Query the websocket to get the correct value for the ticker

.gitmodules

@@ -1,3 +1,6 @@
 [submodule "subprojects/wrenpp"]
 	path = subprojects/wrenpp
 	url = https://alarmpi.no-ip.org/gitan/King_DuckZ/wrenpp.git
+[submodule "subprojects/beast"]
+	path = subprojects/beast
+	url = https://github.com/boostorg/beast.git

meson.build

@@ -8,6 +8,8 @@ project('duckticker', 'cpp',
 full_config_dir = get_option('prefix') / get_option('sysconfdir')
 compiler_opts = ['-DWRENPP_WITH_NAME_GUESSING']
 
+beast_include = include_directories('subprojects/beast/include')
+
 subdir('src')
 
 #if meson.source_root() != full_config_dir

src/main.cpp

@@ -15,10 +15,12 @@
  * along with duckticker.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#include "nap/quick_rest.hpp"
+#include <boost/beast.hpp>
+#include <boost/asio.hpp>
 #include <simdjson.h>
 #include <wrenpp/vm_fun.hpp>
 #include <wrenpp/def_configuration.hpp>
+#include <wrenpp/callback_manager.hpp>
 #include <utility>
 
 namespace {
@@ -29,88 +31,178 @@ foreign class TickerPrice {
 
 	foreign price
 	foreign currency
+	foreign exchange
+	foreign is_valid
 }
 
 class Bitcoinity {
-	foreign static ticker(currency)
+	foreign static ticker(currency, exchange)
 }
 
 class App {
-	construct new(currency) {
+	construct new(currency, exchange) {
 		_currency = currency
+		_exchange = exchange
 	}
 
 	start() {
-		var price = Bitcoinity.ticker(_currency)
-		System.print("Ticker: %(price.price) %(price.currency)")
+		var price = Bitcoinity.ticker(_currency, _exchange)
+		System.print("Ticker: %(price.price) %(price.currency) on %(price.exchange)")
 	}
 }
 
-var the_app = App.new("USD")
+var the_app = App.new("USD", "kraken")
 )script";
 
+class WebsocketReader {
+	using tcp = boost::asio::ip::tcp;
+public:
+	WebsocketReader (std::string host,
+		const std::string& port,
+		const std::string& path,
+		const std::string& user_agent,
+		const std::string& message
+	);
+
+	~WebsocketReader();
+
+	std::string read();
+
+private:
+	boost::asio::io_context m_ioc;
+	tcp::resolver m_resolver;
+	boost::beast::websocket::stream<tcp::socket> m_ws;
+};
+
+WebsocketReader::WebsocketReader (std::string host,
+		const std::string& port,
+		const std::string& path,
+		const std::string& user_agent,
+		const std::string& message
+) :
+	m_resolver{m_ioc},
+	m_ws{m_ioc}
+{
+	//see https://www.boost.org/doc/libs/develop/libs/beast/example/websocket/client/sync/websocket_client_sync.cpp
+	const auto results = m_resolver.resolve(host, port);
+	auto ep = boost::asio::connect(m_ws.next_layer(), results);
+	host += ':' + std::to_string(ep.port());
+	m_ws.set_option(boost::beast::websocket::stream_base::decorator(
+		[user_agent](boost::beast::websocket::request_type& req)
+		{
+			req.set(boost::beast::http::field::user_agent, user_agent);
+		}
+	));
+	m_ws.handshake(host, path);
+	m_ws.write(boost::asio::buffer(message));
+}
+
+std::string WebsocketReader::read() {
+	boost::beast::flat_buffer buffer;
+	m_ws.read(buffer);
+	return boost::beast::buffers_to_string(buffer.data());
+}
+
+WebsocketReader::~WebsocketReader() {
+	m_ws.close(boost::beast::websocket::close_code::normal);
+}
+
 class TickerPrice {
 public:
 	TickerPrice() = default;
-	TickerPrice (double price, std::string&& currency) :
+	TickerPrice (double price, std::string&& currency, std::string&& exchange) :
 		m_price(price),
-		m_currency(std::move(currency))
+		m_currency(std::move(currency)),
+		m_exchange(std::move(exchange))
 	{}
 
 	void set_price (double price) { m_price = price; }
 	void set_currency (std::string&& currency) { m_currency = std::move(currency); }
+	void set_exchange (std::string&& exchange) { m_exchange = std::move(exchange); }
 	double price() const noexcept { return m_price; }
 	const char* currency() const noexcept { return m_currency.c_str(); }
+	const char* exchange() const noexcept { return m_exchange.c_str(); }
+	bool is_valid() const noexcept { return not m_exchange.empty(); }
 
 private:
 	double m_price{};
 	std::string m_currency;
+	std::string m_exchange;
 };
 
-TickerPrice ticker_price (std::string_view currency) {
-	nap::QuickRest qrest{simdjson::SIMDJSON_PADDING};
-	qrest.set_user_agent("duckticker");
-	qrest.add_post("currency", currency);
+TickerPrice ticker_price_bitoinity (std::string_view currency, std::string_view exchange) {
+	static const TickerPrice error_price {0.0, "", ""};
 
-	auto response = qrest.fetch("https://bitcoinity.org/simple_switch_currency");
-	//std::cout << response.body << '\n';
+	WebsocketReader websocket{"bitcoinity.org",
+		"80",
+		"/webs_bridge/websocket",
+		std::string(BOOST_BEAST_VERSION_STRING) + " websocket-client-coro",
+		R"({"topic":"webs:markets_)" + std::string{exchange} + "_" +
+			std::string{currency} + R"(","event":"phx_join","payload":{},"ref":"3"})"
+	};
 
 	simdjson::ondemand::parser parser;
-	simdjson::padded_string_view body{response.body, response.body.size() + simdjson::SIMDJSON_PADDING};
-	simdjson::ondemand::document doc = parser.iterate(body);
-	const double price_out = doc["price"];
-	const std::string_view currency_out = doc["currency"];
-	return {price_out, std::string{currency_out}};
+	{
+		simdjson::padded_string body = websocket.read();
+		std::cout << body << '\n';
+		if (body.size() == 0)
+			return error_price;
+		simdjson::ondemand::document doc = parser.iterate(body);
+
+		if (doc["event"].get_string().value() != "phx_reply" or doc["payload"]["status"].get_string().value() != "ok")
+			return error_price;
+	}
+
+	{
+		double price_out;
+		std::string currency_out;
+		std::string exchange_out;
+		do {
+			simdjson::padded_string body = websocket.read();
+			std::cout << body << '\n';
+			simdjson::ondemand::document doc = parser.iterate(body);
+			auto payload_result = doc["payload"];
+			if (payload_result.error())
+				return error_price;
+			simdjson::ondemand::object payload = payload_result;
+			auto data_result = payload["data"];
+			if (data_result.error())
+				return error_price;
+			simdjson::ondemand::object data = data_result;
+
+			simdjson::error_code price_error;
+			if (not data["depth"].error()) {
+				price_error = data["depth"]["price"].get(price_out);
+			}
+			else if (not data["trade"].error()) {
+				price_error = data["trade"]["price"].get(price_out);
+			}
+			else if (not data["depth_shot"].error()) {
+				continue;
+			}
+
+			std::string_view currency_out_view, exchange_out_view;
+			const auto currency_error = data["currency"].get(currency_out_view);
+			const auto exchange_error = data["exchange_name"].get(exchange_out_view);
+
+			if (price_error or currency_error or exchange_error)
+				return error_price;
+
+			currency_out = currency_out_view;
+			exchange_out = exchange_out_view;
+		} while (false);
+
+		return {price_out, std::move(currency_out), std::move(exchange_out)};
+	}
 }
 
-void ticker_price_wren (wren::VM& vm) {
+void ticker_price_bitcoinity_wren (wren::VM& vm) {
 	TickerPrice* const tp = wren::make_foreign_object<TickerPrice>(vm, "main");
-	*tp = ticker_price(wren::get<const char*>(vm, 1));
+	*tp = ticker_price_bitoinity(wren::get<const char*>(vm, 1), wren::get<const char*>(vm, 2));
 }
 
 class MyWrenConfiguration : public wren::DefConfiguration {
 public:
-	wren::foreign_method_t foreign_method_fn(
-		wren::VM* vm,
-		std::string_view module,
-		std::string_view class_name,
-		bool is_static,
-		std::string_view signature
-	) {
-		if ("main" == module) {
-			if (is_static and "Bitcoinity" == class_name and "ticker(_)" == signature) {
-				return &ticker_price_wren;
-			}
-			else if ("TickerPrice" == class_name) {
-				if (not is_static and "price" == signature)
-					return wren::make_method_bindable<&TickerPrice::price>();
-				else if (not is_static and "currency" == signature)
-					return wren::make_method_bindable<&TickerPrice::currency>();
-			}
-		}
-		return nullptr;
-	}
-
 	wren::foreign_class_t foreign_class_fn(
 		wren::VM* vm,
 		std::string_view module,
@@ -127,8 +219,14 @@ public:
 int main() {
 	MyWrenConfiguration config;
 	wren::VM vm(&config, nullptr);
-	vm.interpret("main", g_script);
+	vm.callback_manager()
+		.add_callback(true, "main", "Bitcoinity", "ticker(_,_)", &ticker_price_bitcoinity_wren)
+		.add_callback(false, "main", "TickerPrice", "price", wren::make_method_bindable<&TickerPrice::price>())
+		.add_callback(false, "main", "TickerPrice", "currency", wren::make_method_bindable<&TickerPrice::currency>())
+		.add_callback(false, "main", "TickerPrice", "is_valid", wren::make_method_bindable<&TickerPrice::is_valid>())
+		.add_callback(false, "main", "TickerPrice", "exchange", wren::make_method_bindable<&TickerPrice::exchange>());
 
+	vm.interpret("main", g_script);
 	wren::call<void>(vm, {"main", "the_app"}, "start");
 
 	return 0;

src/meson.build

@@ -10,6 +10,10 @@ wrenpp_dep = dependency('wrenpp', version: '>=0.1.1',
   default_options: ['wren_with_rand=true'],
 )
 
+boost_dep = dependency('boost', version: '>=1.78.0',
+  modules: ['coroutine', 'filesystem', 'system', 'thread'],
+)
+
 simdjson_dep = dependency('simdjson', version: '>=0.5.0',
   fallback: ['simdjson', 'simdjson_dep'],
 )
@@ -24,6 +28,10 @@ executable(meson.project_name(),
     curlcpp_dep,
     wrenpp_dep,
     simdjson_dep,
+    boost_dep,
   ],
   cpp_args: compiler_opts,
+  include_directories: [
+    beast_include,
+  ],
 )

subprojects/beast

@@ -0,0 +1 @@
+Subproject commit 9d23bec2bc523223a377582302bd28d04cb514ed

subprojects/wrenpp

@@ -1 +1 @@
-Subproject commit edd5f27ab2013e7d768fead766274b1a9eab6075
+Subproject commit d985ebc417f80c59fe26200a9e1e677f54ccb9e9