Missing files.

examples/custom_response1.cpp

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+/* 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 <string>
+#include <iostream>
+#include <charconv>
+
+#include <aedis/aedis.hpp>
+
+#include "types.hpp"
+#include "utils.ipp"
+
+using aedis::command;
+using aedis::resp3::type;
+using aedis::resp3::request;
+using aedis::resp3::response;
+using aedis::resp3::async_read;
+using aedis::resp3::response_base;
+
+namespace net = aedis::net;
+
+/** Illustrates how to write a custom response.  Useful to users
+ *  seeking to improve performance and reduce latency.
+ */
+
+
+/** A response that parses the result of a response directly in an int
+ *  variable. The same reasoning can be applied for keys containing
+ *  e.g. json strings.
+ *
+ */
+struct response_int : response_base {
+   int result;
+
+   void
+   add(type t,
+       std::size_t aggregate_size,
+       std::size_t depth,
+       char const* data,
+       std::size_t data_size) override
+   {
+      auto r = std::from_chars(data, data + data_size, result);
+      if (r.ec == std::errc::invalid_argument)
+         throw std::runtime_error("from_chars: Unable to convert");
+   }
+};
+
+/// To ignore the reponse of a command use the response base class.
+using response_ignore = response_base;
+
+/** This coroutine avoids reading the response to a get command in a
+ *  temporary buffer by using a custom response. This is always
+ *  possible when the application knows the data type being stored in
+ *  a specific key.
+ */
+net::awaitable<void> example()
+{
+   try {
+      request req;
+      req.push(command::hello, 3);
+
+      req.push(command::set, "key", 42);
+      req.push(command::get, "key");
+      req.push(command::quit);
+
+      auto socket = co_await make_connection("127.0.0.1", "6379");
+      co_await async_write(socket, req);
+
+      std::string buffer;
+      response_ignore ignore;
+
+      // hello
+      co_await async_read(socket, buffer, ignore);
+
+      // set
+      co_await async_read(socket, buffer, ignore);
+
+      // get
+      response_int int_resp;
+      co_await async_read(socket, buffer, int_resp);
+
+      std::cout << int_resp.result << std::endl;
+
+      // quit.
+      co_await async_read(socket, buffer, ignore);
+
+   } catch (std::exception const& e) {
+      std::cerr << e.what() << std::endl;
+   }
+}
+
+int main()
+{
+   net::io_context ioc;
+   co_spawn(ioc, example(), net::detached);
+   ioc.run();
+}