refactor: Coroutine based webserver (#1699)

Code of new coroutine-based web server. The new server is not connected
to Clio and not ready to use yet.
For #919.

tests/common/util/TestWebSocketClient.hpp

@@ -0,0 +1,94 @@
+//------------------------------------------------------------------------------
+/*
+    This file is part of clio: https://github.com/XRPLF/clio
+    Copyright (c) 2023, the clio developers.
+
+    Permission to use, copy, modify, and distribute this software for any
+    purpose with or without fee is hereby granted, provided that the above
+    copyright notice and this permission notice appear in all copies.
+
+    THE  SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+    WITH  REGARD  TO  THIS  SOFTWARE  INCLUDING  ALL  IMPLIED  WARRANTIES  OF
+    MERCHANTABILITY  AND  FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+    ANY  SPECIAL,  DIRECT,  INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+    WHATSOEVER  RESULTING  FROM  LOSS  OF USE, DATA OR PROFITS, WHETHER IN AN
+    ACTION  OF  CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+*/
+//==============================================================================
+
+#pragma once
+
+#include "util/TestHttpClient.hpp"
+
+#include <boost/asio/io_context.hpp>
+#include <boost/asio/ip/tcp.hpp>
+#include <boost/asio/spawn.hpp>
+#include <boost/beast/core/tcp_stream.hpp>
+#include <boost/beast/ssl/ssl_stream.hpp>
+#include <boost/beast/websocket/stream.hpp>
+
+#include <chrono>
+#include <optional>
+#include <string>
+#include <string_view>
+#include <vector>
+
+class WebSocketSyncClient {
+    boost::asio::io_context ioc_;
+    boost::asio::ip::tcp::resolver resolver_{ioc_};
+    boost::beast::websocket::stream<boost::asio::ip::tcp::socket> ws_{ioc_};
+
+public:
+    void
+    connect(std::string const& host, std::string const& port, std::vector<WebHeader> additionalHeaders = {});
+
+    void
+    disconnect();
+
+    std::string
+    syncPost(std::string const& body);
+};
+
+class WebSocketAsyncClient {
+    boost::beast::websocket::stream<boost::beast::tcp_stream> stream_;
+
+public:
+    WebSocketAsyncClient(boost::asio::io_context& ioContext);
+
+    std::optional<boost::system::error_code>
+    connect(
+        std::string const& host,
+        std::string const& port,
+        boost::asio::yield_context yield,
+        std::chrono::steady_clock::duration timeout,
+        std::vector<WebHeader> additionalHeaders = {}
+    );
+
+    std::optional<boost::system::error_code>
+    send(boost::asio::yield_context yield, std::string_view message, std::chrono::steady_clock::duration timeout);
+
+    std::expected<std::string, boost::system::error_code>
+    receive(boost::asio::yield_context yield, std::chrono::steady_clock::duration timeout);
+
+    void
+    gracefulClose(boost::asio::yield_context yield, std::chrono::steady_clock::duration timeout);
+
+    void
+    close();
+};
+
+class WebServerSslSyncClient {
+    boost::asio::io_context ioc_;
+    std::optional<boost::beast::websocket::stream<boost::beast::ssl_stream<boost::asio::ip::tcp::socket>>> ws_;
+
+public:
+    void
+    connect(std::string const& host, std::string const& port);
+
+    void
+    disconnect();
+
+    std::string
+    syncPost(std::string const& body);
+};