Perf improvement: use a model that batch calls to RefreshObjects in t…

…he view, use FastObjectListView

Nats.Services.KeyValueStoreDemo/StoreClient/ProductInfo.cs

@@ -4,16 +4,25 @@
 
 namespace StoreClient
 {
-    public class ProductInfo
+    public class ProductInfo : StoreRowItem<Product>
     {
         public Product Product { get; private set; }
+        public ProductInfo()
+        {
+
+        }
         public ProductInfo(Product product)
         {
             Product = product;
             LastUpdate = DateTime.Now;
         }
         public void Update(Product product)
         {
+            if( Product == null)
+            {
+                Product = product;
+                return;
+            }
             Product.Price = product.Price;
             Product.Quantity= product.Quantity;
             LastUpdate = DateTime.Now;

Nats.Services.KeyValueStoreDemo/StoreClient/StoreClient.csproj

@@ -69,6 +69,8 @@
     </Compile>
     <Compile Include="Program.cs" />
     <Compile Include="Properties\AssemblyInfo.cs" />
+    <Compile Include="StoreClientModel.cs" />
+    <Compile Include="StoreRowItem.cs" />
     <EmbeddedResource Include="Properties\Resources.resx">
       <Generator>ResXFileCodeGenerator</Generator>
       <LastGenOutput>Resources.Designer.cs</LastGenOutput>

Nats.Services.KeyValueStoreDemo/StoreClient/StoreClientForm.cs

@@ -1,12 +1,9 @@
-using BrightIdeasSoftware;
-using Nats.Services.Core;
+using Nats.Services.Core;
 using Nats.Services.Core.DiscoveryService;
 using NATS.Client;
 using NLog;
 using StoreServices;
 using System;
-using System.Collections.Generic;
-using System.Linq;
 using System.Reflection;
 using System.Threading;
 using System.Threading.Tasks;
@@ -20,12 +17,11 @@ public partial class StoreClientForm : Form
         IConnection connection;
         NatsServiceFactory serviceFactory;
         IProductStoreService storeService;
-        private List<ProductInfo> productInfos;
+        StoreClientModel<string, Product, ProductInfo> model = new StoreClientModel<string, Product, ProductInfo>();
 
         public StoreClientForm()
         {
             InitializeComponent();
-            Generator.GenerateColumns(objectListView1, typeof(ProductInfo));
         }
 
         private async void StoreClientForm_LoadAsync(object sender, EventArgs e)
@@ -39,36 +35,16 @@ private async void StoreClientForm_LoadAsync(object sender, EventArgs e)
             string serverName = await Task.Run(() => DiscoverServer(connection, logger));
             logger.Info($"Server found: {serverName}.");
             Text += serverName;
-            var products = await Task.Run(()=>InitServices(serverName));
-            logger.Info($"Store initialized: {products.Count}");
-            InitData(products);
+            await InitServicesAsync(serverName);
+            logger.Info($"Store initialized: {objectListView1.GetItemCount()}");
         }
 
-        private List<Product> InitServices(string serverName)
+        private async Task InitServicesAsync(string serverName)
         {
             serviceFactory = new NatsServiceFactory(connection, serverName);
             storeService = serviceFactory.BuildServiceClient<IProductStoreService>();
-            storeService.ValueUpdated += OnValueUpdated;
-            var products = storeService.GetAllValues();
-            return products;
-        }
-
-        private void OnValueUpdated(Product product)
-        {
-            if (productInfos == null) return; 
-            var productInfo = productInfos.FirstOrDefault(pI => pI.Name == product.Name);
-            if( productInfo != null)
-            {
-                productInfo.Update(product);
-                objectListView1.RefreshObject(productInfo);
-            }
-        }
-
-        private void InitData(List<Product> products)
-        {
-            Text += $", {products.Count} products";
-            var tmp  = products.Select(product => new ProductInfo(product)).ToList();
-            productInfos = tmp;
+            await model.InitAsync(storeService, objectListView1);
+            Text += $", {objectListView1.GetItemCount()} products";
         }
 
         public static string DiscoverServer(IConnection connection, ILogger logger=null, int periodMs=1000)

Nats.Services.KeyValueStoreDemo/StoreClient/StoreClientModel.cs

@@ -0,0 +1,89 @@
+using BrightIdeasSoftware;
+using Nats.Services.Core.KeyValueStoreService;
+using System;
+using System.Collections.Generic;
+using System.Diagnostics;
+using System.Linq;
+using System.Threading.Tasks;
+using System.Windows.Forms;
+
+namespace StoreClient
+{
+    public class StoreClientModel<T_Key, T_Value, T_RowItem> 
+        where T_Value : IKeyIdentifiable<T_Key>
+        where T_RowItem : class, StoreRowItem<T_Value>, new()
+    {
+        IKeyValueStoreService<T_Key, T_Value> service;
+
+        Dictionary<T_Key, T_RowItem> dicoKeyRows = new Dictionary<T_Key, T_RowItem>();
+        Dictionary<T_Key, T_RowItem> updatedRows = new Dictionary<T_Key, T_RowItem>();
+        Timer timer;
+        ObjectListView view;
+
+        public async Task InitAsync(IKeyValueStoreService<T_Key, T_Value> service, ObjectListView view)
+        {
+            this.service = service;
+            this.view = view;
+
+            var items= await Task.Run(() => service.GetAllValues());
+            foreach(var item in items)
+            {
+                var rowItem = new T_RowItem();
+                rowItem.Update(item);
+                dicoKeyRows[item.Key] = rowItem;
+            }
+            Generator.GenerateColumns(view, typeof(T_RowItem));
+
+            view.Objects = dicoKeyRows.Values;
+            timer = new Timer();
+            timer.Tick += UpdateBatch;
+            timer.Start();
+            service.ValueUpdated += OnValueUpdated;
+        }
+
+        private void UpdateBatch(object sender, EventArgs evt)
+        {
+            List<T_RowItem> values;
+            lock (updatedRows)
+            {
+                if(updatedRows.Count == 0)
+                {
+                    return;
+                }
+                values = updatedRows.Values.ToList();
+                updatedRows.Clear();
+            }
+            view.Invoke( (Action)(() => RefreshRows(values)));
+        }
+
+        Stopwatch sw = new Stopwatch();
+        long n = 0;
+        private void RefreshRows(List<T_RowItem> values)
+        {
+            n++;
+            sw.Start();
+            view.RefreshObjects(values);
+            sw.Stop();
+            if( n % 10 == 0)
+            {
+                Debug.WriteLine("n: " + n + ", t=" + sw.ElapsedMilliseconds + ", avg: " + (sw.ElapsedMilliseconds/ (double)n));
+            }
+        }
+
+        private void OnValueUpdated(T_Value obj)
+        {
+            lock(updatedRows)
+            {
+                T_RowItem rowItem; 
+                if(! dicoKeyRows.TryGetValue(obj.Key, out rowItem))
+                {
+                    rowItem = new T_RowItem();
+                    dicoKeyRows[obj.Key] = rowItem;
+                }
+
+                rowItem.Update(obj);
+                updatedRows[obj.Key] = rowItem;
+            }
+        }
+    }
+}

Nats.Services.KeyValueStoreDemo/StoreClient/StoreRowItem.cs

@@ -0,0 +1,7 @@
+namespace StoreClient
+{
+    public interface StoreRowItem<T_Value>
+    {
+        void Update(T_Value value);
+    }
+}