问题
I have a RESTServer.hpp implemented using boost.beast as shown below.
#pragma once
#include <boost/property_tree/json_parser.hpp>
#include <boost/beast/core.hpp>
#include <boost/beast/http.hpp>
#include <boost/beast/version.hpp>
#include <boost/asio.hpp>
#include <chrono>
#include <cstdlib>
#include <ctime>
#include <iostream>
#include <memory>
#include <string>
namespace beast = boost::beast;
namespace http = beast::http;
namespace net = boost::asio;
using tcp = boost::asio::ip::tcp;
class RESTServer : public std::enable_shared_from_this<RESTServer> {
public:
RESTServer(tcp::socket socket)
: m_socket(std::move(socket)) {
}
void start() {
readRequest();
checkDeadline();
}
private:
tcp::socket m_socket;
beast::flat_buffer m_buffer{8192};
http::request<http::dynamic_body> m_request;
http::response<http::dynamic_body> m_response;
net::steady_timer m_deadline{m_socket.get_executor(), std::chrono::seconds(60)};
void readRequest() {
auto self = shared_from_this();
http::async_read(m_socket, m_buffer, m_request, [self](beast::error_code ec, std::size_t bytes_transferred) {
boost::ignore_unused(bytes_transferred);
if (!ec) {
self->processRequest();
}
});
}
void processRequest() {
m_response.version(m_request.version());
m_response.keep_alive(false);
switch (m_request.method()) {
case http::verb::get:
m_response.result(http::status::ok);
m_response.set(http::field::server, "Beast");
createResponse();
break;
case http::verb::post:
m_response.result(http::status::ok);
m_response.set(http::field::server, "Beast");
createResponse();
break;
default:
m_response.result(http::status::bad_request);
m_response.set(http::field::content_type, "text/plain");
beast::ostream(m_response.body())
<< "Invalid request-method '"
<< std::string(m_request.method_string())
<< "'";
break;
}
writeResponse();
}
void createResponse() {
if(request_.target() == "/count")
{
response_.set(http::field::content_type, "text/html");
beast::ostream(response_.body())
<< "<html>\n"
<< "<head><title>Request count</title></head>\n"
<< "<body>\n"
<< "<h1>Request count</h1>\n"
<< "<p>There have been "
<< my_program_state::request_count()
<< " requests so far.</p>\n"
<< "</body>\n"
<< "</html>\n";
}
else if(request_.target() == "/time")
{
response_.set(http::field::content_type, "text/html");
beast::ostream(response_.body())
<< "<html>\n"
<< "<head><title>Current time</title></head>\n"
<< "<body>\n"
<< "<h1>Current time</h1>\n"
<< "<p>The current time is "
<< my_program_state::now()
<< " seconds since the epoch.</p>\n"
<< "</body>\n"
<< "</html>\n";
}
else
{
response_.result(http::status::not_found);
response_.set(http::field::content_type, "text/plain");
beast::ostream(response_.body()) << "File not found\r\n";
}
}
void writeResponse() {
auto self = shared_from_this();
m_response.set(http::field::content_length, m_response.body().size());
http::async_write(m_socket, m_response,
[self](beast::error_code ec, std::size_t) {
self->m_socket.shutdown(tcp::socket::shutdown_send, ec);
self->m_deadline.cancel();
});
}
void checkDeadline() {
auto self = shared_from_this();
m_deadline.async_wait([self](beast::error_code ec) {
if (!ec) {
self->m_socket.close(ec);
}
});
}
};
void httpServer(tcp::acceptor& acceptor, tcp::socket& socket) {
acceptor.async_accept(socket, [&](beast::error_code ec) {
if (!ec) {
std::make_shared<RESTServer>(std::move(socket))->start();
}
httpServer(acceptor, socket);
});
}
I also have a RESTClient RESTClient.hpp and RESTClient.cpp as shown below.
RESTClient.hpp
#pragma once
#include <boost/beast/core.hpp>
#include <boost/beast/http.hpp>
#include <boost/beast/version.hpp>
#include <boost/asio/strand.hpp>
#include <boost/property_tree/json_parser.hpp>
#include <boost/property_tree/ptree.hpp>
namespace beast = boost::beast;
namespace http = beast::http;
namespace net = boost::asio;
using tcp = boost::asio::ip::tcp;
// Performs an HTTP GET and prints the response
class RESTClient : public std::enable_shared_from_this<RESTClient> {
public:
explicit RESTClient(net::io_context& ioc);
virtual ~RESTClient();
virtual void run(char const* host, char const* port, char const* target, int version);
virtual void onResolve(beast::error_code ec, tcp::resolver::results_type results);
virtual void onConnect(beast::error_code ec, tcp::resolver::results_type::endpoint_type);
virtual void onWrite(beast::error_code ec, std::size_t bytes_transferred);
virtual void onRead(beast::error_code ec, std::size_t bytes_transferred);
private:
void createGetRequest(char const* host, char const* target, int version);
void createPostRequest(char const* host, char const* target, int version, char const *body);
std::string createBody();
tcp::resolver m_resolver;
beast::tcp_stream m_stream;
beast::flat_buffer m_buffer; // (Must persist between reads)
http::request<http::string_body> m_httpRequest;
http::response<http::string_body> m_httpResponse;
};
RESTClient.cpp
#include <boost/beast/core.hpp>
#include <boost/beast/http.hpp>
#include <boost/beast/version.hpp>
#include <boost/asio/strand.hpp>
#include <boost/lexical_cast.hpp>
#include <cstdlib>
#include <iostream>
#include <memory>
#include <string>
#include "RESTClient.hpp"
namespace beast = boost::beast;
namespace http = beast::http;
namespace net = boost::asio;
using tcp = boost::asio::ip::tcp;
void fail(beast::error_code ec, char const* what) {
std::cerr << what << ": " << ec.message() << "\n";
}
RESTClient::RESTClient(net::io_context& ioc)
: m_resolver(net::make_strand(ioc)), m_stream(net::make_strand(ioc)) {
}
RESTClient::~RESTClient() = default;
void RESTClient::run(char const* host, char const* port, char const* target, int version) {
createPostRequest(host, target, version, createBody().c_str());
m_resolver.async_resolve(host, port, beast::bind_front_handler(
&RESTClient::onResolve,
shared_from_this()));
}
void RESTClient::onResolve(beast::error_code ec, tcp::resolver::results_type results) {
if (ec) {
return fail(ec, "resolve");
}
std::cout << "onResolve ******" << std::endl;
m_stream.expires_after(std::chrono::seconds(30));
m_stream.async_connect(results, beast::bind_front_handler(
&RESTClient::onConnect,
shared_from_this()));
}
void
RESTClient::onConnect(beast::error_code ec, tcp::resolver::results_type::endpoint_type) {
if (ec) {
return fail(ec, "connect");
}
std::cout << "onConnect ******" << std::endl;
m_stream.expires_after(std::chrono::seconds(30));
http::async_write(m_stream, m_httpRequest,
beast::bind_front_handler(
&RESTClient::onWrite,
shared_from_this()));
}
void
RESTClient::onWrite(beast::error_code ec, std::size_t bytes_transferred) {
boost::ignore_unused(bytes_transferred);
if (ec) {
return fail(ec, "write");
}
std::cout << "onWrite ******" << std::endl;
http::async_read(m_stream, m_buffer, m_httpResponse, beast::bind_front_handler(
&RESTClient::onRead,
shared_from_this()));
}
void RESTClient::onRead(beast::error_code ec, std::size_t bytes_transferred) {
boost::ignore_unused(bytes_transferred);
if (ec) {
return fail(ec, "read");
}
std::cout << "onRead ******" << std::endl;
std::cout << m_httpResponse << std::endl;
m_stream.socket().shutdown(tcp::socket::shutdown_both, ec);
if (ec && ec != beast::errc::not_connected) {
return fail(ec, "shutdown");
}
}
void RESTClient::createGetRequest(char const* host, char const* target, int version) {
m_httpRequest.version(version);
m_httpRequest.method(http::verb::get);
m_httpRequest.target(target);
m_httpRequest.set(http::field::host, host);
m_httpRequest.set(http::field::user_agent, BOOST_BEAST_VERSION_STRING);
}
void RESTClient::createPostRequest(char const* host, char const* target, int version, char const* body) {
m_httpRequest.version(version);
m_httpRequest.method(http::verb::post);
m_httpRequest.target(target);
m_httpRequest.set(http::field::host, host);
m_httpRequest.set(http::field::user_agent, BOOST_BEAST_VERSION_STRING);
m_httpRequest.set(http::field::content_length, boost::lexical_cast<std::string>(strlen(body)));
m_httpRequest.set(http::field::body, body);
m_httpRequest.prepare_payload();
}
std::string RESTClient::createBody() {
boost::property_tree::ptree tree;
boost::property_tree::read_json("test.json",tree);
std::basic_stringstream<char> jsonStream;
boost::property_tree::json_parser::write_json(jsonStream, tree, false);
std::cout << "json stream :" << jsonStream.str() << std::endl;
return jsonStream.str();
}
int main(int argc, char** argv) {
// Check command line arguments.
if (argc != 4 && argc != 5) {
std::cerr <<
"Usage: http-client-async <host> <port> <target> [<HTTP version: 1.0 or 1.1(default)>]\n" <<
"Example:\n" <<
" http-client-async www.example.com 80 /\n" <<
" http-client-async www.example.com 80 / 1.0\n";
return EXIT_FAILURE;
}
auto const host = argv[1];
auto const port = argv[2];
auto const target = argv[3];
int version = argc == 5 && !std::strcmp("1.0", argv[4]) ? 10 : 11;
// The io_context is required for all I/O
net::io_context ioc;
std::cout << "version: " << version << std::endl;
// Launch the asynchronous operation
std::make_shared<RESTClient>(ioc)->run(host, port, target, version);
// Run the I/O service. The call will return when
// the get operation is complete.
ioc.run();
return EXIT_SUCCESS;
}
Now I want to test my RESTClient using googletest. In the unit test, I want to use the RESTServer to simulate the response to the client. My test class is shown below.
class MyTest : public ::testing::Test{
virtual void SetUp(){
httpServer(m_acceptor, m_socket);
m_threads.emplace_back(boost::bind(&boost::asio::io_context::run, &m_ioc));
m_ioc.run();
}
virtual void TearDown() {
for(auto& thread : m_threads) {
if(thread.joinable()) {
thread.join();
}
}
net::ip::address m_address = net::ip::make_address("0.0.0.0");
unsigned short m_port = static_cast<unsigned short>(8080);
net::io_context m_ioc{1};
tcp::acceptor m_acceptor{m_ioc, {m_address, m_port}};
tcp::socket m_socket{m_ioc};
std::vector<std::thread> m_threads;
};
My question is the following.
When I implement the class MyTest, I start the RESTServer in a separate thread. Please see the code in SetUp(). When I call m_ioc.run(), the server runs, but blocks. I would expect the server to run in a separate thread, and proceed to execute my test case, where I start the client and do some GET and POST operations.
回答1:
You're calling run in both the thread
m_threads.emplace_back(boost::bind(&boost::asio::io_context::run, &m_ioc));
and the google test thread
m_ioc.run();
which is causing the Setup to block. Try removing m_ioc.run(); since you are already spawning a thread to call io_context::run.
来源：https://stackoverflow.com/questions/60715555/io-context-run-in-a-separate-thread-blocks