Improve Core.Data Serialization and Add Remember Node

src/Libraries/CoreNodeModels/Properties/Resources.en-US.resx

@@ -641,4 +641,13 @@ Default value: {0}</value>
   <data name="TooltipTextQuery" xml:space="preserve">
     <value>Nodes that query data</value>
   </data>
+  <data name="RememberDescription" xml:space="preserve">
+    <value>Store data passing through this node to the Dynamo file. Return the stored data if the input is null.</value>
+  </data>
+  <data name="RememberInputToolTip" xml:space="preserve">
+    <value>Data to sample and store in the file.</value>
+  </data>
+  <data name="RememberOuputToolTip" xml:space="preserve">
+    <value>Data</value>
+  </data>
 </root>

src/Libraries/CoreNodeModels/Properties/Resources.resx

@@ -641,4 +641,13 @@ Default value: {0}</value>
   <data name="TooltipTextQuery" xml:space="preserve">
     <value>Nodes that query data</value>
   </data>
+  <data name="RememberDescription" xml:space="preserve">
+    <value>Store data passing through this node to the Dynamo file. Return the stored data if the input is null.</value>
+  </data>
+  <data name="RememberInputToolTip" xml:space="preserve">
+    <value>Data to sample and store in the file.</value>
+  </data>
+  <data name="RememberOuputToolTip" xml:space="preserve">
+    <value>Data</value>
+  </data>
 </root>

src/Libraries/CoreNodeModels/Remember.cs

@@ -0,0 +1,148 @@
+using Dynamo.Graph;
+using Dynamo.Graph.Nodes;
+using Newtonsoft.Json;
+using ProtoCore.AST.AssociativeAST;
+using System;
+using System.Collections.Generic;
+using System.ComponentModel;
+using System.Linq;
+using System.Reflection;
+using System.Text;
+using System.Threading.Tasks;
+using VMDataBridge;
+
+namespace CoreNodeModels
+{
+    [NodeName("Remember")]
+    [NodeDescription(nameof(Properties.Resources.RememberDescription), typeof(Properties.Resources))]
+    [NodeCategory("Core.Data")]
+    [InPortNames(">")]
+    [InPortTypes("object")]
+    [InPortDescriptions(typeof(Properties.Resources), nameof(Properties.Resources.RememberInputToolTip))]
+    [OutPortNames(">")]
+    [OutPortTypes("object")]
+    [OutPortDescriptions(typeof(Properties.Resources), nameof(Properties.Resources.RememberOuputToolTip))]
+    [IsDesignScriptCompatible]
+    [DynamoServices.RegisterForTrace]
+    public class Remember : NodeModel
+    {
+        private bool _deactivateNode;
+        private string _cache = "";
+        private string _updatedToolTipText = "";
+
+        [JsonProperty("Cache")]
+        public string Cache
+        {
+            get { return _cache; }
+            set
+            {
+                var valueToSet = value == null ? "" : value;
+                if (valueToSet != _cache)
+                {
+                    _cache = valueToSet;
+                    MarkNodeAsModified();
+                }
+            }
+        }
+
+        [JsonConstructor]
+        private Remember(IEnumerable<PortModel> inPorts, IEnumerable<PortModel> outPorts) : base(inPorts, outPorts)
+        {
+            PropertyChanged += OnPropertyChanged;
+        }
+
+        public Remember()
+        {
+            RegisterAllPorts();
+            PropertyChanged += OnPropertyChanged;
+        }
+
+        private void OnPropertyChanged(object sender, PropertyChangedEventArgs e)
+        {
+            switch (e.PropertyName)
+            {
+                case "State":
+                    if (State == ElementState.Warning)
+                    {
+                        Cache = "";
+                    }
+                    break;
+
+                case "ToolTipText":
+                    if (State == ElementState.Warning && ToolTipText != _updatedToolTipText)
+                    {
+                        string[] errorMessages =
+                            ToolTipText.Split(new[] { "\r\n", "\n" }, StringSplitOptions.None);
+                        _updatedToolTipText = errorMessages.Last();
+                        ToolTipText = _updatedToolTipText;
+                    }
+
+                    break;
+
+                default:
+                    // Nothing to handle
+                    break;
+            }
+        }
+
+        protected override void OnBuilt()
+        {
+            base.OnBuilt();
+            DataBridge.Instance.RegisterCallback(GUID.ToString(), DataBridgeCallback);
+        }
+
+        public override void Dispose()
+        {
+            base.Dispose();
+            DataBridge.Instance.UnregisterCallback(GUID.ToString());
+        }
+
+        private static readonly string BuiltinDictionaryTypeName = typeof(DesignScript.Builtin.Dictionary).FullName;
+        private static readonly string BuiltinDictionaryGet = nameof(DesignScript.Builtin.Dictionary.ValueAtKey);
+
+        public override IEnumerable<AssociativeNode> BuildOutputAst(List<AssociativeNode> inputAstNodes)
+        {
+            // Check that node can run
+            if (_deactivateNode)
+            {
+                return new[] { AstFactory.BuildAssignment(GetAstIdentifierForOutputIndex(0), AstFactory.BuildNullNode()) };
+            }
+
+            var resultAst = new List<AssociativeNode>();
+
+            var funtionInputs = new List<AssociativeNode> { inputAstNodes[0], AstFactory.BuildStringNode(Cache) };
+
+            //First build the function call
+            var functionCall = AstFactory.BuildFunctionCall(
+               new Func<object, string, Dictionary<string, object>>(DSCore.Data.Remember), funtionInputs);
+
+            var functionCallIndent = AstFactory.BuildIdentifier(GUID + "_func");
+
+            resultAst.Add(AstFactory.BuildAssignment(functionCallIndent, functionCall));
+
+            //Next add the first key value pair to the output port
+            var getFirstKey = AstFactory.BuildFunctionCall(BuiltinDictionaryTypeName, BuiltinDictionaryGet,
+                new List<AssociativeNode> { functionCallIndent, AstFactory.BuildStringNode(">") });
+
+            resultAst.Add(AstFactory.BuildAssignment(GetAstIdentifierForOutputIndex(0), getFirstKey));
+
+            //Second get the key value pair to pass to the databridge callback
+            var getSecondKey = AstFactory.BuildFunctionCall(BuiltinDictionaryTypeName, BuiltinDictionaryGet,
+                new List<AssociativeNode> { functionCallIndent, AstFactory.BuildStringNode("Cache") });
+
+            resultAst.Add(AstFactory.BuildAssignment(
+                    AstFactory.BuildIdentifier(GUID + "_db"),
+                    DataBridge.GenerateBridgeDataAst(GUID.ToString(), getSecondKey)));
+
+            return resultAst;
+        }
+
+        private void DataBridgeCallback(object callbackObject)
+        {
+            if (DSCore.Data.CanObjectBeCached(callbackObject))
+            {
+                Cache = callbackObject as String;
+            }
+        }
+    }
+}

src/Libraries/CoreNodes/CoreNodes.csproj

@@ -44,6 +44,11 @@
       <Project>{c0d6dee5-5532-4345-9c66-4c00d7fdb8be}</Project>
       <Name>DesignScriptBuiltin</Name>
     </ProjectReference>
+    <ProjectReference Include="..\DynamoUnits\UnitsCore.csproj">
+      <Project>{6e0a079e-85f1-45a1-ad5b-9855e4344809}</Project>
+      <Name>Units</Name>
+      <Private>False</Private>
+    </ProjectReference>
   </ItemGroup>
   <ItemGroup>
     <Content Include="DSCoreNodes.Migrations.xml">