WebSocketApi: Implement backend for obs-websocket event listening

src/WebSocketApi.cpp

@@ -47,14 +47,19 @@ WebSocketApi::WebSocketApi()
 
 	proc_handler_add(_procHandler, "bool get_api_version(out int version)", &get_api_version, nullptr);
 	proc_handler_add(_procHandler, "bool call_request(in string request_type, in string request_data, out ptr response)",
-			 &call_request, nullptr);
+			 &call_request, this);
+	proc_handler_add(_procHandler, "bool register_event_callback(in ptr callback, out bool success)", &register_event_callback,
+			 this);
+	proc_handler_add(_procHandler, "bool unregister_event_callback(in ptr callback, out bool success)",
+			 &unregister_event_callback, this);
 	proc_handler_add(_procHandler, "bool vendor_register(in string name, out ptr vendor)", &vendor_register_cb, this);
-	proc_handler_add(_procHandler, "bool vendor_request_register(in ptr vendor, in string type, in ptr callback)",
+	proc_handler_add(_procHandler,
+			 "bool vendor_request_register(in ptr vendor, in string type, in ptr callback, out bool success)",
 			 &vendor_request_register_cb, this);
-	proc_handler_add(_procHandler, "bool vendor_request_unregister(in ptr vendor, in string type)",
+	proc_handler_add(_procHandler, "bool vendor_request_unregister(in ptr vendor, in string type, out bool success)",
 			 &vendor_request_unregister_cb, this);
-	proc_handler_add(_procHandler, "bool vendor_event_emit(in ptr vendor, in string type, in ptr data)", &vendor_event_emit_cb,
-			 this);
+	proc_handler_add(_procHandler, "bool vendor_event_emit(in ptr vendor, in string type, in ptr data, out bool success)",
+			 &vendor_event_emit_cb, this);
 
 	proc_handler_t *ph = obs_get_proc_handler();
 	assert(ph != NULL);
@@ -70,6 +75,10 @@ WebSocketApi::~WebSocketApi()
 
 	proc_handler_destroy(_procHandler);
 
+	size_t numEventCallbacks = _eventCallbacks.size();
+	_eventCallbacks.clear();
+	blog_debug("[WebSocketApi::~WebSocketApi] Deleted %ld event callbacks", numEventCallbacks);
+
 	for (auto vendor : _vendors) {
 		blog_debug("[WebSocketApi::~WebSocketApi] Deleting vendor: %s", vendor.first.c_str());
 		delete vendor.second;
@@ -80,10 +89,19 @@ WebSocketApi::~WebSocketApi()
 
 void WebSocketApi::BroadcastEvent(uint64_t requiredIntent, const std::string &eventType, const json &eventData, uint8_t rpcVersion)
 {
-	UNUSED_PARAMETER(requiredIntent);
-	UNUSED_PARAMETER(eventType);
-	UNUSED_PARAMETER(eventData);
-	UNUSED_PARAMETER(rpcVersion);
+	if (!_obsReady)
+		return;
+
+	// Only broadcast events applicable to the latest RPC version
+	if (rpcVersion && rpcVersion != CURRENT_RPC_VERSION)
+		return;
+
+	std::string eventDataString = eventData.dump();
+
+	std::shared_lock l(_mutex);
+
+	for (auto &cb : _eventCallbacks)
+		cb.callback(requiredIntent, eventType.c_str(), eventDataString.c_str(), cb.priv_data);
 }
 
 enum WebSocketApi::RequestReturnCode WebSocketApi::PerformVendorRequest(std::string vendorName, std::string requestType,
@@ -128,14 +146,27 @@ void WebSocketApi::get_api_version(void *, calldata_t *cd)
 	RETURN_SUCCESS();
 }
 
-void WebSocketApi::call_request(void *, calldata_t *cd)
+void WebSocketApi::call_request(void *priv_data, calldata_t *cd)
 {
+	auto c = static_cast<WebSocketApi *>(priv_data);
+
+#if !defined(PLUGIN_TESTS)
+	if (!c->_obsReady)
+		RETURN_FAILURE();
+#endif
+
 	const char *request_type = calldata_string(cd, "request_type");
 	const char *request_data = calldata_string(cd, "request_data");
 
 	if (!request_type)
 		RETURN_FAILURE();
 
+#ifdef PLUGIN_TESTS
+	// Allow plugin tests to complete, even though OBS wouldn't be ready at the time of the test
+	if (!c->_obsReady && std::string(request_type) != "GetVersion")
+		RETURN_FAILURE();
+#endif
+
 	auto response = static_cast<obs_websocket_request_response *>(bzalloc(sizeof(struct obs_websocket_request_response)));
 	if (!response)
 		RETURN_FAILURE();
@@ -164,6 +195,52 @@ void WebSocketApi::call_request(void *, calldata_t *cd)
 	RETURN_SUCCESS();
 }
 
+void WebSocketApi::register_event_callback(void *priv_data, calldata_t *cd)
+{
+	auto c = static_cast<WebSocketApi *>(priv_data);
+
+	void *voidCallback;
+	if (!calldata_get_ptr(cd, "callback", &voidCallback) || !voidCallback) {
+		blog(LOG_WARNING, "[WebSocketApi::register_event_callback] Failed due to missing `callback` pointer.");
+		RETURN_FAILURE();
+	}
+
+	auto cb = static_cast<obs_websocket_event_callback *>(voidCallback);
+
+	std::unique_lock l(c->_mutex);
+
+	int64_t foundIndex = c->GetEventCallbackIndex(*cb);
+	if (foundIndex != -1)
+		RETURN_FAILURE();
+
+	c->_eventCallbacks.push_back(*cb);
+
+	RETURN_SUCCESS();
+}
+
+void WebSocketApi::unregister_event_callback(void *priv_data, calldata_t *cd)
+{
+	auto c = static_cast<WebSocketApi *>(priv_data);
+
+	void *voidCallback;
+	if (!calldata_get_ptr(cd, "callback", &voidCallback) || !voidCallback) {
+		blog(LOG_WARNING, "[WebSocketApi::register_event_callback] Failed due to missing `callback` pointer.");
+		RETURN_FAILURE();
+	}
+
+	auto cb = static_cast<obs_websocket_event_callback *>(voidCallback);
+
+	std::unique_lock l(c->_mutex);
+
+	int64_t foundIndex = c->GetEventCallbackIndex(*cb);
+	if (foundIndex == -1)
+		RETURN_FAILURE();
+
+	c->_eventCallbacks.erase(c->_eventCallbacks.begin() + foundIndex);
+
+	RETURN_SUCCESS();
+}
+
 void WebSocketApi::vendor_register_cb(void *priv_data, calldata_t *cd)
 {
 	auto c = static_cast<WebSocketApi *>(priv_data);
@@ -174,7 +251,7 @@ void WebSocketApi::vendor_register_cb(void *priv_data, calldata_t *cd)
 		RETURN_FAILURE();
 	}
 
-	// Theoretically doesn't need a mutex, but it's good to be safe.
+	// Theoretically doesn't need a mutex due to module load being single-thread, but it's good to be safe.
 	std::unique_lock l(c->_mutex);
 
 	if (c->_vendors.count(vendorName)) {

src/WebSocketApi.h

@@ -57,9 +57,22 @@ class WebSocketApi {
 	inline void SetVendorEventCallback(VendorEventCallback cb) { _vendorEventCallback = cb; }
 
 private:
+	inline int64_t GetEventCallbackIndex(obs_websocket_event_callback &cb)
+	{
+		for (int64_t i = 0; i < (int64_t)_eventCallbacks.size(); i++) {
+			auto currentCb = _eventCallbacks[i];
+			if (currentCb.callback == cb.callback && currentCb.priv_data == cb.priv_data)
+				return i;
+		}
+		return -1;
+	}
+
+	// Proc handlers
 	static void get_ph_cb(void *priv_data, calldata_t *cd);
 	static void get_api_version(void *, calldata_t *cd);
 	static void call_request(void *, calldata_t *cd);
+	static void register_event_callback(void *, calldata_t *cd);
+	static void unregister_event_callback(void *, calldata_t *cd);
 	static void vendor_register_cb(void *priv_data, calldata_t *cd);
 	static void vendor_request_register_cb(void *priv_data, calldata_t *cd);
 	static void vendor_request_unregister_cb(void *priv_data, calldata_t *cd);
@@ -68,6 +81,7 @@ class WebSocketApi {
 	std::shared_mutex _mutex;
 	proc_handler_t *_procHandler;
 	std::map<std::string, Vendor *> _vendors;
+	std::vector<obs_websocket_event_callback> _eventCallbacks;
 
 	std::atomic<bool> _obsReady = false;
 

src/obs-websocket.cpp

@@ -103,12 +103,16 @@ bool obs_module_load(void)
 }
 
 #ifdef PLUGIN_TESTS
+void test_call_request();
+void test_register_event_callback();
 void test_register_vendor();
 #endif
 
 void obs_module_post_load(void)
 {
 #ifdef PLUGIN_TESTS
+	test_call_request();
+	test_register_event_callback();
 	test_register_vendor();
 #endif
 
@@ -229,12 +233,43 @@ void OnObsReady(bool ready)
 }
 
 #ifdef PLUGIN_TESTS
+void test_call_request()
+{
+	blog(LOG_INFO, "[test_call_request] Testing obs-websocket plugin API request calling...");
 
-static void test_vendor_request_cb(obs_data_t *requestData, obs_data_t *responseData, void *priv_data)
+	struct obs_websocket_request_response *response = obs_websocket_call_request("GetVersion");
+	if (response) {
+		blog(LOG_INFO, "[test_call_request] Called GetVersion. Status Code: %u | Comment: %s | Response Data: %s",
+		     response->status_code, response->comment, response->response_data);
+		obs_websocket_request_response_free(response);
+	} else {
+		blog(LOG_ERROR, "[test_call_request] Failed to call GetVersion request via obs-websocket plugin API!");
+	}
+
+	blog(LOG_INFO, "[test_call_request] Test done.");
+}
+
+static void test_event_cb(uint64_t eventIntent, const char *eventType, const char *eventData, void *priv_data)
+{
+	blog(LOG_DEBUG, "[test_event_cb] New event! Type: %s | Data: %s", eventType, eventData);
+
+	UNUSED_PARAMETER(eventIntent);
+	UNUSED_PARAMETER(priv_data);
+}
+
+void test_register_event_callback()
 {
-	blog(LOG_INFO, "[test_vendor_request_cb] Request called!");
+	blog(LOG_INFO, "[test_register_event_callback] Registering test event callback...");
+
+	if (!obs_websocket_register_event_callback(test_event_cb, nullptr))
+		blog(LOG_ERROR, "[test_register_event_callback] Failed to register event callback!");
 
-	blog(LOG_INFO, "[test_vendor_request_cb] Request data: %s", obs_data_get_json(requestData));
+	blog(LOG_INFO, "[test_register_event_callback] Test done.");
+}
+
+static void test_vendor_request_cb(obs_data_t *requestData, obs_data_t *responseData, void *priv_data)
+{
+	blog(LOG_INFO, "[test_vendor_request_cb] Request called! Request data: %s", obs_data_get_json(requestData));
 
 	// Set an item to the response data
 	obs_data_set_string(responseData, "test", "pp");
@@ -245,34 +280,25 @@ static void test_vendor_request_cb(obs_data_t *requestData, obs_data_t *response
 
 void test_register_vendor()
 {
-	blog(LOG_INFO, "[test_register_vendor] Registering test vendor...");
+	blog(LOG_INFO, "[test_register_vendor] Testing vendor registration...");
 
 	// Test plugin API version fetch
 	uint apiVersion = obs_websocket_get_api_version();
 	blog(LOG_INFO, "[test_register_vendor] obs-websocket plugin API version: %u", apiVersion);
 
-	// Test calling obs-websocket requests
-	struct obs_websocket_request_response *response = obs_websocket_call_request("GetVersion");
-	if (response) {
-		blog(LOG_INFO, "[test_register_vendor] Called GetVersion. Status Code: %u | Comment: %s | Response Data: %s",
-		     response->status_code, response->comment, response->response_data);
-		obs_websocket_request_response_free(response);
-	}
-
 	// Test vendor creation
 	auto vendor = obs_websocket_register_vendor("obs-websocket-test");
 	if (!vendor) {
-		blog(LOG_WARNING, "[test_register_vendor] Failed to create vendor!");
+		blog(LOG_ERROR, "[test_register_vendor] Failed to create vendor!");
 		return;
 	}
 
 	// Test vendor request registration
 	if (!obs_websocket_vendor_register_request(vendor, "TestRequest", test_vendor_request_cb, vendor)) {
-		blog(LOG_WARNING, "[test_register_vendor] Failed to register vendor request!");
+		blog(LOG_ERROR, "[test_register_vendor] Failed to register vendor request!");
 		return;
 	}
 
-	blog(LOG_INFO, "[test_register_vendor] Post load completed.");
+	blog(LOG_INFO, "[test_register_vendor] Test done.");
 }
-
 #endif

src/obs-websocket.h

@@ -26,6 +26,8 @@ with this program. If not, see <https://www.gnu.org/licenses/>
 #include "utils/Obs.h"
 #include "plugin-macros.generated.h"
 
+#define CURRENT_RPC_VERSION 1
+
 struct Config;
 typedef std::shared_ptr<Config> ConfigPtr;
 

src/websocketserver/WebSocketServer_Protocol.cpp

@@ -31,7 +31,7 @@ with this program. If not, see <https://www.gnu.org/licenses/>
 
 static bool IsSupportedRpcVersion(uint8_t requestedVersion)
 {
-	return (requestedVersion == 1);
+	return (requestedVersion == CURRENT_RPC_VERSION);
 }
 
 static json ConstructRequestResult(RequestResult requestResult, const json &requestJson)