            "Method not found"));
+            "Method \"" + request.getMethod() + "\" not found"));
       }
 
-      std::string serialized = response->serialize();
+      auto serialized = response->serialize();
       write(connfd, serialized.c_str(), serialized.size() + 1);
 
       close(connfd);
@@ -95,7 +88,7 @@ namespace eRPC
     running = false;
   }
 
-  void Server::bindMethod(std::string method, std::function<void *()> callback)
+  void Server::bindMethod(std::string method, std::function<std::pair<bool, std::string>(std::vector<std::string>)> callback)
   {
     methods[method] = callback;
   }

eRPC/Server.hpp

@@ -33,12 +33,12 @@ namespace eRPC
     /**
      * Bind a method to a callback.
      */
-    void bindMethod(std::string method, std::function<void *()> callback);
-  
+    void bindMethod(std::string method, std::function<std::pair<bool, std::string>(std::vector<std::string>)> callback);
+
   private:
     int sockfd;
     bool running;
-    std::unordered_map<std::string, std::function<void *()>> methods;
+    std::unordered_map<std::string, std::function<std::pair<bool, std::string>(std::vector<std::string>)>> methods;
   };
 }