A simple test of the experimental http_listener provided by the C++ REST SDK (Casablanca).

http_listener_test.cpp

#define _CRT_SECURE_NO_DEPRECATE

#include <cpprest/http_listener.h>
#include <iostream>
#include <iomanip>
#include <sstream>
#include <thread>
#include <chrono>
#include <ctime>

// cpprest provides macros for all streams but std::clog in basic_types.h
#ifdef _UTF16_STRINGS
// On Windows, all strings are wide
#define uclog std::wclog
#else
// On POSIX platforms, all strings are narrow
#define uclog std::clog
#endif // endif _UTF16_STRINGS

using namespace std;
using namespace web::http::experimental::listener;
using namespace web::http;
using namespace web;

void respond(const http_request& request, const status_code& status, const json::value& response) {
	json::value resp;
	resp[U("status")] = json::value::number(status);
	resp[U("response")] = response;

	// Pack in the current time for debugging purposes.
	time_t now = time(0);
	utility::stringstream_t ss;
	ss << put_time(localtime(&now), L"%Y-%m-%dT%H:%S:%MZ");
	resp[U("server_time")] = json::value::string(ss.str());

	request.reply(status, resp);
}

int main()
{
	// Synchronously bind the listener to all nics.
	uclog << U("Starting listener.") << endl;
	http_listener listener(U("http://*/json"));
	listener.open().wait();

	// Handle incoming requests.
	uclog << U("Setting up JSON listener.") << endl;
	listener.support(methods::GET, [] (http_request req) {
		auto http_get_vars = uri::split_query(req.request_uri().query());

		auto found_name = http_get_vars.find(U("request"));

		if (found_name == end(http_get_vars)) {
			auto err = U("Request received with get var \"request\" omitted from query.");
			uclog << err << endl;
			respond(req, status_codes::BadRequest, json::value::string(err));
			return;
		}

		auto request_name = found_name->second;
		uclog << U("Received request: ") << request_name << endl;
		respond(req, status_codes::OK, json::value::string(U("Request received for: ") + request_name));
	});

	// Wait while the listener does the heavy lifting.
	// TODO: Provide a way to safely terminate this loop.
	uclog << U("Waiting for incoming connection...") << endl;
	while(true) {
		this_thread::sleep_for(chrono::milliseconds(2000));
	}

	// Nothing left to do but commit suicide.
	uclog << U("Terminating JSON listener.") << endl;
	listener.close();
	return 0;
}

Does it works for IPv6 for me "listener.open().wait();" is throwing below error.

terminate called after throwing an instance of 'boost::wrapexceptboost::system::system_error'
what(): resolve: Service not found

Using address as "http://[::1]:8585"

@mpanwar-github Hmm, it seems like a couple people have reported similar behaviour.

• https://stackoverflow.com/questions/45879633/how-to-listen-on-an-ipv6-address-using-cpprestsdk-http-listener
• https://user-images.githubusercontent.com/3418587/167885315-1de2d03b-d860-44e6-9f29-f5068ae434ec.png

On my Windows box I also get an error when listening on an IPv6 address. When I listen on a wildcard address like http://*/json it listens on both IPv4 and IPv6, so that might be a workaround for you.

@SeanCline Thanks for response, I have already tried with "*" that shows port listening on IPv6. I didn't find anything if this works for IPv6 at all.

Even i tried with interface as wel this was throwing below error.

Starting listener at url.http://[fe80::a3fe:944b:534f:7ec%enp44s0f1]:8585
terminate called after throwing an instance of 'web::uri_exception'
what(): Invalid hexadecimal digit

further for me with hostname it is working not with IP "::1" that conclude that IPv6 support is there but format is different. Though i haven't done trying with other server IP with IPv6.