/src/crow/include/crow/http_server.h

Source (jump to first uncovered line)
#pragma once

#ifdef CROW_USE_BOOST
#include <boost/asio.hpp>
#ifdef CROW_ENABLE_SSL
#include <boost/asio/ssl.hpp>
#endif
#else
#ifndef ASIO_STANDALONE
#define ASIO_STANDALONE
#endif
#include <asio.hpp>
#ifdef CROW_ENABLE_SSL
#include <asio/ssl.hpp>
#endif
#endif

#include <atomic>
#include <chrono>
#include <cstdint>
#include <future>
#include <memory>
#include <vector>

#include "crow/version.h"
#include "crow/http_connection.h"
#include "crow/logging.h"
#include "crow/task_timer.h"


namespace crow // NOTE: Already documented in "crow/app.h"
{
#ifdef CROW_USE_BOOST
    namespace asio = boost::asio;
    using error_code = boost::system::error_code;
#else
    using error_code = asio::error_code;
#endif
    using tcp = asio::ip::tcp;

    template<typename Handler, typename Adaptor = SocketAdaptor, typename... Middlewares>
    class Server
    {
    public:
        Server(Handler* handler, std::string bindaddr, uint16_t port, std::string server_name = std::string("Crow/") + VERSION, std::tuple<Middlewares...>* middlewares = nullptr, uint16_t concurrency = 1, uint8_t timeout = 5, typename Adaptor::context* adaptor_ctx = nullptr):
          acceptor_(io_service_, tcp::endpoint(asio::ip::address::from_string(bindaddr), port)),
          signals_(io_service_),
          tick_timer_(io_service_),
          handler_(handler),
          concurrency_(concurrency),
          timeout_(timeout),
          server_name_(server_name),
          port_(port),
          bindaddr_(bindaddr),
          task_queue_length_pool_(concurrency_ - 1),
          middlewares_(middlewares),
          adaptor_ctx_(adaptor_ctx)
        {}

        void set_tick_function(std::chrono::milliseconds d, std::function<void()> f)
        {
            tick_interval_ = d;
            tick_function_ = f;
        }

        void on_tick()
        {
            tick_function_();
            tick_timer_.expires_after(std::chrono::milliseconds(tick_interval_.count()));
            tick_timer_.async_wait([this](const error_code& ec) {
                if (ec)
                    return;
                on_tick();
            });
        }

        void run()
        {
            uint16_t worker_thread_count = concurrency_ - 1;
            for (int i = 0; i < worker_thread_count; i++)
                io_service_pool_.emplace_back(new asio::io_service());
            get_cached_date_str_pool_.resize(worker_thread_count);
            task_timer_pool_.resize(worker_thread_count);

            std::vector<std::future<void>> v;
            std::atomic<int> init_count(0);
            for (uint16_t i = 0; i < worker_thread_count; i++)
                v.push_back(
                  std::async(
                    std::launch::async, [this, i, &init_count] {
                        // thread local date string get function
                        auto last = std::chrono::steady_clock::now();

                        std::string date_str;
                        auto update_date_str = [&] {
                            auto last_time_t = time(0);
                            tm my_tm;

#if defined(_MSC_VER) || defined(__MINGW32__)
                            gmtime_s(&my_tm, &last_time_t);
#else
                            gmtime_r(&last_time_t, &my_tm);
#endif
                            date_str.resize(100);
                            size_t date_str_sz = strftime(&date_str[0], 99, "%a, %d %b %Y %H:%M:%S GMT", &my_tm);
                            date_str.resize(date_str_sz);
                        };
                        update_date_str();
                        get_cached_date_str_pool_[i] = [&]() -> std::string {
                            if (std::chrono::steady_clock::now() - last >= std::chrono::seconds(1))
                            {
                                last = std::chrono::steady_clock::now();
                                update_date_str();
                            }
                            return date_str;
                        };

                        // initializing task timers
                        detail::task_timer task_timer(*io_service_pool_[i]);
                        task_timer.set_default_timeout(timeout_);
                        task_timer_pool_[i] = &task_timer;
                        task_queue_length_pool_[i] = 0;

                        init_count++;
                        while (1)
                        {
                            try
                            {
                                if (io_service_pool_[i]->run() == 0)
                                {
                                    // when io_service.run returns 0, there are no more works to do.
                                    break;
                                }
                            }
                            catch (std::exception& e)
                            {
                                CROW_LOG_ERROR << "Worker Crash: An uncaught exception occurred: " << e.what();
                            }
                        }
                    }));

            if (tick_function_ && tick_interval_.count() > 0)
            {
                tick_timer_.expires_after(std::chrono::milliseconds(tick_interval_.count()));
                tick_timer_.async_wait(
                  [this](const error_code& ec) {
                      if (ec)
                          return;
                      on_tick();
                  });
            }

            port_ = acceptor_.local_endpoint().port();
            handler_->port(port_);


            CROW_LOG_INFO << server_name_ << " server is running at " << (handler_->ssl_used() ? "https://" : "http://") << bindaddr_ << ":" << acceptor_.local_endpoint().port() << " using " << concurrency_ << " threads";
            CROW_LOG_INFO << "Call `app.loglevel(crow::LogLevel::Warning)` to hide Info level logs.";

            signals_.async_wait(
              [&](const error_code& /*error*/, int /*signal_number*/) {
                  stop();
              });

            while (worker_thread_count != init_count)
                std::this_thread::yield();

            do_accept();

            std::thread(
              [this] {
                  notify_start();
                  io_service_.run();
                  CROW_LOG_INFO << "Exiting.";
              })
              .join();
        }

        void stop()
        {
            shutting_down_ = true; // Prevent the acceptor from taking new connections
            for (auto& io_service : io_service_pool_)
            {
                if (io_service != nullptr)
                {
                    CROW_LOG_INFO << "Closing IO service " << &io_service;
                    io_service->stop(); // Close all io_services (and HTTP connections)
                }
            }

            CROW_LOG_INFO << "Closing main IO service (" << &io_service_ << ')';
            io_service_.stop(); // Close main io_service
        }

        /// Wait until the server has properly started
        void wait_for_start()
        {
            std::unique_lock<std::mutex> lock(start_mutex_);
            while (!server_started_)
                cv_started_.wait(lock);
        }

        void signal_clear()
        {
            signals_.clear();
        }

        void signal_add(int signal_number)
        {
            signals_.add(signal_number);
        }

    private:
        uint16_t pick_io_service_idx()
        {
            uint16_t min_queue_idx = 0;

            // TODO improve load balancing
            // size_t is used here to avoid the security issue https://codeql.github.com/codeql-query-help/cpp/cpp-comparison-with-wider-type/
            // even though the max value of this can be only uint16_t as concurrency is uint16_t.
            for (size_t i = 1; i < task_queue_length_pool_.size() && task_queue_length_pool_[min_queue_idx] > 0; i++)
            // No need to check other io_services if the current one has no tasks
            {
                if (task_queue_length_pool_[i] < task_queue_length_pool_[min_queue_idx])
                    min_queue_idx = i;
            }
            return min_queue_idx;
        }

        void do_accept()
        {
            if (!shutting_down_)
            {
                uint16_t service_idx = pick_io_service_idx();
                asio::io_service& is = *io_service_pool_[service_idx];
                task_queue_length_pool_[service_idx]++;
                CROW_LOG_DEBUG << &is << " {" << service_idx << "} queue length: " << task_queue_length_pool_[service_idx];

                auto p = std::make_shared<Connection<Adaptor, Handler, Middlewares...>>(
                  is, handler_, server_name_, middlewares_,
                  get_cached_date_str_pool_[service_idx], *task_timer_pool_[service_idx], adaptor_ctx_, task_queue_length_pool_[service_idx]);

                acceptor_.async_accept(
                  p->socket(),
                  [this, p, &is, service_idx](error_code ec) {
                      if (!ec)
                      {
                          is.post(
                            [p] {
                                p->start();
                            });
                      }
                      else
                      {
                          task_queue_length_pool_[service_idx]--;
                          CROW_LOG_DEBUG << &is << " {" << service_idx << "} queue length: " << task_queue_length_pool_[service_idx];
                      }
                      do_accept();
                  });
            }
        }

        /// Notify anything using `wait_for_start()` to proceed
        void notify_start()
        {
            std::unique_lock<std::mutex> lock(start_mutex_);
            server_started_ = true;
            cv_started_.notify_all();
        }

    private:
        std::vector<std::unique_ptr<asio::io_service>> io_service_pool_;
        asio::io_service io_service_;
        std::vector<detail::task_timer*> task_timer_pool_;
        std::vector<std::function<std::string()>> get_cached_date_str_pool_;
        tcp::acceptor acceptor_;
        bool shutting_down_ = false;
        bool server_started_{false};
        std::condition_variable cv_started_;
        std::mutex start_mutex_;
        asio::signal_set signals_;

        asio::basic_waitable_timer<std::chrono::high_resolution_clock> tick_timer_;

        Handler* handler_;
        uint16_t concurrency_{2};
        std::uint8_t timeout_;
        std::string server_name_;
        uint16_t port_;
        std::string bindaddr_;
        std::vector<std::atomic<unsigned int>> task_queue_length_pool_;

        std::chrono::milliseconds tick_interval_;
        std::function<void()> tick_function_;

        std::tuple<Middlewares...>* middlewares_;

        typename Adaptor::context* adaptor_ctx_;
    };
} // namespace crow

Coverage Report

Created: 2024-09-11 06:20

Line	Count	Source (jump to first uncovered line)
1		#pragma once
2
3		#ifdef CROW_USE_BOOST
4		#include <boost/asio.hpp>
5		#ifdef CROW_ENABLE_SSL
6		#include <boost/asio/ssl.hpp>
7		#endif
8		#else
9		#ifndef ASIO_STANDALONE
10		#define ASIO_STANDALONE
11		#endif
12		#include <asio.hpp>
13		#ifdef CROW_ENABLE_SSL
14		#include <asio/ssl.hpp>
15		#endif
16		#endif
17
18		#include <atomic>
19		#include <chrono>
20		#include <cstdint>
21		#include <future>
22		#include <memory>
23		#include <vector>
24
25		#include "crow/version.h"
26		#include "crow/http_connection.h"
27		#include "crow/logging.h"
28		#include "crow/task_timer.h"
29
30
31		namespace crow // NOTE: Already documented in "crow/app.h"
32		{
33		#ifdef CROW_USE_BOOST
34		namespace asio = boost::asio;
35		using error_code = boost::system::error_code;
36		#else
37		using error_code = asio::error_code;
38		#endif
39		using tcp = asio::ip::tcp;
40
41		template<typename Handler, typename Adaptor = SocketAdaptor, typename... Middlewares>
42		class Server
43		{
44		public:
45		Server(Handler* handler, std::string bindaddr, uint16_t port, std::string server_name = std::string("Crow/") + VERSION, std::tuple<Middlewares...>* middlewares = nullptr, uint16_t concurrency = 1, uint8_t timeout = 5, typename Adaptor::context* adaptor_ctx = nullptr):
46		acceptor_(io_service_, tcp::endpoint(asio::ip::address::from_string(bindaddr), port)),
47		signals_(io_service_),
48		tick_timer_(io_service_),
49		handler_(handler),
50		concurrency_(concurrency),
51		timeout_(timeout),
52		server_name_(server_name),
53		port_(port),
54		bindaddr_(bindaddr),
55		task_queue_length_pool_(concurrency_ - 1),
56		middlewares_(middlewares),
57		adaptor_ctx_(adaptor_ctx)
58	0	{}
59
60		void set_tick_function(std::chrono::milliseconds d, std::function<void()> f)
61	0	{
62	0	tick_interval_ = d;
63	0	tick_function_ = f;
64	0	}
65
66		void on_tick()
67	0	{
68	0	tick_function_();
69	0	tick_timer_.expires_after(std::chrono::milliseconds(tick_interval_.count()));
70	0	tick_timer_.async_wait([this](const error_code& ec) {
71	0	if (ec)
72	0	return;
73	0	on_tick();
74	0	});
75	0	}
76
77		void run()
78	0	{
79	0	uint16_t worker_thread_count = concurrency_ - 1;
80	0	for (int i = 0; i < worker_thread_count; i++)
81	0	io_service_pool_.emplace_back(new asio::io_service());
82	0	get_cached_date_str_pool_.resize(worker_thread_count);
83	0	task_timer_pool_.resize(worker_thread_count);
84
85	0	std::vector<std::future<void>> v;
86	0	std::atomic<int> init_count(0);
87	0	for (uint16_t i = 0; i < worker_thread_count; i++)
88	0	v.push_back(
89	0	std::async(
90	0	std::launch::async, [this, i, &init_count] {
91		// thread local date string get function
92	0	auto last = std::chrono::steady_clock::now();
93
94	0	std::string date_str;
95	0	auto update_date_str = [&] {
96	0	auto last_time_t = time(0);
97	0	tm my_tm;
98
99		#if defined(_MSC_VER) \|\| defined(__MINGW32__)
100		gmtime_s(&my_tm, &last_time_t);
101		#else
102	0	gmtime_r(&last_time_t, &my_tm);
103	0	#endif
104	0	date_str.resize(100);
105	0	size_t date_str_sz = strftime(&date_str[0], 99, "%a, %d %b %Y %H:%M:%S GMT", &my_tm);
106	0	date_str.resize(date_str_sz);
107	0	};
108	0	update_date_str();
109	0	get_cached_date_str_pool_[i] = [&]() -> std::string {
110	0	if (std::chrono::steady_clock::now() - last >= std::chrono::seconds(1))
111	0	{
112	0	last = std::chrono::steady_clock::now();
113	0	update_date_str();
114	0	}
115	0	return date_str;
116	0	};
117
118		// initializing task timers
119	0	detail::task_timer task_timer(*io_service_pool_[i]);
120	0	task_timer.set_default_timeout(timeout_);
121	0	task_timer_pool_[i] = &task_timer;
122	0	task_queue_length_pool_[i] = 0;
123
124	0	init_count++;
125	0	while (1)
126	0	{
127	0	try
128	0	{
129	0	if (io_service_pool_[i]->run() == 0)
130	0	{
131		// when io_service.run returns 0, there are no more works to do.
132	0	break;
133	0	}
134	0	}
135	0	catch (std::exception& e)
136	0	{
137	0	CROW_LOG_ERROR << "Worker Crash: An uncaught exception occurred: " << e.what();
138	0	}
139	0	}
140	0	}));
141
142	0	if (tick_function_ && tick_interval_.count() > 0)
143	0	{
144	0	tick_timer_.expires_after(std::chrono::milliseconds(tick_interval_.count()));
145	0	tick_timer_.async_wait(
146	0	[this](const error_code& ec) {
147	0	if (ec)
148	0	return;
149	0	on_tick();
150	0	});
151	0	}
152
153	0	port_ = acceptor_.local_endpoint().port();
154	0	handler_->port(port_);
155
156
157	0	CROW_LOG_INFO << server_name_ << " server is running at " << (handler_->ssl_used() ? "https://" : "http://") << bindaddr_ << ":" << acceptor_.local_endpoint().port() << " using " << concurrency_ << " threads";
158	0	CROW_LOG_INFO << "Call `app.loglevel(crow::LogLevel::Warning)` to hide Info level logs.";
159
160	0	signals_.async_wait(
161	0	[&](const error_code& /error/, int /signal_number/) {
162	0	stop();
163	0	});
164
165	0	while (worker_thread_count != init_count)
166	0	std::this_thread::yield();
167
168	0	do_accept();
169
170	0	std::thread(
171	0	[this] {
172	0	notify_start();
173	0	io_service_.run();
174	0	CROW_LOG_INFO << "Exiting.";
175	0	})
176	0	.join();
177	0	}
178
179		void stop()
180	0	{
181	0	shutting_down_ = true; // Prevent the acceptor from taking new connections
182	0	for (auto& io_service : io_service_pool_)
183	0	{
184	0	if (io_service != nullptr)
185	0	{
186	0	CROW_LOG_INFO << "Closing IO service " << &io_service;
187	0	io_service->stop(); // Close all io_services (and HTTP connections)
188	0	}
189	0	}
190
191	0	CROW_LOG_INFO << "Closing main IO service (" << &io_service_ << ')';
192	0	io_service_.stop(); // Close main io_service
193	0	}
194
195		/// Wait until the server has properly started
196		void wait_for_start()
197		{
198		std::unique_lock<std::mutex> lock(start_mutex_);
199		while (!server_started_)
200		cv_started_.wait(lock);
201		}
202
203		void signal_clear()
204		{
205		signals_.clear();
206		}
207
208		void signal_add(int signal_number)
209	0	{
210	0	signals_.add(signal_number);
211	0	}
212
213		private:
214		uint16_t pick_io_service_idx()
215	0	{
216	0	uint16_t min_queue_idx = 0;
217
218		// TODO improve load balancing
219		// size_t is used here to avoid the security issue https://codeql.github.com/codeql-query-help/cpp/cpp-comparison-with-wider-type/
220		// even though the max value of this can be only uint16_t as concurrency is uint16_t.
221	0	for (size_t i = 1; i < task_queue_length_pool_.size() && task_queue_length_pool_[min_queue_idx] > 0; i++)
222		// No need to check other io_services if the current one has no tasks
223	0	{
224	0	if (task_queue_length_pool_[i] < task_queue_length_pool_[min_queue_idx])
225	0	min_queue_idx = i;
226	0	}
227	0	return min_queue_idx;
228	0	}
229
230		void do_accept()
231	0	{
232	0	if (!shutting_down_)
233	0	{
234	0	uint16_t service_idx = pick_io_service_idx();
235	0	asio::io_service& is = *io_service_pool_[service_idx];
236	0	task_queue_length_pool_[service_idx]++;
237	0	CROW_LOG_DEBUG << &is << " {" << service_idx << "} queue length: " << task_queue_length_pool_[service_idx];
238
239	0	auto p = std::make_shared<Connection<Adaptor, Handler, Middlewares...>>(
240	0	is, handler_, server_name_, middlewares_,
241	0	get_cached_date_str_pool_[service_idx], *task_timer_pool_[service_idx], adaptor_ctx_, task_queue_length_pool_[service_idx]);
242
243	0	acceptor_.async_accept(
244	0	p->socket(),
245	0	[this, p, &is, service_idx](error_code ec) {
246	0	if (!ec)
247	0	{
248	0	is.post(
249	0	[p] {
250	0	p->start();
251	0	});
252	0	}
253	0	else
254	0	{
255	0	task_queue_length_pool_[service_idx]--;
256	0	CROW_LOG_DEBUG << &is << " {" << service_idx << "} queue length: " << task_queue_length_pool_[service_idx];
257	0	}
258	0	do_accept();
259	0	});
260	0	}
261	0	}
262
263		/// Notify anything using `wait_for_start()` to proceed
264		void notify_start()
265	0	{
266	0	std::unique_lock<std::mutex> lock(start_mutex_);
267	0	server_started_ = true;
268	0	cv_started_.notify_all();
269	0	}
270
271		private:
272		std::vector<std::unique_ptr<asio::io_service>> io_service_pool_;
273		asio::io_service io_service_;
274		std::vector<detail::task_timer*> task_timer_pool_;
275		std::vector<std::function<std::string()>> get_cached_date_str_pool_;
276		tcp::acceptor acceptor_;
277		bool shutting_down_ = false;
278		bool server_started_{false};
279		std::condition_variable cv_started_;
280		std::mutex start_mutex_;
281		asio::signal_set signals_;
282
283		asio::basic_waitable_timer<std::chrono::high_resolution_clock> tick_timer_;
284
285		Handler* handler_;
286		uint16_t concurrency_{2};
287		std::uint8_t timeout_;
288		std::string server_name_;
289		uint16_t port_;
290		std::string bindaddr_;
291		std::vector<std::atomic<unsigned int>> task_queue_length_pool_;
292
293		std::chrono::milliseconds tick_interval_;
294		std::function<void()> tick_function_;
295
296		std::tuple<Middlewares...>* middlewares_;
297
298		typename Adaptor::context* adaptor_ctx_;
299		};
300		} // namespace crow