Hello,

Would you mind sharing your code (perhaps in a git repo) so that I can reproduce, debug and advise?

No problem, the code is just a slightly modified version of the example: // // Copyright (c) 2016-2019 Vinnie Falco (vinnie dot falco at gmail dot com) // // Distributed under the Boost Software License, Version 1.0. (See accompanying // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) // // Official repository: https://github.com/boostorg/beast // //------------------------------------------------------------------------------ // // Example: HTTP server, asynchronous // //------------------------------------------------------------------------------ #include <boost/beast/core.hpp> #include <boost/beast/http.hpp> #include <boost/beast/version.hpp> #include <boost/asio/dispatch.hpp> #include <boost/asio/strand.hpp> #include <boost/asio/buffers_iterator.hpp> #include <boost/config.hpp> #include <algorithm> #include <cstdlib> #include <functional> #include <iostream> #include <memory> #include <string> #include <thread> #include <vector> namespace beast = boost::beast; // from <boost/beast.hpp> namespace http = beast::http; // from <boost/beast/http.hpp> namespace net = boost::asio; // from <boost/asio.hpp> using tcp = boost::asio::ip::tcp; // from <boost/asio/ip/tcp.hpp> // Return a reasonable mime type based on the extension of a file. beast::string_view mime_type(beast::string_view path) { using beast::iequals; auto const ext = [&path] { auto const pos = path.rfind("."); if(pos == beast::string_view::npos) return beast::string_view{}; return path.substr(pos); }(); if(iequals(ext, ".htm")) return "text/html"; if(iequals(ext, ".html")) return "text/html"; if(iequals(ext, ".php")) return "text/html"; if(iequals(ext, ".css")) return "text/css"; if(iequals(ext, ".txt")) return "text/plain"; if(iequals(ext, ".js")) return "application/javascript"; if(iequals(ext, ".json")) return "application/json"; if(iequals(ext, ".xml")) return "application/xml"; if(iequals(ext, ".swf")) return "application/x-shockwave-flash"; if(iequals(ext, ".flv")) return "video/x-flv"; if(iequals(ext, ".png")) return "image/png"; if(iequals(ext, ".jpe")) return "image/jpeg"; if(iequals(ext, ".jpeg")) return "image/jpeg"; if(iequals(ext, ".jpg")) return "image/jpeg"; if(iequals(ext, ".gif")) return "image/gif"; if(iequals(ext, ".bmp")) return "image/bmp"; if(iequals(ext, ".ico")) return "image/vnd.microsoft.icon"; if(iequals(ext, ".tiff")) return "image/tiff"; if(iequals(ext, ".tif")) return "image/tiff"; if(iequals(ext, ".svg")) return "image/svg+xml"; if(iequals(ext, ".svgz")) return "image/svg+xml"; return "application/text"; } // Append an HTTP rel-path to a local filesystem path. // The returned path is normalized for the platform. std::string path_cat( beast::string_view base, beast::string_view path) { if(base.empty()) return std::string(path); std::string result(base); #ifdef BOOST_MSVC char constexpr path_separator = '\\'; if(result.back() == path_separator) result.resize(result.size() - 1); result.append(path.data(), path.size()); for(auto& c : result) if(c == '/') c = path_separator; #else char constexpr path_separator = '/'; if(result.back() == path_separator) result.resize(result.size() - 1); result.append(path.data(), path.size()); #endif return result; } // This function produces an HTTP response for the given // request. The type of the response object depends on the // contents of the request, so the interface requires the // caller to pass a generic lambda for receiving the response. template< class Body, class Allocator, class Send> void handle_request( beast::string_view doc_root, http::request<Body, http::basic_fields<Allocator>>&& req, Send&& send) { // Returns a bad request response auto const bad_request = [&req](beast::string_view why) { http::response<http::string_body> res{http::status::bad_request, req.version()}; res.set(http::field::server, BOOST_BEAST_VERSION_STRING); res.set(http::field::content_type, "text/html"); res.keep_alive(req.keep_alive()); res.body() = std::string(why); res.prepare_payload(); return res; }; // Returns a not found response auto const not_found = [&req](beast::string_view target) { http::response<http::string_body> res{http::status::not_found, req.version()}; res.set(http::field::server, BOOST_BEAST_VERSION_STRING); res.set(http::field::content_type, "text/html"); res.keep_alive(req.keep_alive()); res.body() = "The resource '" + std::string(target) + "' was not found."; res.prepare_payload(); return res; }; // Returns a server error response auto const server_error = [&req](beast::string_view what) { http::response<http::string_body> res{http::status::internal_server_error, req.version()}; res.set(http::field::server, BOOST_BEAST_VERSION_STRING); res.set(http::field::content_type, "text/html"); res.keep_alive(req.keep_alive()); res.body() = "An error occurred: '" + std::string(what) + "'"; res.prepare_payload(); return res; }; if (req.method() == http::verb::post && req.target()=="/xxx" ) { for (const auto &h:req) printf("heder: %s=%s\n", std::string(h.name_string()).c_str(), std::string(h.value()).c_str()); printf("body as string:\n"); std::string body{ boost::asio::buffers_begin(req.body().data()), boost::asio::buffers_end(req.body().data()) }; printf("%s", body.c_str()); printf("end of body as string\n"); printf("body with iterator:\n"); const auto begin = boost::asio::buffers_begin(req.body().data()); const auto end = boost::asio::buffers_end(req.body().data()); unsigned x=0; for (auto it = begin; it != end; it++) putchar(*it); printf("end of body with iterator\n"); } // Make sure we can handle the method if( req.method() != http::verb::get && req.method() != http::verb::head) return send(bad_request("Unknown HTTP-method")); // Request path must be absolute and not contain "..". if( req.target().empty() || req.target()[0] != '/' || req.target().find("..") != beast::string_view::npos) return send(bad_request("Illegal request-target")); // Build the path to the requested file std::string path = path_cat(doc_root, req.target()); if(req.target().back() == '/') path.append("index.html"); // Attempt to open the file beast::error_code ec; http::file_body::value_type body; body.open(path.c_str(), beast::file_mode::scan, ec); // Handle the case where the file doesn't exist if(ec == beast::errc::no_such_file_or_directory) return send(not_found(req.target())); // Handle an unknown error if(ec) return send(server_error(ec.message())); // Cache the size since we need it after the move auto const size = body.size(); // Respond to HEAD request if(req.method() == http::verb::head) { http::response<http::empty_body> res{http::status::ok, req.version()}; res.set(http::field::server, BOOST_BEAST_VERSION_STRING); res.set(http::field::content_type, mime_type(path)); res.content_length(size); res.keep_alive(req.keep_alive()); return send(std::move(res)); } // Respond to GET request http::response<http::file_body> res{ std::piecewise_construct, std::make_tuple(std::move(body)), std::make_tuple(http::status::ok, req.version())}; res.set(http::field::server, BOOST_BEAST_VERSION_STRING); res.set(http::field::content_type, mime_type(path)); res.content_length(size); res.keep_alive(req.keep_alive()); return send(std::move(res)); } //------------------------------------------------------------------------------ // Report a failure void fail(beast::error_code ec, char const* what) { std::cerr << what << ": " << ec.message() << "\n"; } // Handles an HTTP server connection class session : public std::enable_shared_from_this<session> { // This is the C++11 equivalent of a generic lambda. // The function object is used to send an HTTP message. struct send_lambda { session& self_; explicit send_lambda(session& self) : self_(self) { } template<bool isRequest, class Body, class Fields> void operator()(http::message<isRequest, Body, Fields>&& msg) const { // The lifetime of the message has to extend // for the duration of the async operation so // we use a shared_ptr to manage it. auto sp = std::make_shared< http::message<isRequest, Body, Fields>>(std::move(msg)); // Store a type-erased version of the shared // pointer in the class to keep it alive. self_.res_ = sp; // Write the response http::async_write( self_.stream_, *sp, beast::bind_front_handler( &session::on_write, self_.shared_from_this(), sp->need_eof())); } }; beast::tcp_stream stream_; beast::flat_buffer buffer_; std::shared_ptr<std::string const> doc_root_; // http::request<http::string_body> req_; http::request<http::dynamic_body> req_; std::shared_ptr<void> res_; send_lambda lambda_; public: // Take ownership of the stream session( tcp::socket&& socket, std::shared_ptr<std::string const> const& doc_root) : stream_(std::move(socket)) , doc_root_(doc_root) , lambda_(*this) { } // Start the asynchronous operation void run() { // We need to be executing within a strand to perform async operations // on the I/O objects in this session. Although not strictly necessary // for single-threaded contexts, this example code is written to be // thread-safe by default. net::dispatch(stream_.get_executor(), beast::bind_front_handler( &session::do_read, shared_from_this())); } void do_read() { // Make the request empty before reading, // otherwise the operation behavior is undefined. req_ = {}; // Set the timeout. stream_.expires_after(std::chrono::seconds(30)); // Read a request http::async_read(stream_, buffer_, req_, beast::bind_front_handler( &session::on_read, shared_from_this())); } void on_read( beast::error_code ec, std::size_t bytes_transferred) { boost::ignore_unused(bytes_transferred); // This means they closed the connection if(ec == http::error::end_of_stream) return do_close(); if(ec) return fail(ec, "read"); // Send the response handle_request(*doc_root_, std::move(req_), lambda_); } void on_write( bool close, beast::error_code ec, std::size_t bytes_transferred) { boost::ignore_unused(bytes_transferred); if(ec) return fail(ec, "write"); if(close) { // This means we should close the connection, usually because // the response indicated the "Connection: close" semantic. return do_close(); } // We're done with the response so delete it res_ = nullptr; // Read another request do_read(); } void do_close() { // Send a TCP shutdown beast::error_code ec; stream_.socket().shutdown(tcp::socket::shutdown_send, ec); // At this point the connection is closed gracefully } }; //------------------------------------------------------------------------------ // Accepts incoming connections and launches the sessions class listener : public std::enable_shared_from_this<listener> { net::io_context& ioc_; tcp::acceptor acceptor_; std::shared_ptr<std::string const> doc_root_; public: listener( net::io_context& ioc, tcp::endpoint endpoint, std::shared_ptr<std::string const> const& doc_root) : ioc_(ioc) , acceptor_(net::make_strand(ioc)) , doc_root_(doc_root) { beast::error_code ec; // Open the acceptor acceptor_.open(endpoint.protocol(), ec); if(ec) { fail(ec, "open"); return; } // Allow address reuse acceptor_.set_option(net::socket_base::reuse_address(true), ec); if(ec) { fail(ec, "set_option"); return; } // Bind to the server address acceptor_.bind(endpoint, ec); if(ec) { fail(ec, "bind"); return; } // Start listening for connections acceptor_.listen( net::socket_base::max_listen_connections, ec); if(ec) { fail(ec, "listen"); return; } } // Start accepting incoming connections void run() { do_accept(); } private: void do_accept() { // The new connection gets its own strand acceptor_.async_accept( net::make_strand(ioc_), beast::bind_front_handler( &listener::on_accept, shared_from_this())); } void on_accept(beast::error_code ec, tcp::socket socket) { if(ec) { fail(ec, "accept"); } else { // Create the session and run it std::make_shared<session>( std::move(socket), doc_root_)->run(); } // Accept another connection do_accept(); } }; //------------------------------------------------------------------------------ int main(int argc, char* argv[]) { // Check command line arguments. if (argc != 4) { std::cerr << "Usage: http-server-async <address> <port> <doc_root>\n" << "Example:\n" << " http-server-async 0.0.0.0 8080 .\n"; return EXIT_FAILURE; } auto const address = net::ip::make_address(argv[1]); auto const port = static_cast<unsigned short>(std::atoi(argv[2])); auto const doc_root = std::make_shared<std::string>(argv[3]); // The io_context is required for all I/O net::io_context ioc; // Create and launch a listening port std::make_shared<listener>( ioc, tcp::endpoint{address, port}, doc_root)->run(); // Run the I/O service printf("running\n"); ioc.run(); return EXIT_SUCCESS; } And this is my index.html: <?xml version="1.0" encoding="utf-8"?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd> <html xmlns=http://www.w3.org/1999/xhtml> <body> <form action="xxx" method="post" accept-charset="utf-8" enctype="multipart/form-data"> <label for="field0">field 0:</label><input type="text" id="field0" name="field0"/><br/><br/> <label for="field1">field 1:</label><input type="password" id="field1" name="field1"/><br/><br/> <label for="field2">field 2:</label><input type="text" id="field2" name="field2"/><br/><br/> <label for="field3">field 3:</label><input type="text" id="field3" name="field3"/><br/><br/> <label for="field4">field 4:</label><input type="file" id="field4" name="field4"/><br/><br/> <input type="submit" value="Submit"/> </form> </body> </html> Klebsch Mario Funktion | R&D Tel: +49 (0) 531 38 701 718 Raum: Braunschweig, E20 Diese E-Mail und die an sie angehängten Dateien sind ausschließlich für Personen oder Institutionen bestimmt, deren Namen oben aufgeführt sind. 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