Improvements in the examples.

examples/basic3.cpp

@@ -0,0 +1,80 @@
+/* Copyright (c) 2019 - 2021 Marcelo Zimbres Silva (mzimbres at gmail dot com)
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#include <iostream>
+
+#include <aedis/aedis.hpp>
+
+#include "types.hpp"
+#include "utils.ipp"
+
+using namespace aedis;
+
+/* A more elaborate way sending requests where a new request is sent
+ * only after the last one has arrived. This can be used as a starting
+ * point for more complex applications.
+ *
+ * We also separate the application logic out out the coroutine for
+ * clarity.
+ */
+
+// Adds a new element in the queue if necessary.
+void prepare_next(std::queue<resp3::request>& reqs)
+{
+   if (std::empty(reqs) || std::size(reqs) == 1)
+      reqs.push({});
+}
+
+void process_response(
+   std::queue<resp3::request>& requests,
+   resp3::response& resp)
+{
+   std::cout
+      << requests.front().commands.front() << ":\n"
+      << resp << std::endl;
+
+   switch (requests.front().commands.front()) {
+      case command::hello:
+         prepare_next(requests);
+         requests.back().push(command::ping);
+         break;
+      case command::ping:
+         prepare_next(requests);
+         requests.back().push(command::quit);
+         break;
+      default: {};
+   }
+}
+
+net::awaitable<void> ping()
+{
+   auto socket = co_await make_connection();
+   resp3::stream<tcp_socket> stream{std::move(socket)};
+
+   std::queue<resp3::request> requests;
+   requests.push({});
+   requests.back().push(command::hello, 3);
+
+   while (!std::empty(requests)) {
+      co_await stream.async_write(requests.front());
+      while (!std::empty(requests.front().commands)) {
+         resp3::response resp;
+         co_await stream.async_read(resp);
+         process_response(requests, resp);
+         requests.front().commands.pop();
+      }
+
+      requests.pop();
+   }
+}
+
+int main()
+{
+   net::io_context ioc;
+   co_spawn(ioc, ping(), net::detached);
+   ioc.run();
+}