introduced the concept of an IPADataProcessor and removed the

ExternalClientResponseListener.h

source/w3cipa/w3cipademo/src/main.cpp

@@ -58,7 +58,7 @@ int main() {
 
     std::shared_ptr<::reference::dialog::ReferenceIPAService> ipaService =
         std::make_shared<::reference::dialog::ReferenceIPAService>(providerSelectionService);
-    providerSelectionService->addExternalClientResponseListener(ipaService);
+    providerSelectionService->addIPADataProcessorListener(ipaService);
 
 
     // Prepare the request

source/w3cipa/w3cipaframework/CMakeLists.txt

@@ -32,8 +32,8 @@ set(HEADERS
     include/w3c/voiceinteraction/ipa/ErrorMessage.h
     include/w3c/voiceinteraction/ipa/ExternalClientInput.h
     include/w3c/voiceinteraction/ipa/ExternalClientResponse.h
-    include/w3c/voiceinteraction/ipa/ExternalClientResponseListener.h
     include/w3c/voiceinteraction/ipa/IPAData.h
+    include/w3c/voiceinteraction/ipa/IPADataProcessor.h
     include/w3c/voiceinteraction/ipa/MetaData.h
     include/w3c/voiceinteraction/ipa/ModalityType.h
     include/w3c/voiceinteraction/ipa/MultiModalInput.h
@@ -66,6 +66,7 @@ set(SOURCES
     src/w3c/voiceinteraction/ipa/ErrorMessage.cpp
     src/w3c/voiceinteraction/ipa/ExternalClientResponse.cpp
     src/w3c/voiceinteraction/ipa/IPAData.cpp
+    src/w3c/voiceinteraction/ipa/IPADataProcessor.cpp
     src/w3c/voiceinteraction/ipa/MultiModalInput.cpp
     src/w3c/voiceinteraction/ipa/MultiModalInputs.cpp
     src/w3c/voiceinteraction/ipa/MultiModalOutput.cpp

source/w3cipa/w3cipaframework/include/w3c/voiceinteraction/ipa/IPAData.h

@@ -22,7 +22,6 @@ namespace w3c {
 namespace voiceinteraction {
 namespace ipa {
 
-
 /**
  * Base class for all data that is sent around through various processing
  * stages.

source/w3cipa/w3cipaframework/include/w3c/voiceinteraction/ipa/IPADataProcessor.h

@@ -0,0 +1,75 @@
+/*
+ * IPA Reference Implementation: https://github.com/w3c/voiceinteraction
+ *
+ * Copyright (C) 2024 World Wide Web Consortium. All Rights Reserved.
+ *
+ * This work is distributed under the W3C Software and Document License [1]
+ * in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even
+ * the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * [1] https://www.w3.org/Consortium/Legal/copyright-software
+ */
+
+#ifndef IPADATAPROCESSOR_H
+#define IPADATAPROCESSOR_H
+
+#include <list>
+
+#include "IPAData.h"
+
+namespace w3c {
+namespace voiceinteraction {
+namespace ipa {
+
+/**
+ * An IPA data processor is able to consume {@link IPAData}, process it
+ * and forward the processed result to registered other IPA data processors
+ * to eventually further process the data.
+ * @author Dirk Schnelle-Walka
+ */
+class IPADataProcessor {
+public:
+    /**
+     * Creates a new instance.
+     */
+    IPADataProcessor();
+
+    /**
+     * Destroys this instance.
+     */
+    virtual ~IPADataProcessor();
+
+    /**
+     * Processes the data and informs all registered listeners afterwards
+     * via {@link #notifyListeners}.
+     *
+     * Conceptually, this method can be called multiple times depending on
+     * how many other processors this instance has been subsribed to.
+     * @param data the data to process;
+     */
+    virtual void processIPAData(std::shared_ptr<IPAData> data) = 0;
+
+    /**
+     * Adds the given listener to the list of known listeners.
+     * @param listener the listener to add
+     */
+    void addIPADataProcessorListener(
+            const std::shared_ptr<IPADataProcessor>& listener);
+
+protected:
+    /**
+     * Asynchronously notifies all listeners about the processed data.
+     * @param data the processed data
+     */
+    void notifyListeners(std::shared_ptr<IPAData> data);
+
+private:
+    /** List of known listeners for processed results. */
+    std::list<std::shared_ptr<IPADataProcessor>> listeners;
+};
+
+} // namespace ipa
+} // namespace voiceinteraction
+} // namespace w3c
+
+#endif // IPADATAPROCESSOR_H

source/w3cipa/w3cipaframework/include/w3c/voiceinteraction/ipa/external/ProviderSelectionService.h

@@ -16,7 +16,7 @@
 #include <list>
 
 #include "w3c/voiceinteraction/ipa/ClientRequest.h"
-#include "w3c/voiceinteraction/ipa/ExternalClientResponseListener.h"
+#include "w3c/voiceinteraction/ipa/IPADataProcessor.h"
 #include "w3c/voiceinteraction/ipa/external/ipa/ProviderRegistry.h"
 
 using namespace w3c::voiceinteraction::ipa::external::ipa;
@@ -35,7 +35,7 @@ namespace external {
  * the list of available providers.
  * @author Dirk Schnelle-Walka
  */
-class ProviderSelectionService {
+class ProviderSelectionService : public IPADataProcessor {
 public:
     /**
      * Constructs a new object.
@@ -54,20 +54,11 @@ class ProviderSelectionService {
      */
     void processInput(const std::shared_ptr<ClientRequest>& request);
 
-    /**
-     * Adds the provided listener to the list of known external client
-     * responses.
-     * @param listener the listener to add
-     */
-    void addExternalClientResponseListener(
-        const std::shared_ptr<ExternalClientResponseListener>& listener);
+    void processIPAData(std::shared_ptr<IPAData> data);
 
 protected:
     /** The provider registry. */
     std::shared_ptr<ProviderRegistry> providerRegistry;
-
-    /** List of known listeners for externaö client responses. */
-    std::list<std::shared_ptr<ExternalClientResponseListener>> externalClientResponseListeners;
 };
 
 } // namespace external

source/w3cipa/w3cipaframework/src/w3c/voiceinteraction/ipa/IPADataProcessor.cpp

@@ -0,0 +1,44 @@
+/*
+ * IPA Reference Implementation: https://github.com/w3c/voiceinteraction
+ *
+ * Copyright (C) 2024 World Wide Web Consortium. All Rights Reserved.
+ *
+ * This work is distributed under the W3C Software and Document License [1]
+ * in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even
+ * the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * [1] https://www.w3.org/Consortium/Legal/copyright-software
+ */
+
+#include <thread>
+
+#include "w3c/voiceinteraction/ipa/IPADataProcessor.h"
+
+namespace w3c {
+namespace voiceinteraction {
+namespace ipa {
+
+IPADataProcessor::IPADataProcessor() {
+}
+
+IPADataProcessor::~IPADataProcessor() {
+}
+
+void IPADataProcessor::addIPADataProcessorListener(
+        const std::shared_ptr<IPADataProcessor>& listener) {
+    listeners.push_back(listener);
+}
+
+void IPADataProcessor::notifyListeners(std::shared_ptr<IPAData> data) {
+    for (const std::shared_ptr<IPADataProcessor>& listener : listeners) {
+        std::thread thread([&data, &listener]{
+            listener->processIPAData(data);
+        });
+        thread.join();
+    }
+}
+
+
+} // namespace ipa
+} // namespace voiceinteraction
+} // namespace w3c

source/w3cipa/w3cipaframework/src/w3c/voiceinteraction/ipa/external/ProviderSelectionService.cpp

@@ -28,11 +28,6 @@ ProviderSelectionService::ProviderSelectionService(const std::shared_ptr<Provide
 ProviderSelectionService::~ProviderSelectionService() {
 }
 
-void ProviderSelectionService::addExternalClientResponseListener(
-    const std::shared_ptr<ExternalClientResponseListener>& listener) {
-    externalClientResponseListeners.push_back(listener);
-}
-
 void ProviderSelectionService::processInput(
     const std::shared_ptr<ClientRequest>& request) {
     std::list<std::shared_ptr<ExternalClientResponse>> responses;
@@ -70,13 +65,15 @@ void ProviderSelectionService::processInput(
     }
 
     // Notify all listeners about the results.
-    for (const std::shared_ptr<ExternalClientResponseListener>& listener : externalClientResponseListeners) {
-        for (const std::shared_ptr<ExternalClientResponse>& response : responses) {
-            listener->processExternalClientResponse(response);
-        }
+    for (const std::shared_ptr<ExternalClientResponse>& response : responses) {
+        notifyListeners(response);
     }
 }
 
+void ProviderSelectionService::processIPAData(
+        std::shared_ptr<IPAData> data) {
+}
+
 } // namespace external
 } // namespace ipa
 } // namespace voiceinteraction

source/w3cipa/w3cipareferenceimplementation/include/w3c/voiceinteraction/ipa/reference/dialog/ReferenceIPAService.h

@@ -19,7 +19,7 @@
 #include <log4cplus/logger.h>
 
 #include "w3c/voiceinteraction/ipa/CombinedId.h"
-#include "w3c/voiceinteraction/ipa/ExternalClientResponseListener.h"
+#include "w3c/voiceinteraction/ipa/IPADataProcessor.h"
 #include <w3c/voiceinteraction/ipa/external/ipa/IPAService.h>
 
 using namespace w3c::voiceinteraction::ipa::external;
@@ -34,14 +34,14 @@ namespace dialog {
  * @brief A reference implementation of an IPA Service
  * @author Dirk Schnelle-Walka
  */
-class ReferenceIPAService : public IPAService, public ExternalClientResponseListener {
+class ReferenceIPAService : public IPAService, public IPADataProcessor {
 public:
     ReferenceIPAService(const std::shared_ptr<ProviderSelectionService>& service);
+
     const std::shared_ptr<ClientResponse> processInput(
         const std::shared_ptr<ClientRequest>& request);
 
-    void  processExternalClientResponse(
-        const std::shared_ptr<ExternalClientResponse>& response);
+    void processIPAData(std::shared_ptr<IPAData> data);
 
 private:
     /** Logger instance. */

source/w3cipa/w3cipareferenceimplementation/src/w3c/voiceinteraction/ipa/reference/dialog/ReferenceIPAService.cpp

@@ -98,12 +98,17 @@ const std::shared_ptr<ClientResponse> ReferenceIPAService::processInput(
     return response;
 }
 
-void  ReferenceIPAService::processExternalClientResponse(
-    const std::shared_ptr<ExternalClientResponse>& response) {
-    std::unique_lock<std::mutex> lck(mtx);
-    CombinedId combinedId(response->getSessionId(), response->getRequestId());
-    externalResponses[combinedId] = response;
-    cv.notify_one();
+void  ReferenceIPAService::processIPAData(std::shared_ptr<IPAData> data) {
+    if (std::shared_ptr<ExternalClientResponse> response =
+            std::dynamic_pointer_cast<ExternalClientResponse>(data)) {
+        std::unique_lock<std::mutex> lck(mtx);
+        CombinedId combinedId(response->getSessionId(), response->getRequestId());
+        externalResponses[combinedId] = response;
+        cv.notify_one();
+    } else {
+        LOG4CPLUS_WARN(LOGGER,
+            LOG4CPLUS_TEXT("No valid conversion for the received data"));
+    }
 }