Mitigate race condition, introduce timeout and simplify code for property gets

Author: softworkz

src/ElectronNET.API/API/ApiBase.cs

@@ -1,14 +1,20 @@
 namespace ElectronNET.API
 {
+    using System;
     using System.Collections.Concurrent;
+    using System.Diagnostics;
     using System.Runtime.CompilerServices;
+    using System.Threading.Tasks;
     using ElectronNET.Common;
 
     public abstract class ApiBase
     {
         internal const int PropertyTimeout = 1000;
 
         private readonly string objectName;
+        private readonly ConcurrentDictionary<string, PropertyGetter> propertyGetters = new ConcurrentDictionary<string, PropertyGetter>();
+        private readonly ConcurrentDictionary<string, string> propertyEventNames = new ConcurrentDictionary<string, string>();
+        private readonly ConcurrentDictionary<string, string> propertyMessageNames = new ConcurrentDictionary<string, string>();
         private readonly ConcurrentDictionary<string, string> methodMessageNames = new ConcurrentDictionary<string, string>();
 
         public virtual int Id
@@ -82,5 +88,77 @@ protected void CallMethod3(object val1, object val2, object val3, [CallerMemberN
                 BridgeConnector.Socket.Emit(messageName, val1, val2, val3);
             }
         }
+
+        protected Task<T> GetPropertyAsync<T>([CallerMemberName] string callerName = null)
+        {
+            Debug.Assert(callerName != null, nameof(callerName) + " != null");
+
+            return this.propertyGetters.GetOrAdd(callerName, _ =>
+            {
+                var getter = new PropertyGetter<T>(this, callerName, PropertyTimeout);
+
+                getter.Task<T>().ContinueWith(_ => this.propertyGetters.TryRemove(callerName, out var _));
+
+                return getter;
+            }).Task<T>();
+        }
+
+        internal abstract class PropertyGetter
+        {
+            public abstract Task<T> Task<T>();
+        }
+
+        internal class PropertyGetter<T> : PropertyGetter
+        {
+            private readonly Task<T> tcsTask;
+            private TaskCompletionSource<T> tcs;
+
+            public PropertyGetter(ApiBase apiBase, string callerName, int timeoutMs)
+            {
+                this.tcs = new TaskCompletionSource<T>(TaskCreationOptions.RunContinuationsAsynchronously);
+                this.tcsTask = this.tcs.Task;
+
+                var eventName = apiBase.propertyEventNames.GetOrAdd(callerName, s => $"{apiBase.objectName}-{s.StripAsync().LowerFirst()}{apiBase.SocketEventCompleteSuffix}");
+                var messageName = apiBase.propertyMessageNames.GetOrAdd(callerName, s => apiBase.objectName + s.StripAsync());
+
+                BridgeConnector.Socket.On<T>(eventName, (result) =>
+                {
+                    BridgeConnector.Socket.Off(eventName);
+
+                    lock (this)
+                    {
+                        this.tcs?.SetResult(result);
+                        this.tcs = null;
+                    }
+                });
+
+                if (apiBase.Id >= 0)
+                {
+                    BridgeConnector.Socket.Emit(messageName, apiBase.Id);
+                }
+                else
+                {
+                    BridgeConnector.Socket.Emit(messageName);
+                }
+
+                System.Threading.Tasks.Task.Delay(ApiBase.PropertyTimeout).ContinueWith(_ =>
+                {
+                    if (this.tcs != null)
+                    {
+                        lock (this)
+                        {
+                            var ex = new TimeoutException($"No response after {timeoutMs:D}ms trying to retrieve value {apiBase.objectName}.{callerName}()");
+                            this.tcs.TrySetException(ex);
+                            this.tcs = null;
+                        }
+                    }
+                });
+            }
+
+            public override Task<T1> Task<T1>()
+            {
+                return this.tcsTask as Task<T1>;
+            }
+        }
     }
 }

src/ElectronNET.API/API/App.cs

@@ -374,20 +374,7 @@ public Task<string> NameAsync
         {
             get
             {
-                return Task.Run<string>(() =>
-                {
-                    var taskCompletionSource = new TaskCompletionSource<string>();
-
-                    BridgeConnector.Socket.On("appGetNameCompleted", (result) =>
-                    {
-                        BridgeConnector.Socket.Off("appGetNameCompleted");
-                        taskCompletionSource.SetResult((string)result);
-                    });
-
-                    BridgeConnector.Socket.Emit("appGetName");
-
-                    return taskCompletionSource.Task;
-                });
+                return this.GetPropertyAsync<string>();
             }
         }
 
@@ -525,21 +512,7 @@ public void Show()
         public async Task<string> GetAppPathAsync(CancellationToken cancellationToken = default)
         {
             cancellationToken.ThrowIfCancellationRequested();
-
-            var taskCompletionSource = new TaskCompletionSource<string>();
-            using(cancellationToken.Register(() => taskCompletionSource.TrySetCanceled()))
-            {
-                BridgeConnector.Socket.On("appGetAppPathCompleted", (path) =>
-                {
-                    BridgeConnector.Socket.Off("appGetAppPathCompleted");
-                    taskCompletionSource.SetResult(path.ToString());
-                });
-
-                BridgeConnector.Socket.Emit("appGetAppPath");
-
-                return await taskCompletionSource.Task
-                    .ConfigureAwait(false);
-            }            
+            return await this.GetPropertyAsync<string>().ConfigureAwait(false);
         }
 
         /// <summary>
@@ -609,21 +582,7 @@ public void SetPath(PathName name, string path)
         public async Task<string> GetVersionAsync(CancellationToken cancellationToken = default)
         {
             cancellationToken.ThrowIfCancellationRequested();
-
-            var taskCompletionSource = new TaskCompletionSource<string>();
-            using(cancellationToken.Register(() => taskCompletionSource.TrySetCanceled()))
-            {
-                BridgeConnector.Socket.On("appGetVersionCompleted", (version) =>
-                {
-                    BridgeConnector.Socket.Off("appGetVersionCompleted");
-                    taskCompletionSource.SetResult(version.ToString());
-                });
-
-                BridgeConnector.Socket.Emit("appGetVersion");
-
-                return await taskCompletionSource.Task
-                    .ConfigureAwait(false);
-            }
+            return await this.GetPropertyAsync<string>().ConfigureAwait(false);
         }
 
         /// <summary>
@@ -637,21 +596,7 @@ public async Task<string> GetVersionAsync(CancellationToken cancellationToken =
         public async Task<string> GetLocaleAsync(CancellationToken cancellationToken = default)
         {
             cancellationToken.ThrowIfCancellationRequested();
-
-            var taskCompletionSource = new TaskCompletionSource<string>();
-            using (cancellationToken.Register(() => taskCompletionSource.TrySetCanceled()))
-            {
-                BridgeConnector.Socket.On("appGetLocaleCompleted", (local) =>
-                {
-                    BridgeConnector.Socket.Off("appGetLocaleCompleted");
-                    taskCompletionSource.SetResult(local.ToString());
-                });
-
-                BridgeConnector.Socket.Emit("appGetLocale");
-
-                return await taskCompletionSource.Task
-                    .ConfigureAwait(false);
-            }
+            return await this.GetPropertyAsync<string>().ConfigureAwait(false);
         }
 
         /// <summary>
@@ -942,21 +887,7 @@ public async Task<bool> SetUserTasksAsync(UserTask[] userTasks, CancellationToke
         public async Task<JumpListSettings> GetJumpListSettingsAsync(CancellationToken cancellationToken = default)
         {
             cancellationToken.ThrowIfCancellationRequested();
-
-            var taskCompletionSource = new TaskCompletionSource<JumpListSettings>();
-            using (cancellationToken.Register(() => taskCompletionSource.TrySetCanceled()))
-            {
-                BridgeConnector.Socket.On("appGetJumpListSettingsCompleted", (jumpListSettings) =>
-                {
-                    BridgeConnector.Socket.Off("appGetJumpListSettingsCompleted");
-                    taskCompletionSource.SetResult(JObject.Parse(jumpListSettings.ToString()).ToObject<JumpListSettings>());
-                });
-
-                BridgeConnector.Socket.Emit("appGetJumpListSettings");
-
-                return await taskCompletionSource.Task
-                    .ConfigureAwait(false);
-            }
+            return await this.GetPropertyAsync<JumpListSettings>().ConfigureAwait(false);
         }
 
         /// <summary>
@@ -1049,21 +980,7 @@ public void ReleaseSingleInstanceLock()
         public async Task<bool> HasSingleInstanceLockAsync(CancellationToken cancellationToken = default)
         {
             cancellationToken.ThrowIfCancellationRequested();
-
-            var taskCompletionSource = new TaskCompletionSource<bool>();
-            using (cancellationToken.Register(() => taskCompletionSource.TrySetCanceled()))
-            {
-                BridgeConnector.Socket.On("appHasSingleInstanceLockCompleted", (hasLock) =>
-                {
-                    BridgeConnector.Socket.Off("appHasSingleInstanceLockCompleted");
-                    taskCompletionSource.SetResult((bool) hasLock);
-                });
-
-                BridgeConnector.Socket.Emit("appHasSingleInstanceLock");
-
-                return await taskCompletionSource.Task
-                    .ConfigureAwait(false);
-            }
+            return await this.GetPropertyAsync<bool>().ConfigureAwait(false);
         }
 
         /// <summary>
@@ -1102,21 +1019,7 @@ public void SetUserActivity(string type, object userInfo, string webpageUrl)
         public async Task<string> GetCurrentActivityTypeAsync(CancellationToken cancellationToken = default)
         {
             cancellationToken.ThrowIfCancellationRequested();
-
-            var taskCompletionSource = new TaskCompletionSource<string>();
-            using (cancellationToken.Register(() => taskCompletionSource.TrySetCanceled()))
-            {
-                BridgeConnector.Socket.On("appGetCurrentActivityTypeCompleted", (activityType) =>
-                {
-                    BridgeConnector.Socket.Off("appGetCurrentActivityTypeCompleted");
-                    taskCompletionSource.SetResult(activityType.ToString());
-                });
-
-                BridgeConnector.Socket.Emit("appGetCurrentActivityType");
-
-                return await taskCompletionSource.Task
-                    .ConfigureAwait(false);
-            }
+            return await this.GetPropertyAsync<string>().ConfigureAwait(false);
         }
 
         /// <summary>
@@ -1184,23 +1087,7 @@ public async Task<int> ImportCertificateAsync(ImportCertificateOptions options,
         public async Task<ProcessMetric[]> GetAppMetricsAsync(CancellationToken cancellationToken = default)
         {
             cancellationToken.ThrowIfCancellationRequested();
-
-            var taskCompletionSource = new TaskCompletionSource<ProcessMetric[]>();
-            using (cancellationToken.Register(() => taskCompletionSource.TrySetCanceled()))
-            {
-                BridgeConnector.Socket.On("appGetAppMetricsCompleted", (result) =>
-                {
-                    BridgeConnector.Socket.Off("appGetAppMetricsCompleted");
-                    var processMetrics = ((JArray)result).ToObject<ProcessMetric[]>();
-
-                    taskCompletionSource.SetResult(processMetrics);
-                });
-
-                BridgeConnector.Socket.Emit("appGetAppMetrics");
-
-                return await taskCompletionSource.Task
-                    .ConfigureAwait(false);
-            }
+            return await this.GetPropertyAsync<ProcessMetric[]>().ConfigureAwait(false);
         }
 
         /// <summary>
@@ -1212,23 +1099,7 @@ public async Task<ProcessMetric[]> GetAppMetricsAsync(CancellationToken cancella
         public async Task<GPUFeatureStatus> GetGpuFeatureStatusAsync(CancellationToken cancellationToken = default)
         {
             cancellationToken.ThrowIfCancellationRequested();
-
-            var taskCompletionSource = new TaskCompletionSource<GPUFeatureStatus>();
-            using (cancellationToken.Register(() => taskCompletionSource.TrySetCanceled()))
-            {
-                BridgeConnector.Socket.On("appGetGpuFeatureStatusCompleted", (result) =>
-                {
-                    BridgeConnector.Socket.Off("appGetGpuFeatureStatusCompleted");
-                    var gpuFeatureStatus = ((JObject)result).ToObject<GPUFeatureStatus>();
-
-                    taskCompletionSource.SetResult(gpuFeatureStatus);
-                });
-
-                BridgeConnector.Socket.Emit("appGetGpuFeatureStatus");
-
-                return await taskCompletionSource.Task
-                    .ConfigureAwait(false);
-            }
+            return await this.GetPropertyAsync<GPUFeatureStatus>().ConfigureAwait(false);
         }
 
         /// <summary>
@@ -1268,21 +1139,7 @@ public async Task<bool> SetBadgeCountAsync(int count, CancellationToken cancella
         public async Task<int> GetBadgeCountAsync(CancellationToken cancellationToken = default)
         {
             cancellationToken.ThrowIfCancellationRequested();
-
-            var taskCompletionSource = new TaskCompletionSource<int>();
-            using (cancellationToken.Register(() => taskCompletionSource.TrySetCanceled()))
-            {
-                BridgeConnector.Socket.On("appGetBadgeCountCompleted", (count) =>
-                {
-                    BridgeConnector.Socket.Off("appGetBadgeCountCompleted");
-                    taskCompletionSource.SetResult((int)count);
-                });
-
-                BridgeConnector.Socket.Emit("appGetBadgeCount");
-
-                return await taskCompletionSource.Task
-                    .ConfigureAwait(false);
-            }
+            return await this.GetPropertyAsync<int>().ConfigureAwait(false);
         }
 
         /// <summary>
@@ -1297,21 +1154,7 @@ public async Task<int> GetBadgeCountAsync(CancellationToken cancellationToken =
         public async Task<bool> IsUnityRunningAsync(CancellationToken cancellationToken = default)
         {
             cancellationToken.ThrowIfCancellationRequested();
-
-            var taskCompletionSource = new TaskCompletionSource<bool>();
-            using (cancellationToken.Register(() => taskCompletionSource.TrySetCanceled()))
-            {
-                BridgeConnector.Socket.On("appIsUnityRunningCompleted", (isUnityRunning) =>
-                {
-                    BridgeConnector.Socket.Off("appIsUnityRunningCompleted");
-                    taskCompletionSource.SetResult((bool)isUnityRunning);
-                });
-
-                BridgeConnector.Socket.Emit("appIsUnityRunning");
-
-                return await taskCompletionSource.Task
-                    .ConfigureAwait(false);
-            }
+            return await this.GetPropertyAsync<bool>().ConfigureAwait(false);
         }
 
         /// <summary>
@@ -1379,21 +1222,7 @@ public void SetLoginItemSettings(LoginSettings loginSettings)
         public async Task<bool> IsAccessibilitySupportEnabledAsync(CancellationToken cancellationToken = default)
         {
             cancellationToken.ThrowIfCancellationRequested();
-
-            var taskCompletionSource = new TaskCompletionSource<bool>();
-            using (cancellationToken.Register(() => taskCompletionSource.TrySetCanceled()))
-            {
-                BridgeConnector.Socket.On("appIsAccessibilitySupportEnabledCompleted", (isAccessibilitySupportEnabled) =>
-                {
-                    BridgeConnector.Socket.Off("appIsAccessibilitySupportEnabledCompleted");
-                    taskCompletionSource.SetResult((bool)isAccessibilitySupportEnabled);
-                });
-
-                BridgeConnector.Socket.Emit("appIsAccessibilitySupportEnabled");
-
-                return await taskCompletionSource.Task
-                    .ConfigureAwait(false);
-            }
+            return await this.GetPropertyAsync<bool>().ConfigureAwait(false);
         }
 
         /// <summary>
@@ -1469,20 +1298,7 @@ public Task<string> UserAgentFallbackAsync
         {
             get
             {
-                return Task.Run<string>(() =>
-                {
-                    var taskCompletionSource = new TaskCompletionSource<string>();
-
-                    BridgeConnector.Socket.On("appGetUserAgentFallbackCompleted", (result) =>
-                    {
-                        BridgeConnector.Socket.Off("appGetUserAgentFallbackCompleted");
-                        taskCompletionSource.SetResult((string)result);
-                    });
-
-                    BridgeConnector.Socket.Emit("appGetUserAgentFallback");
-
-                    return taskCompletionSource.Task;
-                });
+                return this.GetPropertyAsync<string>();
             }
         }