keep alive setting for server and websocket improvements

test/webserver_example/websocketresponsehandler.h

@@ -0,0 +1,40 @@
+#pragma once
+
+#pragma once
+
+// system includes
+#include <string_view>
+#include <string>
+#include <system_error>
+
+// 3rdparty lib includes
+#include <asio_webserver/responsehandler.h>
+
+// forward declarations
+class ClientConnection;
+
+class WebsocketResponseHandler final : public ResponseHandler
+{
+public:
+    WebsocketResponseHandler(ClientConnection &clientConnection);
+    ~WebsocketResponseHandler() override;
+
+    void requestHeaderReceived(std::string_view key, std::string_view value) final;
+    void requestBodyReceived(std::string_view body) final;
+    void sendResponse() final;
+
+private:
+    void writtenHtmlHeader(std::error_code ec, std::size_t length);
+    void writtenHtml(std::error_code ec, std::size_t length);
+    void writtenWebsocket(std::error_code ec, std::size_t length);
+
+    ClientConnection &m_clientConnection;
+
+    std::string m_response;
+
+    bool m_connectionUpgrade{};
+    bool m_upgradeWebsocket{};
+    std::string m_secWebsocketVersion;
+    std::string m_secWebsocketKey;
+    std::string m_secWebsocketExtensions;
+};