AP-25000: Introduce two separate aspects of 'view data' for python nodes

* backend view data: received from/provided to the python side; to be
  able to properly restore the Agent Chat Widget data service state and
  output data on re-execution
* frontend view data: received from/provided to the frontend to be able
  to properly restore the chat on initialization

AP-25000 (Agent Chat View to output conversation - base version)

Author: hornm-knime

org.knime.python3.nodes/src/main/java/org/knime/python3/nodes/CloseablePythonNodeProxy.java

@@ -99,6 +99,7 @@
 import org.knime.python3.arrow.PythonArrowDataUtils;
 import org.knime.python3.arrow.PythonArrowTableConverter;
 import org.knime.python3.nodes.CloseablePythonNodeProxyFactory.CloseableGatewayWithAttachments;
+import org.knime.python3.nodes.DelegatingNodeModel.ViewData.BackendViewData;
 import org.knime.python3.nodes.callback.AuthCallbackUtils;
 import org.knime.python3.nodes.extension.ExtensionNode;
 import org.knime.python3.nodes.ports.PythonPortObjects.PurePythonTablePortObject;
@@ -117,6 +118,7 @@
 import org.knime.python3.nodes.proxy.PythonNodeModelProxy.ExpiryDate;
 import org.knime.python3.nodes.proxy.PythonNodeModelProxy.FileStoreBasedFile;
 import org.knime.python3.nodes.proxy.PythonNodeProxy;
+import org.knime.python3.nodes.proxy.PythonNodeViewProxy.PythonDataServiceProxy.PythonViewData;
 import org.knime.python3.nodes.proxy.model.NodeConfigurationProxy;
 import org.knime.python3.nodes.proxy.model.NodeExecutionProxy;
 import org.knime.python3.nodes.settings.JsonNodeSettings;
@@ -368,7 +370,7 @@ private void initTableManager() {
     public ExecutionResult execute(final PortObject[] inData, final PortType[] outputPortTypes,
         final ExecutionContext exec, final FlowVariablesProxy flowVariablesProxy,
         final CredentialsProviderProxy credentialsProviderProxy, final WorkflowPropertiesProxy workflowPropertiesProxy,
-        final WarningConsumer warningConsumer) throws Exception {
+        final WarningConsumer warningConsumer, final BackendViewData viewData) throws Exception {
         initTableManager();
         Map<String, FileStore> fileStoresByKey = new HashMap<>();
         final var executionResult = new PythonExecutionResult();
@@ -551,8 +553,8 @@ public PythonToolResult execute_tool(final PurePythonTablePortObject toolTable,
             }
 
             @Override
-            public String get_internal_view_data() {
-                return ((DelegatingNodeModel)getNode().getNodeModel()).getInternalViewData();
+            public PythonViewData get_view_data() {
+                return toPythonViewData(viewData, fileStoresByKey, exec);
             }
 
         };
@@ -924,7 +926,7 @@ private void throwIfFailure() throws InvalidSettingsException {
 
     @Override
     public DataServiceProxy getDataServiceProxy(final JsonNodeSettings settings, final PortObject[] portObjects,
-        final String internalViewData, final PortMapProvider portMapProvider,
+        final BackendViewData viewData, final PortMapProvider portMapProvider,
         final CredentialsProviderProxy credentialsProvider) {
 
         loadValidatedSettings(settings);
@@ -938,9 +940,11 @@ public DataServiceProxy getDataServiceProxy(final JsonNodeSettings settings, fin
         var fileStoreSwitcher = FileStoreSwitcher.create(nnc);
         var exec = fileStoreSwitcher.createExecutionContext();
         var toolExecutor = new ToolExecutor(exec, nnc, m_tableManager);
-        var context = new DefaultViewContext(toolExecutor, portMapProvider, credentialsProvider, internalViewData);
 
         var fileStoresByKey = new HashMap<String, FileStore>();
+        var context = new DefaultViewContext(toolExecutor, portMapProvider, credentialsProvider,
+            toPythonViewData(viewData, fileStoresByKey, exec));
+
         final var knimeToPythonConversionContext =
             new PortObjectConversionContext(fileStoresByKey, m_tableManager, exec);
         var pythonPortObjects =
@@ -954,6 +958,17 @@ public String handleJsonRpcRequest(final String request) {
                 return pythonDataService.handleJsonRpcRequest(request);
             }
 
+            @Override
+            public BackendViewData getViewData() {
+                var viewData = pythonDataService.getViewData();
+                var conversionContext = new PortObjectConversionContext(fileStoresByKey, m_tableManager, exec);
+                var ports = viewData.ports();
+                var portObjects = viewData.ports().stream() //
+                    .map(po -> PythonPortTypeRegistry.convertPortObjectFromPython(po, conversionContext))//
+                    .toArray(PortObject[]::new);
+                return new BackendViewData(viewData.data(), portObjects);
+            }
+
             @Override
             public void close() throws Exception {
                 toolExecutor.close();
@@ -991,4 +1006,31 @@ public void close() {
         }
     }
 
+    private PythonViewData toPythonViewData(final BackendViewData viewData,
+        final Map<String, FileStore> fileStoresByKey, final ExecutionContext exec) {
+        if (viewData == null) {
+            return null;
+        }
+        var data = viewData.data();
+        var ports = viewData.ports();
+        var conversionContext = new PortObjectConversionContext(fileStoresByKey, m_tableManager, exec);
+        var pyPorts = Stream.of(ports)//
+            .map(po -> PythonPortTypeRegistry.convertPortObjectToPython(po, conversionContext))//
+            .toList();
+
+        return new PythonViewData() {
+
+            @Override
+            public String data() {
+                return data;
+            }
+
+            @Override
+            public List<PythonPortObject> ports() {
+                return pyPorts;
+            }
+
+        };
+    }
+
 }

org.knime.python3.nodes/src/main/java/org/knime/python3/nodes/DefaultViewContext.java

@@ -52,9 +52,11 @@
 import java.util.Map;
 
 import org.knime.core.node.workflow.ICredentials;
+import org.knime.python3.nodes.DelegatingNodeModel.ViewData.BackendViewData;
 import org.knime.python3.nodes.ports.PythonPortObjects.PurePythonTablePortObject;
 import org.knime.python3.nodes.ports.PythonPortObjects.PythonPortObject;
 import org.knime.python3.nodes.proxy.PythonNodeViewProxy;
+import org.knime.python3.nodes.proxy.PythonNodeViewProxy.PythonDataServiceProxy.PythonViewData;
 import org.knime.python3.nodes.proxy.model.NodeModelProxy.CredentialsProviderProxy;
 import org.knime.python3.nodes.proxy.model.NodeModelProxy.PortMapProvider;
 
@@ -73,14 +75,14 @@ final class DefaultViewContext implements PythonNodeViewProxy.PythonViewContext
 
     private final CredentialsProviderProxy m_credentialsProvider;
 
-    private final String m_internalViewData;
+    private final PythonViewData m_viewData;
 
     DefaultViewContext(final ToolExecutor toolExecutor, final PortMapProvider portMapProvider,
-        final CredentialsProviderProxy credentialsProvider, final String internalViewData) {
+        final CredentialsProviderProxy credentialsProvider, final PythonViewData viewData) {
         m_toolExecutor = toolExecutor;
         m_portMapProvider = portMapProvider;
         m_credentialsProvider = credentialsProvider;
-        m_internalViewData = internalViewData;
+        m_viewData = viewData;
     }
 
     @Override
@@ -112,7 +114,7 @@ public PythonToolResult execute_tool(final PurePythonTablePortObject toolTable,
     }
 
     @Override
-    public String get_internal_view_data() {
-        return m_internalViewData;
+    public PythonViewData get_view_data() {
+        return m_viewData;
     }
 }