Implement call to external script and return stdout in response

lib/ProxySQL_RESTAPI_Server.cpp

@@ -15,12 +15,45 @@ using namespace httpserver;
 
 class hello_world_resource : public http_resource {
 public:
-    const std::shared_ptr<http_response> render_GET(const http_request&) {
-        return std::shared_ptr<http_response>(new string_response("GET: Hello, World!"));
+    const std::shared_ptr<http_response> render_GET(const http_request& req) {
+        return std::shared_ptr<http_response>(new string_response("GET: Hello, World!\n"));
     }
 
-    const std::shared_ptr<http_response> render(const http_request&) {
-        return std::shared_ptr<http_response>(new string_response("OTHER: Hello, World!"));
+    const std::shared_ptr<http_response> render_POST(const http_request& req) {
+        //TODO : validate json correctness in the req
+
+        int pipefd[2];
+        if (pipe(pipefd) == -1) {
+            return std::shared_ptr<http_response>(new string_response("{\"error\":\"Cannot create pipe.\"}"));
+        }
+
+		pid_t pid;
+		if ((pid=fork()) == -1) {
+			return std::shared_ptr<http_response>(new string_response("{\"error\":\"Cannot fork.\"}"));
+		}
+
+		char buf[1024];
+		if (pid == 0) {
+			dup2(pipefd[1], STDOUT_FILENO);
+			close(pipefd[0]);
+			close(pipefd[1]);
+			char* args[] = {"a", (char*)req.get_content().data(), NULL};
+			if (execve("/home/val/workspace/script.py", args, NULL) == -1) {
+				return std::shared_ptr<http_response>(new string_response("{\"error\":\"Error calling execve().\"}"));
+			}
+			exit(EXIT_SUCCESS);
+		}
+		else {
+			close(pipefd[1]);
+			int nbytes = read(pipefd[0], buf, sizeof(buf) - 1);
+			if (nbytes == -1) {
+				return std::shared_ptr<http_response>(new string_response("{\"error\":\"Error reading pipe.\"}"));
+			}
+			//TODO : validate json correctness in the buf
+			close(pipefd[0]);
+			wait(NULL);
+		}
+        return std::shared_ptr<http_response>(new string_response(buf));
     }
 };
 
@@ -34,13 +67,14 @@ ProxySQL_RESTAPI_Server::ProxySQL_RESTAPI_Server(int p) {
 
 	// for now, this is COMPLETELY DISABLED
 	// just adding a POC
-	return;
+//	return;
 
 	//ws = NULL;
 	port = p;
 	ws = new webserver(create_webserver(p));
 	//hello_world_resource hwr;
 	hr = new hello_world_resource();
+
     //ws->register_resource("/hello", &hwr);
     ws->register_resource("/hello", hr);
 	if (pthread_create(&thread_id, NULL, restapi_server_thread, ws) !=0 ) {