Files
rest_rpc/include/async_client.hpp
T
qicosmos fa0503f156 update
2019-03-22 11:09:10 +08:00

403 lines
11 KiB
C++

#pragma once
#include <string>
#include <deque>
#include <future>
#include <boost/asio/steady_timer.hpp>
#include <boost/asio.hpp>
#include <boost/bind.hpp>
#include <boost/noncopyable.hpp>
using boost::asio::ip::tcp;
#include "client_util.hpp"
#include "const_vars.h"
#include "meta_util.hpp"
using namespace rest_rpc::rpc_service;
namespace rest_rpc {
using namespace boost::system;
class req_result {
public:
req_result() = default;
req_result(std::string_view data): data_(data) {}
bool success() const {
return !has_error(data_);
}
template<typename T>
T as() {
return get_result<T>(data_);
}
void as() {
if (has_error(data_)) {
throw std::logic_error("rpc error");
}
}
private:
std::string_view data_;
};
class async_client : private boost::noncopyable {
public:
async_client(const std::string& host, unsigned short port) : socket_(ios_), work_(ios_), strand_(ios_),
deadline_(ios_), host_(host), port_(port), body_(INIT_BUF_SIZE) {
read_buffers_[0] = boost::asio::buffer(head_);
read_buffers_[1] = boost::asio::buffer(body_);
thd_ = std::make_shared<std::thread>([this] {
ios_.run();
});
}
~async_client() {
stop();
}
void set_connect_timeout(size_t seconds) {
connect_timeout_ = seconds;
}
void set_reconnect_count(int reconnect_count) {
reconnect_cnt_ = reconnect_count;
}
void set_wait_timeout(size_t seconds) {
wait_timeout_ = seconds;
}
void connect() {
reset_deadline_timer(connect_timeout_);
auto addr = boost::asio::ip::address::from_string(host_);
socket_.async_connect({ addr, port_ }, [this](const boost::system::error_code& ec) {
if (ec) {
std::cout << ec.message() << std::endl;
has_connected_ = false;
if (reconnect_cnt_ == 0) {
return;
}
if (reconnect_cnt_ > 0) {
reconnect_cnt_--;
}
socket_ = decltype(socket_)(ios_);
connect();
}
else {
has_connected_ = true;
deadline_.cancel();
do_read();
std::cout << "connect " << host_ << " " << port_ << std::endl;
}
});
}
void set_error_callback(std::function<void(boost::system::error_code)> f) {
err_cb_ = std::move(f);
}
//sync call
template<typename T=void, typename... Args>
auto call(const std::string& rpc_name, Args&&... args) {
std::future<req_result> future = async_call(rpc_name, std::forward<Args>(args)...);
if (future.wait_for(std::chrono::seconds(wait_timeout_)) == std::future_status::timeout) {
throw std::out_of_range("timeout");
}
if constexpr (std::is_void_v<T>) {
future.get().as();
}
else {
return future.get().as<T>();
}
}
template<typename... Args>
auto async_call(const std::string& rpc_name, Args&&... args) {
req_id_++;
constexpr const size_t SIZE = sizeof...(Args);
if constexpr (sizeof...(Args) > 0) {
using last_type = last_type_of<Args...>;
if constexpr (std::is_invocable_v<last_type, boost::system::error_code, std::string_view>) {
call_with_cb(rpc_name, std::make_index_sequence<SIZE - 1>{},
std::forward_as_tuple(std::forward<Args>(args)...));
}
else {
if constexpr (sizeof...(Args) > 1){
if constexpr (std::is_invocable_v<nth_type_of<SIZE - 2, Args...>, boost::system::error_code, std::string_view>) {
call_with_cb<true>(rpc_name, std::make_index_sequence<SIZE - 2>{},
std::forward_as_tuple(std::forward<Args>(args)...));
}
}
else {
auto future = get_future();
call_impl(rpc_name, std::forward<Args>(args)...);
return future;
}
}
}
else {
auto future = get_future();
call_impl(rpc_name, std::forward<Args>(args)...);
return future;
}
}
bool has_connected() const {
return has_connected_;
}
void stop() {
if (thd_ != nullptr) {
ios_.stop();
thd_->join();
thd_ = nullptr;
}
}
private:
class call_t {
public:
call_t(boost::asio::io_service& ios, async_client* client,
uint64_t req_id, std::function<void(boost::system::error_code, std::string_view)> user_callback,
size_t timeout = 3000) : timer_(ios), client_(client), req_id_(req_id), user_callback_(std::move(user_callback)) {
timer_.expires_from_now(std::chrono::milliseconds(timeout));
timer_.async_wait([this](boost::system::error_code ec) {
if (ec) {
return;
}
has_timeout_ = true;
user_callback_(errc::make_error_code(errc::timed_out), {});
client_->erase(req_id_);
});
}
void callback(boost::system::error_code ec, std::string_view data) {
user_callback_(ec, data);
}
bool has_timeout() const {
return has_timeout_;
}
void cancel() {
boost::system::error_code ec;
timer_.cancel(ec);
}
~call_t() {
cancel();
}
private:
boost::asio::steady_timer timer_;
async_client* client_;
uint64_t req_id_;
std::function<void(boost::system::error_code, std::string_view)> user_callback_;
bool has_timeout_ = false;
};
using message_type = std::pair<std::string_view, std::uint64_t>;
void reset_deadline_timer(size_t timeout) {
deadline_.expires_from_now(boost::posix_time::seconds((long)timeout));
deadline_.async_wait([this](const boost::system::error_code& ec) {
if (!ec) {
socket_.close();
}
});
}
void write(std::uint64_t req_id, buffer_type&& message) {
size_t size = message.size();
message_type msg{ {message.release(), size}, req_id };
strand_.post([this, msg] {
outbox_.emplace_back(std::move(msg));
if (outbox_.size() > 1) {
// outstanding async_write
return;
}
this->write();
});
}
void write() {
auto& msg = outbox_[0];
size_t write_len = msg.first.length();
std::array<boost::asio::const_buffer, 3> write_buffers;
write_buffers[0] = boost::asio::buffer(&write_len, sizeof(int32_t));
write_buffers[1] = boost::asio::buffer(&msg.second, sizeof(uint64_t));
write_buffers[2] = boost::asio::buffer((char*)msg.first.data(), write_len);
boost::asio::async_write(socket_, write_buffers,
strand_.wrap([this](const boost::system::error_code& ec, const size_t length) {
::free((char*)outbox_.front().first.data());
outbox_.pop_front();
if (ec) {
if (err_cb_) err_cb_(ec);
return;
}
if (!outbox_.empty()) {
// more messages to send
this->write();
}
})
);
}
void do_read() {
std::array<boost::asio::mutable_buffer, 2> read_buffers;
read_buffers[0] = boost::asio::buffer(head_);
read_buffers[1] = boost::asio::buffer(body_);
boost::asio::async_read(socket_, read_buffers, boost::asio::transfer_at_least(HEAD_LEN),
[this](const boost::system::error_code& ec, const size_t length) {
if (!socket_.is_open()) {
//LOG(INFO) << "socket already closed";
if (err_cb_) err_cb_(errc::make_error_code(errc::connection_aborted));
return;
}
if (!ec) {
const uint32_t body_len = *((uint32_t*)(head_));
auto req_id = *((std::uint64_t*)(head_ + sizeof(int32_t)));
if (body_len == 0 || body_len > MAX_BUF_LEN) {
//LOG(INFO) << "invalid body len";
call_back(req_id, errc::make_error_code(errc::invalid_argument), {});
close();
return;
}
if (body_len > body_.size()) {
body_.resize(body_len);
read_buffers_[1] = boost::asio::buffer(body_);
read_body(req_id, length - HEAD_LEN, body_len);
return;
}
call_back(req_id, ec, { body_.data(), body_len });
do_read();
}
else {
//LOG(INFO) << ec.message();
if (err_cb_) err_cb_(ec);
close();
}
});
}
template<typename... Args>
void call_impl(const std::string& rpc_name, Args&&... args) {
msgpack_codec codec;
auto ret = codec.pack_args(rpc_name, std::forward<Args>(args)...);
write(req_id_, std::move(ret));
}
template<bool has_timeout = false, size_t... idx, typename Tuple>
void call_with_cb(const std::string& rpc_name, std::index_sequence<idx...>, Tuple&& tp) {
if constexpr (has_timeout) {
cb_map_.emplace(req_id_, std::make_unique<call_t>(ios_, this,
req_id_, std::move(std::get<sizeof...(idx)>(std::forward<Tuple>(tp))),
std::get<sizeof...(idx) + 1>(std::forward<Tuple>(tp))));
}
else {
cb_map_.emplace(req_id_, std::make_unique<call_t>(ios_, this,
req_id_, std::move(std::get<sizeof...(idx)>(std::forward<Tuple>(tp)))));
}
call_impl(rpc_name, std::get<idx>(std::forward<Tuple>(tp))...);
}
std::future<req_result> get_future() {
auto p = std::promise<req_result>();
auto future = p.get_future();
future_map_.emplace(req_id_, std::move(p));
return future;
}
void call_back(uint64_t req_id, const boost::system::error_code& ec, std::string_view data) {
if (!cb_map_.empty()) {
auto& call_helper = cb_map_[req_id];
if (call_helper && !call_helper->has_timeout()) {
call_helper->cancel();
call_helper->callback(ec, data);
}
erase(req_id);
}
else {
auto& f = future_map_[req_id];
f.set_value(req_result{data});
strand_.post([this, req_id]() { future_map_.erase(req_id); });
}
}
void erase(uint64_t req_id) {
strand_.post([this, req_id]() { cb_map_.erase(req_id); });
}
void read_body(std::uint64_t req_id, size_t start, size_t body_len) {
boost::asio::async_read(
socket_, boost::asio::buffer(body_.data() + start, body_len - start),
[this, req_id, body_len](boost::system::error_code ec, std::size_t length) {
//cancel_timer();
if (!socket_.is_open()) {
//LOG(INFO) << "socket already closed";
call_back(req_id, errc::make_error_code(errc::connection_aborted), {});
return;
}
if (!ec) {
//entier body
std::cout << length << std::endl;
call_back(req_id, ec, {body_.data(), body_len });
do_read();
}
else {
//LOG(INFO) << ec.message();
call_back(req_id, ec, {});
}
});
}
void close() {
has_connected_ = true;
if (socket_.is_open()) {
boost::system::error_code ignored_ec;
socket_.shutdown(tcp::socket::shutdown_both, ignored_ec);
socket_.close(ignored_ec);
}
}
bool has_connected_ = false;
boost::asio::io_service ios_;
tcp::socket socket_;
boost::asio::io_service::work work_;
boost::asio::io_service::strand strand_;
std::shared_ptr<std::thread> thd_ = nullptr;
std::string host_;
unsigned short port_;
size_t connect_timeout_ = 2;//s
size_t wait_timeout_ = 2;//s
int reconnect_cnt_ = -1;
boost::asio::deadline_timer deadline_;
std::deque<message_type> outbox_;
uint64_t req_id_ = 0;
std::function<void(boost::system::error_code)> err_cb_;
std::unordered_map<std::uint64_t, std::unique_ptr<call_t>> cb_map_;
std::unordered_map<std::uint64_t, std::promise<req_result>> future_map_;
char head_[HEAD_LEN] = {};
std::vector<char> body_;
std::array<boost::asio::mutable_buffer, 2> read_buffers_;
};
}