Add gRPC mode switching

examples/quickstart-cpp/src/main.cc

@@ -2,10 +2,17 @@
 #include "start.h"
 
 int main(int argc, char **argv) {
-  if (argc != 3) {
-    std::cout << "Client takes three arguments as follows: " << std::endl;
-    std::cout << "./client  CLIENT_ID  SERVER_URL" << std::endl;
-    std::cout << "Example: ./flwr_client 0 '127.0.0.1:8080'" << std::endl;
+  if (argc != 3 && argc != 4) {
+    std::cout << "Client takes three mandatory arguments and one optional as "
+                 "follows: "
+              << std::endl;
+    std::cout << "./client  CLIENT_ID  SERVER_URL [GRPC_MODE]" << std::endl;
+    std::cout
+        << "GRPC_MODE is optional and can be either 'bidi' (default) or 'rere'."
+        << std::endl;
+    std::cout << "Example: ./flwr_client 0 '127.0.0.1:8080' bidi" << std::endl;
+    std::cout << "This is the same as: ./flwr_client 0 '127.0.0.1:8080'"
+              << std::endl;
     return 0;
   }
 
@@ -38,9 +45,15 @@ int main(int argc, char **argv) {
   // Define a server address
   std::string server_add = SERVER_URL;
 
-  // Start client
-  // start::start_client(server_add, &client);
-  start::start_rere_client(server_add, &client);
+  if (argc == 4 && std::string(argv[3]) == "rere") {
+    std::cout << "Starting rere client" << std::endl;
+    // Start rere client
+    start::start_rere_client(server_add, &client);
+  } else {
+    std::cout << "Starting bidi client" << std::endl;
+    // Start bidi client
+    start::start_client(server_add, &client);
+  }
 
   return 0;
 }