Introduce SimulationSnapshot

modules/client-simulation/src/Volo.ClientSimulation.Web/Pages/ClientSimulation/SimulationArea.cshtml

@@ -8,18 +8,18 @@
 @model Volo.ClientSimulation.Pages.ClientSimulation.SimulationAreaModel
 <abp-alert alert-type="Primary">
     <form class="d-inline" id="StartButtonForm" method="post" asp-page-handler="Start" data-ajaxForm="true">
-        <abp-button button-type="Primary" type="submit" disabled="@(Model.Simulation.State != SimulationState.Stopped)">Start</abp-button>
+        <abp-button button-type="Primary" type="submit" disabled="@(Model.Snapshot.State != SimulationState.Stopped)">Start</abp-button>
     </form>
     <form class="d-inline" id="StopButtonForm" method="post" asp-page-handler="Stop" data-ajaxForm="true">
-        <abp-button button-type="Primary" type="submit" disabled="@(Model.Simulation.State != SimulationState.Started)">Stop</abp-button>
+        <abp-button button-type="Primary" type="submit" disabled="@(Model.Snapshot.State != SimulationState.Started)">Stop</abp-button>
     </form>
     <span class="ml-3">
-        @Model.Simulation.State
+        @Model.Snapshot.State
     </span>
 </abp-alert>
 <abp-card class="mt-3">
     <abp-card-body>
-        @foreach (var client in Model.Simulation.Clients)
+        @foreach (var client in Model.Snapshot.Clients)
         {
             <span class="simulation-client simulation-client-@client.State.ToString().ToLowerInvariant()">
                 <span class="simulation-client-icon">
@@ -37,12 +37,12 @@
                     }
                 </span>
                 <span class="simulation-client-scenario">
-                    @client.Scenario.GetDisplayText()
+                    @client.Scenario.DisplayText
                 </span>
                 <span class="simulation-client-scenario-current-step">
                 @if (client.State != ClientState.Stopped)
                 {
-                    <text>| @client.Scenario.CurrentStep.GetDisplayText()</text>
+                    <text>| @client.Scenario.CurrentStep.DisplayText</text>
                 }
                 </span>
             </span>

modules/client-simulation/src/Volo.ClientSimulation.Web/Pages/ClientSimulation/SimulationArea.cshtml.cs

@@ -1,12 +1,15 @@
 using System.Threading.Tasks;
 using Microsoft.AspNetCore.Mvc;
 using Microsoft.AspNetCore.Mvc.RazorPages;
+using Volo.ClientSimulation.Snapshot;
 
 namespace Volo.ClientSimulation.Pages.ClientSimulation
 {
     public class SimulationAreaModel : PageModel
     {
-        public Simulation Simulation { get; }
+        public SimulationSnapshot Snapshot { get; private set; }
+
+        protected Simulation Simulation { get; }
 
         public SimulationAreaModel(Simulation simulation)
         {
@@ -15,6 +18,7 @@ namespace Volo.ClientSimulation.Pages.ClientSimulation
 
         public Task OnGetAsync()
         {
+            Snapshot = Simulation.CreateSnapshot();
             return Task.CompletedTask;
         }
 

modules/client-simulation/src/Volo.ClientSimulation/Volo/ClientSimulation/Clients/Client.cs

@@ -1,13 +1,17 @@
-using System.Threading;
+using System;
+using System.Threading;
 using Volo.Abp;
 using Volo.Abp.DependencyInjection;
 using Volo.Abp.Threading;
 using Volo.ClientSimulation.Scenarios;
+using Volo.ClientSimulation.Snapshot;
 
 namespace Volo.ClientSimulation.Clients
 {
     public class Client : IClient, ITransientDependency
     {
+        public event EventHandler Stopped;
+
         public Scenario Scenario { get; private set; }
 
         public ClientState State
@@ -23,7 +27,15 @@ namespace Volo.ClientSimulation.Clients
 
         public void Initialize(Scenario scenario)
         {
-            Scenario = scenario;
+            lock (SyncLock)
+            {
+                if (State != ClientState.Stopped)
+                {
+                    throw new UserFriendlyException($"Client should be stopped to be able to initialize it. Current state is '{State}'.");
+                }
+
+                Scenario = scenario;
+            }
         }
 
         public void Start()
@@ -37,6 +49,7 @@ namespace Volo.ClientSimulation.Clients
 
                 State = ClientState.Running;
 
+                Scenario.Reset();
                 _thread = new Thread(Run);
                 _thread.Start();
             }
@@ -55,10 +68,20 @@ namespace Volo.ClientSimulation.Clients
             }
         }
 
-        private void Run()
+        public ClientSnapshot CreateSnapshot()
         {
-            Scenario.Reset();
+            lock (SyncLock)
+            {
+                return new ClientSnapshot
+                {
+                    State = State,
+                    Scenario = Scenario.CreateSnapshot()
+                };
+            }
+        }
 
+        private void Run()
+        {
             while (true)
             {
                 lock (SyncLock)
@@ -66,6 +89,8 @@ namespace Volo.ClientSimulation.Clients
                     if (State != ClientState.Running)
                     {
                         State = ClientState.Stopped;
+                        _thread = null;
+                        Stopped.InvokeSafely(this);
                         break;
                     }
                 }

modules/client-simulation/src/Volo.ClientSimulation/Volo/ClientSimulation/Clients/IClient.cs

@@ -1,9 +1,13 @@
-using Volo.ClientSimulation.Scenarios;
+using System;
+using Volo.ClientSimulation.Scenarios;
+using Volo.ClientSimulation.Snapshot;
 
 namespace Volo.ClientSimulation.Clients
 {
     public interface IClient
     {
+        event EventHandler Stopped;
+
         Scenario Scenario { get; }
 
         ClientState State { get; }
@@ -13,5 +17,7 @@ namespace Volo.ClientSimulation.Clients
         void Start();
 
         void Stop();
+
+        ClientSnapshot CreateSnapshot();
     }
 }

modules/client-simulation/src/Volo.ClientSimulation/Volo/ClientSimulation/Scenarios/Scenario.cs

@@ -1,29 +1,30 @@
 using System;
 using System.Collections.Generic;
-using System.Collections.Immutable;
+using System.Linq;
 using System.Threading.Tasks;
 using Volo.Abp.DependencyInjection;
+using Volo.ClientSimulation.Snapshot;
 
 namespace Volo.ClientSimulation.Scenarios
 {
     public abstract class Scenario : ITransientDependency
     {
-        public IReadOnlyList<ScenarioStep> Steps => StepList.ToImmutableList();
-        protected List<ScenarioStep> StepList { get; }
+        protected List<ScenarioStep> Steps { get; }
 
-        public ScenarioStep CurrentStep
+        protected ScenarioStep CurrentStep
         {
             get
             {
                 CheckStepCount();
-                return StepList[CurrentStepIndex];
+                return Steps[CurrentStepIndex];
             }
         }
-        public int CurrentStepIndex { get; protected set; }
+
+        protected int CurrentStepIndex { get; set; }
 
         protected Scenario()
         {
-            StepList = new List<ScenarioStep>();
+            Steps = new List<ScenarioStep>();
         }
 
         public virtual string GetDisplayText()
@@ -37,11 +38,11 @@ namespace Volo.ClientSimulation.Scenarios
         {
             CheckStepCount();
 
-            await StepList[CurrentStepIndex].RunAsync();
+            await Steps[CurrentStepIndex].RunAsync();
 
             CurrentStepIndex++;
 
-            if (CurrentStepIndex >= StepList.Count)
+            if (CurrentStepIndex >= Steps.Count)
             {
                 CurrentStepIndex = 0;
             }
@@ -52,19 +53,29 @@ namespace Volo.ClientSimulation.Scenarios
             CurrentStepIndex = 0;
         }
 
+        public ScenarioSnapshot CreateSnapshot()
+        {
+            return new ScenarioSnapshot
+            {
+                DisplayText = GetDisplayText(),
+                Steps = Steps.Select(s => s.CreateSnapshot()).ToList(),
+                CurrentStep = CurrentStep.CreateSnapshot()
+            };
+        }
+
+        protected void AddStep(ScenarioStep step)
+        {
+            Steps.Add(step);
+        }
+
         private void CheckStepCount()
         {
-            if (StepList.Count <= 0)
+            if (Steps.Count <= 0)
             {
                 throw new ApplicationException(
                     $"No Steps added to the scenario '{GetDisplayText()}'"
                 );
             }
         }
-
-        protected void AddStep(ScenarioStep step)
-        {
-            StepList.Add(step);
-        }
     }
 }

modules/client-simulation/src/Volo.ClientSimulation/Volo/ClientSimulation/Scenarios/ScenarioStep.cs

@@ -1,6 +1,7 @@
 using System;
 using System.Diagnostics;
 using System.Threading.Tasks;
+using Volo.ClientSimulation.Snapshot;
 
 namespace Volo.ClientSimulation.Scenarios
 {
@@ -46,5 +47,13 @@ namespace Volo.ClientSimulation.Scenarios
                 .Name
                 .RemovePostFix(nameof(ScenarioStep));
         }
+
+        public ScenarioStepSnapshot CreateSnapshot()
+        {
+            return new ScenarioStepSnapshot
+            {
+                DisplayText = GetDisplayText()
+            };
+        }
     }
 }

modules/client-simulation/src/Volo.ClientSimulation/Volo/ClientSimulation/Simulation.cs

@@ -1,23 +1,29 @@
 using System;
 using System.Collections.Generic;
+using System.Linq;
 using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.Logging;
+using Microsoft.Extensions.Logging.Abstractions;
 using Microsoft.Extensions.Options;
 using Volo.Abp;
 using Volo.Abp.DependencyInjection;
 using Volo.ClientSimulation.Clients;
 using Volo.ClientSimulation.Scenarios;
+using Volo.ClientSimulation.Snapshot;
 
 namespace Volo.ClientSimulation
 {
     public class Simulation : ISingletonDependency, IDisposable
     {
+        public ILogger<Simulation> Logger { get; set; }
+
         public SimulationState State { get; private set; }
 
         public List<IClient> Clients { get; }
 
         protected ClientSimulationOptions Options { get; }
-
-        protected IServiceScope ServiceScope { get; }
+        protected IServiceScopeFactory ServiceScopeFactory { get; }
+        protected IServiceScope ServiceScope { get; private set; }
 
         protected readonly object SyncObj = new object();
 
@@ -25,27 +31,15 @@ namespace Volo.ClientSimulation
             IServiceScopeFactory serviceScopeFactory,
             IOptions<ClientSimulationOptions> options)
         {
+            ServiceScopeFactory = serviceScopeFactory;
             Options = options.Value;
-            ServiceScope = serviceScopeFactory.CreateScope();
 
-            Clients = new List<IClient>();
+            Logger = NullLogger<Simulation>.Instance;
 
-            foreach (var scenarioConfiguration in Options.Scenarios)
-            {
-                for (int i = 0; i < scenarioConfiguration.ClientCount; i++)
-                {
-                    var scenario = (Scenario) ServiceScope.ServiceProvider.GetRequiredService(
-                        scenarioConfiguration.ScenarioType
-                    );
-
-                    var client = ServiceScope.ServiceProvider.GetRequiredService<IClient>();
-                    client.Initialize(scenario);
-                    Clients.Add(client);
-                }
-            }
+            Clients = new List<IClient>();
         }
 
-        public void Start()
+        public virtual void Start()
         {
             lock (SyncObj)
             {
@@ -56,16 +50,42 @@ namespace Volo.ClientSimulation
 
                 State = SimulationState.Starting;
 
-                foreach (var client in Clients)
+                try
                 {
-                    client.Start();
+                    DisposeResources();
+                    ServiceScope = ServiceScopeFactory.CreateScope();
+
+                    foreach (var scenarioConfiguration in Options.Scenarios)
+                    {
+                        for (int i = 0; i < scenarioConfiguration.ClientCount; i++)
+                        {
+                            var scenario = (Scenario)ServiceScope.ServiceProvider.GetRequiredService(
+                                scenarioConfiguration.ScenarioType
+                            );
+
+                            var client = ServiceScope.ServiceProvider.GetRequiredService<IClient>();
+                            client.Stopped += Client_OnStopped;
+                            client.Initialize(scenario);
+                            Clients.Add(client);
+                        }
+                    }
+
+                    foreach (var client in Clients)
+                    {
+                        client.Start();
+                    }
+
+                    State = SimulationState.Started;
+                }
+                catch(Exception ex)
+                {
+                    Logger.LogException(ex);
+                    State = SimulationState.Stopped;
                 }
-
-                State = SimulationState.Started;
             }
         }
 
-        public void Stop()
+        public virtual void Stop()
         {
             lock (SyncObj)
             {
@@ -80,14 +100,48 @@ namespace Volo.ClientSimulation
                 {
                     client.Stop();
                 }
+            }
+        }
 
-                State = SimulationState.Stopped;
+        public virtual SimulationSnapshot CreateSnapshot()
+        {
+            lock (SyncObj)
+            {
+                return new SimulationSnapshot
+                {
+                    State = State,
+                    Clients = Clients
+                        .Select(c => c.CreateSnapshot())
+                        .ToList()
+                };
+            }
+        }
+
+        public virtual void Dispose()
+        {
+            DisposeResources();
+        }
+
+        protected virtual void Client_OnStopped(object sender, EventArgs e)
+        {
+            lock (SyncObj)
+            {
+                if (Clients.All(c => c.State == ClientState.Stopped))
+                {
+                    OnStopped();
+                }
             }
         }
 
-        public void Dispose()
+        private void OnStopped()
+        {
+            State = SimulationState.Stopped;
+        }
+
+        private void DisposeResources()
         {
-            ServiceScope.Dispose();
+            Clients.Clear();
+            ServiceScope?.Dispose();
         }
     }
 }

modules/client-simulation/src/Volo.ClientSimulation/Volo/ClientSimulation/Snapshot/ClientSnapshot.cs

@@ -0,0 +1,13 @@
+using System;
+using Volo.ClientSimulation.Clients;
+
+namespace Volo.ClientSimulation.Snapshot
+{
+    [Serializable]
+    public class ClientSnapshot
+    {
+        public ClientState State { get; set; }
+
+        public ScenarioSnapshot Scenario { get; set; }
+    }
+}

modules/client-simulation/src/Volo.ClientSimulation/Volo/ClientSimulation/Snapshot/ScenarioSnapshot.cs

@@ -0,0 +1,15 @@
+using System;
+using System.Collections.Generic;
+
+namespace Volo.ClientSimulation.Snapshot
+{
+    [Serializable]
+    public class ScenarioSnapshot
+    {
+        public string DisplayText { get; set; }
+
+        public List<ScenarioStepSnapshot> Steps { get; set; }
+
+        public ScenarioStepSnapshot CurrentStep { get; set; }
+    }
+}

modules/client-simulation/src/Volo.ClientSimulation/Volo/ClientSimulation/Snapshot/ScenarioStepSnapshot.cs

@@ -0,0 +1,10 @@
+using System;
+
+namespace Volo.ClientSimulation.Snapshot
+{
+    [Serializable]
+    public class ScenarioStepSnapshot
+    {
+        public string DisplayText { get; set; }
+    }
+}

modules/client-simulation/src/Volo.ClientSimulation/Volo/ClientSimulation/Snapshot/SimulationSnapshot.cs

@@ -0,0 +1,13 @@
+using System;
+using System.Collections.Generic;
+
+namespace Volo.ClientSimulation.Snapshot
+{
+    [Serializable]
+    public class SimulationSnapshot
+    {
+        public SimulationState State { get; set; }
+
+        public List<ClientSnapshot> Clients { get; set; }
+    }
+}