add simple signaling-server implemented using libdatachannel cpp-api

CMakeLists.txt

@@ -588,6 +588,7 @@ if(NOT NO_EXAMPLES)
 	if(NOT NO_WEBSOCKET)
 		add_subdirectory(examples/client)
 		add_subdirectory(examples/client-benchmark)
+		add_subdirectory(examples/signaling-server-libdatachannel-ws)
 	endif()
 	if(NOT NO_MEDIA)
 		add_subdirectory(examples/media-receiver)

examples/signaling-server-libdatachannel-ws/CMakeLists.txt

@@ -0,0 +1,38 @@
+cmake_minimum_required(VERSION 3.15)
+project(signaling-server-libdatachannel-ws
+	VERSION 0.1
+	LANGUAGES CXX)
+
+	set(MEDIA_UWP_RESOURCES
+	uwp/Logo.png
+	uwp/package.appxManifest
+	uwp/SmallLogo.png
+	uwp/SmallLogo44x44.png
+	uwp/SplashScreen.png
+	uwp/StoreLogo.png
+	uwp/Windows_TemporaryKey.pfx
+)
+
+if(CMAKE_SYSTEM_NAME STREQUAL "WindowsStore")
+	add_executable(signaling-server-libdatachannel-ws signaling-server.cpp ${MEDIA_UWP_RESOURCES})
+else()
+	add_executable(signaling-server-libdatachannel-ws signaling-server.cpp)
+endif()
+
+set_target_properties(signaling-server-libdatachannel-ws PROPERTIES
+	CXX_STANDARD 17
+	OUTPUT_NAME signaling-server)
+
+set_target_properties(signaling-server-libdatachannel-ws PROPERTIES
+	XCODE_ATTRIBUTE_PRODUCT_BUNDLE_IDENTIFIER com.github.paullouisageneau.libdatachannel.examples.signaling-server-libdatachannel-ws)
+
+find_package(Threads REQUIRED)
+target_link_libraries(signaling-server-libdatachannel-ws LibDataChannel::LibDataChannel Threads::Threads nlohmann_json::nlohmann_json)
+
+if(MSVC)
+	add_custom_command(TARGET signaling-server-libdatachannel-ws POST_BUILD
+		COMMAND ${CMAKE_COMMAND} -E copy_if_different
+		"$<TARGET_FILE_DIR:datachannel>/datachannel.dll"
+		$<TARGET_FILE_DIR:signaling-server-libdatachannel-ws>
+	)
+endif()

examples/signaling-server-libdatachannel-ws/signaling-server.cpp

@@ -0,0 +1,162 @@
+/**
+ * signaling server example for libdatachannel
+ * Copyright (c) 2024 Tim Schneider
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#include "rtc/rtc.hpp"
+
+#include <csignal>
+#include <iostream>
+#include <memory>
+#include <string>
+#include <thread>
+#include <unordered_map>
+
+#include <nlohmann/json.hpp>
+using nlohmann::json;
+
+
+using namespace std::chrono_literals;
+using std::shared_ptr;
+using std::weak_ptr;
+template <class T> weak_ptr<T> make_weak_ptr(shared_ptr<T> ptr) { return ptr; }
+
+std::string get_user(weak_ptr<rtc::WebSocket> wws) {
+	const auto &ws = wws.lock();
+	const auto path_ = ws->path().value();
+	const auto user = path_.substr(path_.rfind('/') + 1);
+	return user;
+}
+
+void signalHandler(int signum) {
+	std::cout << "Interrupt signal (" << signum << ") received.\n";
+	// terminate program
+	exit(signum);
+}
+
+int main(int argc, char *argv[]) {
+	rtc::WebSocketServerConfiguration config;
+	config.port = 8000;
+	config.enableTls = false;
+	config.certificatePemFile = std::nullopt;
+	config.keyPemFile = std::nullopt;
+	config.keyPemPass = std::nullopt;
+	config.bindAddress = std::nullopt;
+	config.connectionTimeout = std::nullopt;
+
+	// Check command line arguments.
+	for (int i = 1; i < argc; i++) {
+		if (strcmp(argv[i], "--help") == 0) {
+			const size_t len = strlen(argv[0]);
+			char *path = (char *)malloc(len + 1);
+			strcpy(path, argv[0]);
+			path[len] = 0;
+
+			char *app_name = NULL;
+			// app_name = last_path_segment(path, "\\/");
+			fprintf(stderr,
+			        "Usage: %s [-p <port>] [-a <bind-address>] [--connection-timeout <timeout>] "
+			        "[--enable-tls] [--certificatePemFile <file>] [--keyPemFile <keyPemFile>] "
+			        "[--keyPemPass <pass>]\n"
+			        "Example:\n"
+			        "    %s -p 8000 -a 127.0.0.1 \n",
+			        app_name, app_name);
+			free(path);
+			return EXIT_FAILURE;
+		}
+		if (strcmp(argv[i], "-p") == 0) {
+			config.port = atoi(argv[++i]);
+			continue;
+		}
+		if (strcmp(argv[i], "-a") == 0) {
+			config.bindAddress = argv[++i];
+			continue;
+		}
+		if (strcmp(argv[i], "--connection-timeout") == 0) {
+			config.connectionTimeout = std::chrono::milliseconds(atoi(argv[++i]));
+			continue;
+		}
+		if (strcmp(argv[i], "--enable-tls") == 0) {
+			config.enableTls = true;
+			continue;
+		}
+		if (strcmp(argv[i], "--certificatePemFile") == 0) {
+			config.certificatePemFile = argv[++i];
+			continue;
+		}
+		if (strcmp(argv[i], "--keyPemFile") == 0) {
+			config.keyPemFile = argv[++i];
+			continue;
+		}
+		if (strcmp(argv[i], "--keyPemPass") == 0) {
+			config.keyPemPass = argv[++i];
+			continue;
+		}
+	}
+
+	auto wss = std::make_shared<rtc::WebSocketServer>(config);
+	std::unordered_map<std::string, std::shared_ptr<rtc::WebSocket>> clients_map;
+
+	wss->onClient([&clients_map](std::shared_ptr<rtc::WebSocket> ws) {
+		std::promise<void> wsPromise;
+		auto wsFuture = wsPromise.get_future();
+		std::cout << "WebSocket client (remote-address: " << ws->remoteAddress().value() << ")"
+		          << std::endl;
+
+		ws->onOpen([&clients_map, &wsPromise, wws = make_weak_ptr(ws)]() {
+			const auto user = get_user(wws);
+			std::cout << "WebSocket connected (user: " << user << ")" << std::endl;
+			clients_map.insert_or_assign(user, wws.lock());
+			wsPromise.set_value();
+		});
+		ws->onError([&clients_map, &wsPromise, wws = make_weak_ptr(ws)](std::string s) {
+			wsPromise.set_exception(std::make_exception_ptr(std::runtime_error(s)));
+			const auto user = get_user(wws);
+			std::cout << "WebSocket error (user: " << user << ")" << std::endl;
+			clients_map.erase(user);
+		});
+		ws->onClosed([&clients_map, &wsPromise, wws = make_weak_ptr(ws)]() {
+			const auto user = get_user(wws);
+			std::cout << "WebSocket closed (user: " << user << ")" << std::endl;
+			clients_map.erase(user);
+		});
+		ws->onMessage([&clients_map, wws = make_weak_ptr(ws)](auto data) {
+			// data holds either std::string or rtc::binary
+			if (!std::holds_alternative<std::string>(data))
+				return;
+
+			json message = json::parse(std::get<std::string>(data));
+
+			auto it = message.find("id");
+			if (it == message.end())
+				return;
+
+			auto id = it->get<std::string>();
+
+			auto client_dst = clients_map.find(id);
+			if (client_dst == clients_map.end()) {
+				std::cout << "not found" << std::endl;
+			} else {
+				const auto user = get_user(wws);
+
+				message["id"] = user;
+				auto &[id_dst, ws_dst] = *client_dst;
+				std::cout << user << "->" << id << ": " << message.dump() << std::endl;
+				ws_dst->send(message.dump());
+			}
+		});
+		std::cout << "Waiting for client to be connected..." << std::endl;
+		wsFuture.get();
+	});
+
+	signal(SIGINT, signalHandler);
+	while (true) {
+		std::this_thread::sleep_for(1s);
+	}
+
+	return EXIT_SUCCESS;
+}

examples/signaling-server-libdatachannel-ws/uwp/package.appxManifest

@@ -0,0 +1,42 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Package
+	xmlns="http://schemas.microsoft.com/appx/manifest/foundation/windows10"
+    xmlns:mp="http://schemas.microsoft.com/appx/2014/phone/manifest"
+	xmlns:uap="http://schemas.microsoft.com/appx/manifest/uap/windows10"
+	xmlns:desktop4="http://schemas.microsoft.com/appx/manifest/desktop/windows10/4"
+	xmlns:iot2="http://schemas.microsoft.com/appx/manifest/iot/windows10/2"
+	IgnorableNamespaces="uap mp">
+
+	<Identity Name="274EF42C-A3FB-3D6C-B127-E39C508A4F0E" Publisher="CN=CMake" Version="1.0.0.0" />
+	<mp:PhoneIdentity PhoneProductId="274EF42C-A3FB-3D6C-B127-E39C508A4F0E" PhonePublisherId="00000000-0000-0000-0000-000000000000"/>
+	<Properties>
+		<DisplayName>signaling-server-libdatachannel-ws</DisplayName>
+		<PublisherDisplayName>CMake</PublisherDisplayName>
+		<Logo>StoreLogo.png</Logo>
+	</Properties>
+	<Dependencies>
+		<TargetDeviceFamily Name="Windows.Universal" MinVersion="10.0.0.0" MaxVersionTested="10.0.0.0" />
+	</Dependencies>
+	<Resources>
+		<Resource Language="x-generate" />
+	</Resources>
+	<Applications>
+		<Application 
+			Id="App"
+			Executable="signaling-server.exe"
+			EntryPoint="signaling-server-libdatachannel-ws.App"
+			desktop4:Subsystem="console"
+			desktop4:SupportsMultipleInstances="true"
+			iot2:Subsystem="console"
+			iot2:SupportsMultipleInstances="true">
+			<uap:VisualElements
+				DisplayName="signaling-server-libdatachannel-ws"
+				Description="signaling-server-libdatachannel-ws"
+				BackgroundColor="#336699"
+				Square150x150Logo="Logo.png"
+				Square44x44Logo="SmallLogo44x44.png">
+				<uap:SplashScreen Image="SplashScreen.png" />
+			</uap:VisualElements>
+		</Application>
+	</Applications>
+</Package>