Merge pull request #1 from Kritner/grainReuse

Grain reuse/Stateful grains

src/Kritner.OrleansGettingStarted.Client/Program.cs

@@ -25,6 +25,7 @@ private static async Task<int> RunMainAsync()
                 using (var client = await StartClientWithRetries())
                 {
                     await DoClientWork(client);
+                    await DoStatefulWork(client);
                     Console.ReadKey();
                 }
 
@@ -78,19 +79,59 @@ private static async Task<bool> RetryFilter(Exception exception)
 
         private static async Task DoClientWork(IClusterClient client)
         {
-            Console.WriteLine("Hello, what should I call you?");
-            var name = Console.ReadLine();
+            // example of calling grains from the initialized client
+            var grain = client.GetGrain<IHelloWorld>(Guid.NewGuid());
+            var grain2 = client.GetGrain<IHelloWorld>(Guid.NewGuid());
+
+            Console.WriteLine($"{await grain.SayHello("1")}");
+            Console.WriteLine($"{await grain2.SayHello("2")}");
+            Console.WriteLine($"{await grain.SayHello("3")}");
+
+            PrintSeparatorThing();
+        }
+
+        private static async Task DoStatefulWork(IClusterClient client)
+        {
+            var kritnerGrain = client.GetGrain<IVisitTracker>("[email protected]");
+            var notKritnerGrain = client.GetGrain<IVisitTracker>("[email protected]");
+
+            await PrettyPrintGrainVisits(kritnerGrain);
+            await PrettyPrintGrainVisits(notKritnerGrain);
+
+            PrintSeparatorThing();
+            Console.WriteLine("Ayyy some people are visiting!");
+
+            await kritnerGrain.Visit();
+            await kritnerGrain.Visit();
+            await notKritnerGrain.Visit();
+
+            PrintSeparatorThing();
 
-            if (string.IsNullOrEmpty(name))
+            await PrettyPrintGrainVisits(kritnerGrain);
+            await PrettyPrintGrainVisits(notKritnerGrain);
+
+            PrintSeparatorThing();
+            Console.Write("ayyy kritner's visiting even more!");
+
+            for (int i = 0; i < 5; i++)
             {
-                name = "anon";
+                await kritnerGrain.Visit();
             }
 
-            // example of calling grains from the initialized client
-            var grain = client.GetGrain<IHelloWorld>(Guid.NewGuid());
-
-            var response = await grain.SayHello(name);
-            Console.WriteLine($"\n\n{response}\n\n");
+            PrintSeparatorThing();
+
+            await PrettyPrintGrainVisits(kritnerGrain);
+            await PrettyPrintGrainVisits(notKritnerGrain);
+        }
+
+        private static async Task PrettyPrintGrainVisits(IVisitTracker grain)
+        {
+            Console.WriteLine($"{grain.GetPrimaryKeyString()} has visited {await grain.GetNumberOfVisits()} times");
+        }
+
+        private static void PrintSeparatorThing()
+        {
+            Console.WriteLine($"{Environment.NewLine}-----{Environment.NewLine}");
         }
     }
 }

src/Kritner.OrleansGettingStarted.GrainInterfaces/IVisitTracker.cs

@@ -0,0 +1,11 @@
+using Orleans;
+using System.Threading.Tasks;
+
+namespace Kritner.OrleansGettingStarted.GrainInterfaces
+{
+    public interface IVisitTracker : IGrainWithStringKey
+    {
+        Task<int> GetNumberOfVisits();
+        Task Visit();
+    }
+}

src/Kritner.OrleansGettingStarted.Grains/Constants.cs

@@ -0,0 +1,11 @@
+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace Kritner.OrleansGettingStarted.Grains
+{
+    public class Constants
+    {
+        public const string OrleansMemoryProvider = "OrleansMemoryProvider";
+    }
+}

src/Kritner.OrleansGettingStarted.Grains/HelloWorld.cs

@@ -8,7 +8,7 @@ public class HelloWorld : Grain, IHelloWorld
     {
         public Task<string> SayHello(string name)
         {
-            return Task.FromResult($"Hello World! Orleans is neato torpedo, eh {name}?");
+            return Task.FromResult($"Hello from grain {this.GetGrainIdentity()}, {name}!");
         }
     }
 }

src/Kritner.OrleansGettingStarted.Grains/VisitTracker.cs

@@ -0,0 +1,39 @@
+using Kritner.OrleansGettingStarted.GrainInterfaces;
+using Orleans;
+using Orleans.Providers;
+using System;
+using System.Threading.Tasks;
+
+namespace Kritner.OrleansGettingStarted.Grains
+{
+    [StorageProvider(ProviderName = Constants.OrleansMemoryProvider)]
+    public class VisitTracker : Grain<VisitTrackerState>, IVisitTracker
+    {
+        public Task<int> GetNumberOfVisits()
+        {
+            return Task.FromResult(State.NumberOfVisits);
+        }
+
+        public async Task Visit()
+        {
+            var now = DateTime.Now;
+
+            if (!State.FirstVisit.HasValue)
+            {
+                State.FirstVisit = now;
+            }
+
+            State.NumberOfVisits++;
+            State.LastVisit = now;
+
+            await WriteStateAsync();
+        }
+    }
+
+    public class VisitTrackerState
+    {
+        public DateTime? FirstVisit { get; set; }
+        public DateTime? LastVisit { get; set; }
+        public int NumberOfVisits { get; set; }
+    }
+}

src/Kritner.OrleansGettingStarted.SiloHost/Program.cs

@@ -46,6 +46,7 @@ private static async Task<ISiloHost> StartSilo()
                     options.ServiceId = "HelloWorldApp";
                 })
                 .Configure<EndpointOptions>(options => options.AdvertisedIPAddress = IPAddress.Loopback)
+                .AddMemoryGrainStorage(Constants.OrleansMemoryProvider)
                 //.ConfigureApplicationParts(parts => parts.AddApplicationPart(typeof(HelloWorld).Assembly).WithReferences())
                 .ConfigureLogging(logging => logging.AddConsole());