Add support for unidirectional and bidirectional streams with configurable stream-mode

include/bringauto/external_client/connection/communication/QuicCommunication.hpp

@@ -78,6 +78,14 @@ namespace bringauto::external_client::connection::communication {
 		void closeConnection() override;
 
 	private:
+		/// Directionality of QUIC streams created or accepted by this connection
+		enum class StreamMode {
+			/// Stream can only send data in one direction
+			Unidirectional,
+			/// Stream supports bidirectional send and receive
+			Bidirectional
+		};
+
 		/// Pointer to the MsQuic API function table
 		const QUIC_API_TABLE *quic_{nullptr};
 		/// QUIC registration handle associated with the application
@@ -98,6 +106,8 @@ namespace bringauto::external_client::connection::communication {
 		/// Path to the CA certificate file
 		std::string caFile_;
 
+		StreamMode streamMode_{StreamMode::Bidirectional};
+
 		/// Atomic state of the connection used for synchronization across threads
 		std::atomic<ConnectionState> connectionState_{ConnectionState::NOT_CONNECTED};
 
@@ -233,7 +243,7 @@ namespace bringauto::external_client::connection::communication {
 		 *
 		 * @param message Message to be sent to the peer.
 		 */
-		void sendViaQuicStream(const ExternalProtocol::ExternalClient& message);
+		void sendViaQuicStream(const ExternalProtocol::ExternalClient &message);
 
 		/**
 		 * @brief Closes the active QUIC configuration.
@@ -318,21 +328,40 @@ namespace bringauto::external_client::connection::communication {
 		/**
 		 * @brief Retrieves a protocol setting value as a plain string.
 		 *
-		 * Extracts a value from ExternalConnectionSettings::protocolSettings and
-		 * transparently handles values stored as JSON-encoded strings.
+		 * Looks up a value in ExternalConnectionSettings::protocolSettings and returns
+		 * it as a plain string. If the stored value is a JSON-encoded string, it is
+		 * transparently parsed and unwrapped.
 		 *
-		 * Allows uniform access to protocol settings regardless of whether
-		 * they were stored as plain strings or JSON-serialized values.
+		 * If the key does not exist or the value cannot be parsed as valid JSON,
+		 * the provided default value is returned and a warning is logged.
+		 *
+		 * This allows uniform access to protocol settings regardless of whether
+		 * they are stored as plain strings or JSON-serialized strings.
 		 *
 		 * @param settings External connection settings containing protocolSettings.
 		 * @param key Key identifying the protocol setting.
+		 * @param defaultValue Value returned if the key is missing or invalid.
 		 * @return Plain string value suitable for direct use (e.g. file paths).
-		 *
-		 * @throws std::out_of_range if the key is not present in protocolSettings.
 		 */
 		static std::string getProtocolSettingsString(
 			const structures::ExternalConnectionSettings &settings,
-			std::string_view key
+			std::string_view key,
+			std::string defaultValue = {}
 		);
+
+		/**
+		 * @brief Parses QUIC stream mode from protocol settings.
+		 *
+		 * Reads the stream mode from the external connection settings and determines
+		 * whether QUIC streams should be unidirectional or bidirectional.
+		 *
+		 * Supported values:
+		 *  - "unidirectional", "unidir" → Unidirectional streams
+		 *  - any other value or missing setting → Bidirectional streams (default)
+		 *
+		 * @param settings External connection settings containing QUIC protocol options
+		 * @return StreamMode Parsed stream mode (defaults to Bidirectional)
+		 */
+		static StreamMode parseStreamMode(const structures::ExternalConnectionSettings &settings);
 	};
 }

include/bringauto/settings/Constants.hpp

@@ -180,6 +180,7 @@ class Constants {
 	inline static constexpr std::string_view CLIENT_CERT { "client-cert" };
 	inline static constexpr std::string_view CLIENT_KEY { "client-key" };
 	inline static constexpr std::string_view ALPN { "alpn" };
+	inline static constexpr std::string_view STREAM_MODE { "stream-mode" };
 
 	inline static constexpr std::string_view MODULES { "modules" };
 	inline static constexpr std::string_view AERON_CONNECTION { "aeron:ipc"};

resources/config/quic_example.json

@@ -27,7 +27,9 @@
           "client-cert" : "build/certs/client.pem",
           "client-key" : "build/certs/client-key.pem",
 	      "alpn" : "sample",
-          "DisconnectTimeoutMs" : 800
+          "stream-mode": "unidirectional",
+          "DisconnectTimeoutMs" : 800,
+          "PeerUnidiStreamCount" : 100
         },
         "modules": [1,2,3]
       }

source/bringauto/external_client/connection/communication/QuicCommunication.cpp

@@ -20,7 +20,8 @@ namespace bringauto::external_client::connection::communication {
 		                                                                       settings::Constants::CLIENT_KEY)),
 	                                                                       caFile_(getProtocolSettingsString(
 		                                                                       settings,
-		                                                                       settings::Constants::CA_FILE)) {
+		                                                                       settings::Constants::CA_FILE)),
+	                                                                       streamMode_(parseStreamMode(settings)) {
 		alpnBuffer_.Buffer = reinterpret_cast<uint8_t *>(alpn_.data());
 		alpnBuffer_.Length = static_cast<uint32_t>(alpn_.size());
 
@@ -228,9 +229,15 @@ namespace bringauto::external_client::connection::communication {
 		inboundCv_.notify_one();
 	}
 
-	void QuicCommunication::sendViaQuicStream(const ExternalProtocol::ExternalClient& message) {
+	void QuicCommunication::sendViaQuicStream(const ExternalProtocol::ExternalClient &message) {
 		HQUIC stream{nullptr};
-		if (QUIC_FAILED(quic_->StreamOpen(connection_, QUIC_STREAM_OPEN_FLAG_NONE, streamCallback, this, &stream))) {
+
+		QUIC_STREAM_OPEN_FLAGS flags = streamMode_ == StreamMode::Unidirectional
+			                               ? QUIC_STREAM_OPEN_FLAG_UNIDIRECTIONAL
+			                               : QUIC_STREAM_OPEN_FLAG_NONE;
+
+		if (QUIC_FAILED(
+			quic_->StreamOpen(connection_, flags, streamCallback, this, &stream))) {
 			settings::Logger::logError("[quic] StreamOpen failed");
 			return;
 		}
@@ -290,6 +297,23 @@ namespace bringauto::external_client::connection::communication {
 				break;
 			}
 
+			/// Fired when peer open new stream on connection, stream handler need to be def
+			case QUIC_CONNECTION_EVENT_PEER_STREAM_STARTED: {
+				auto streamId = self->getStreamId(event->PEER_STREAM_STARTED.Stream);
+
+				settings::Logger::logDebug(
+					"[quic] [stream {}] Peer stream started",
+					streamId.value_or(0)
+				);
+
+				self->quic_->SetCallbackHandler(event->PEER_STREAM_STARTED.Stream,
+				                                reinterpret_cast<void *>(streamCallback), // NOSONAR - MsQuic C API requires passing function pointer as void*
+				                                context);
+
+				self->quic_->StreamReceiveSetEnabled(event->PEER_STREAM_STARTED.Stream, TRUE);
+				break;
+			}
+
 			/// Final notification that the connection has been fully shut down.
 			/// This is the last event delivered for the connection handle.
 			case QUIC_CONNECTION_EVENT_SHUTDOWN_COMPLETE: {
@@ -487,16 +511,39 @@ namespace bringauto::external_client::connection::communication {
 
 	std::string QuicCommunication::getProtocolSettingsString(
 		const structures::ExternalConnectionSettings &settings,
-		std::string_view key
+		std::string_view key,
+		std::string defaultValue
 	) {
-		const auto &raw = settings.protocolSettings.at(std::string(key));
+		const auto it = settings.protocolSettings.find(std::string(key));
+		if (it == settings.protocolSettings.end()) {
+			settings::Logger::logWarning("[quic] Protocol setting '{}' not found, using default", key);
+			return defaultValue;
+		}
+
+		const auto &raw = it->second;
 
-		if (nlohmann::json::accept(raw)) {
-			auto j = nlohmann::json::parse(raw);
-			if (j.is_string()) {
-				return j.get<std::string>();
+		try {
+			if (nlohmann::json::accept(raw)) {
+				auto j = nlohmann::json::parse(raw);
+				if (j.is_string()) {
+					return j.get<std::string>();
+				}
 			}
+			return raw;
+		} catch (const nlohmann::json::exception &) {
+			settings::Logger::logWarning("[quic] Protocol setting '{}' contains invalid JSON, using default", key);
+			return defaultValue;
 		}
-		return raw;
+	}
+
+	QuicCommunication::StreamMode QuicCommunication::parseStreamMode(
+		const structures::ExternalConnectionSettings &settings
+	) {
+		const std::string mode = getProtocolSettingsString(settings, settings::Constants::STREAM_MODE);
+
+		if (mode == "unidirectional" || mode == "unidir")
+			return StreamMode::Unidirectional;
+
+		return StreamMode::Bidirectional;
 	}
 }

source/bringauto/settings/QuicSettingsParser.cpp

@@ -29,6 +29,12 @@ namespace bringauto::settings {
 			quic.IsSet.DisconnectTimeoutMs = TRUE;
 		}
 
+		if (auto value = getOptionalUint(settings, "PeerUnidiStreamCount"); value.has_value()) {
+			settings::Logger::logDebug("[quic] [settings] PeerUnidiStreamCount settings loaded");
+			quic.PeerUnidiStreamCount = *value;
+			quic.IsSet.PeerUnidiStreamCount = TRUE;
+		}
+
 		return quic;
 	}