refactor: Refactor Init and Shutdown (#416)

Signed-off-by: André Silva <[email protected]>

Author: askpt

src/OpenFeature.Contrib.Providers.Flagd/FlagdProvider.cs

@@ -80,7 +80,6 @@ public FlagdProvider(FlagdConfig config)
     internal FlagdProvider(Resolver.Resolver resolver)
     {
         _resolver = resolver;
-        _resolver.Init();
     }
 
     // just for testing, internal but visible in tests
@@ -105,27 +104,15 @@ public static string GetProviderName()
     internal Resolver.Resolver GetResolver() => _resolver;
 
     /// <inheritdoc/>
-    public override Task InitializeAsync(EvaluationContext context, CancellationToken cancellationToken = default)
+    public override async Task InitializeAsync(EvaluationContext context, CancellationToken cancellationToken = default)
     {
-        return Task.Run(async () =>
-        {
-            await _resolver.Init().ConfigureAwait(false);
-        }).ContinueWith((t) =>
-        {
-            if (t.IsFaulted)
-            {
-                throw t.Exception;
-            }
-        });
+        await _resolver.Init().ConfigureAwait(false);
     }
 
     /// <inheritdoc/>
-    public override Task ShutdownAsync(CancellationToken cancellationToken = default)
+    public override async Task ShutdownAsync(CancellationToken cancellationToken = default)
     {
-        return _resolver.Shutdown().ContinueWith((t) =>
-        {
-            if (t.IsFaulted) throw t.Exception;
-        });
+        await _resolver.Shutdown().ConfigureAwait(false);
     }
 
     /// <inheritdoc/>

src/OpenFeature.Contrib.Providers.Flagd/Resolver/InProcess/InProcessResolver.cs

@@ -33,7 +33,6 @@ internal class InProcessResolver : Resolver
     private readonly Mutex _mtx;
     private int _eventStreamRetryBackoff = InitialEventStreamRetryBaseBackoff;
     private readonly FlagdConfig _config;
-    private Thread _handleEventsThread;
     private GrpcChannel _channel;
     private Channel<object> _eventChannel;
     private Model.Metadata _providerMetadata;
@@ -66,29 +65,29 @@ public async Task Init()
     {
         await _jsonSchemaValidator.InitializeAsync().ConfigureAwait(false);
 
-        await Task.Run(() =>
+        var latch = new CountdownEvent(1);
+        var handleEventsThread = new Thread(async () => await HandleEvents(latch).ConfigureAwait(false))
         {
-            var latch = new CountdownEvent(1);
-            _handleEventsThread = new Thread(async () => await HandleEvents(latch).ConfigureAwait(false))
-            {
-                IsBackground = true
-            };
-            _handleEventsThread.Start();
-            latch.Wait();
-        }).ContinueWith((task) =>
-        {
-            if (task.IsFaulted) throw task.Exception;
-        }).ConfigureAwait(false);
+            IsBackground = true
+        };
+        handleEventsThread.Start();
+        await Task.Run(() => latch.Wait()).ConfigureAwait(false);
     }
 
-    public Task Shutdown()
+    public async Task Shutdown()
     {
         _cancellationTokenSource.Cancel();
-        return _channel?.ShutdownAsync().ContinueWith((t) =>
+        try
         {
-            _channel.Dispose();
-            if (t.IsFaulted) throw t.Exception;
-        });
+            if (_channel != null)
+            {
+                await _channel.ShutdownAsync().ConfigureAwait(false);
+            }
+        }
+        finally
+        {
+            _channel?.Dispose();
+        }
     }
 
     public Task<ResolutionDetails<bool>> ResolveBooleanValueAsync(string flagKey, bool defaultValue, EvaluationContext context = null)
@@ -205,7 +204,8 @@ private T BuildClient<T>(FlagdConfig config, Func<GrpcChannel, T> constructorFun
                     var certificate = CertificateLoader.LoadCertificate(config.CertificatePath);
 
 #if NET8_0_OR_GREATER
-                    handler.ServerCertificateCustomValidationCallback = (message, cert, chain, _) => {
+                    handler.ServerCertificateCustomValidationCallback = (message, cert, chain, _) =>
+                    {
                         // the the custom cert to the chain, Build returns a bool if valid.
                         chain.ChainPolicy.TrustMode = X509ChainTrustMode.CustomRootTrust;
                         chain.ChainPolicy.CustomTrustStore.Add(certificate);
@@ -284,7 +284,8 @@ private FlagSyncService.FlagSyncServiceClient BuildClientForPlatform(FlagdConfig
                 {
                     var certificate = CertificateLoader.LoadCertificate(config.CertificatePath);
 #if NET5_0_OR_GREATER
-                    handler.ServerCertificateCustomValidationCallback = (message, cert, chain, _) => {
+                    handler.ServerCertificateCustomValidationCallback = (message, cert, chain, _) =>
+                    {
                         // the the custom cert to the chain, Build returns a bool if valid.
                         chain.ChainPolicy.TrustMode = X509ChainTrustMode.CustomRootTrust;
                         chain.ChainPolicy.CustomTrustStore.Add(certificate);

src/OpenFeature.Contrib.Providers.Flagd/Resolver/Rpc/RpcResolver.cs

@@ -30,7 +30,6 @@ internal class RpcResolver : Resolver
     private GrpcChannel _channel;
     private Channel<object> _eventChannel;
     private Model.Metadata _providerMetadata;
-    private Thread _handleEventsThread;
 
     internal RpcResolver(FlagdConfig config, Channel<object> eventChannel, Model.Metadata providerMetadata)
     {
@@ -59,19 +58,21 @@ internal RpcResolver(Service.ServiceClient client, FlagdConfig config, ICache<st
 
     public Task Init()
     {
-        _handleEventsThread = new Thread(HandleEvents);
-        _handleEventsThread.Start();
-        return Task.CompletedTask; // TODO: an elegant way of testing the connection status before completing this task
+        _ = Task.Run(this.HandleEvents);
+        return Task.CompletedTask;
     }
 
-    public Task Shutdown()
+    public async Task Shutdown()
     {
         _cancellationTokenSource.Cancel();
-        return _channel?.ShutdownAsync().ContinueWith((t) =>
+        try
         {
-            _channel.Dispose();
-            if (t.IsFaulted) throw t.Exception;
-        });
+            await _channel.ShutdownAsync().ConfigureAwait(false);
+        }
+        finally
+        {
+            _channel?.Dispose();
+        }
     }
 
     public async Task<ResolutionDetails<bool>> ResolveBooleanValueAsync(string flagKey, bool defaultValue, EvaluationContext context = null)
@@ -197,7 +198,7 @@ private async Task<ResolutionDetails<T>> ResolveValue<T>(string flagKey, Func<St
         }
     }
 
-    private async void HandleEvents()
+    private async Task HandleEvents()
     {
         CancellationToken token = _cancellationTokenSource.Token;
         while (!token.IsCancellationRequested && _eventStreamRetries < _config.MaxEventStreamRetries)
@@ -452,7 +453,8 @@ private Service.ServiceClient BuildClientForPlatform(FlagdConfig config)
                 {
                     var certificate = CertificateLoader.LoadCertificate(config.CertificatePath);
 #if NET5_0_OR_GREATER
-                    handler.ServerCertificateCustomValidationCallback = (message, cert, chain, _) => {
+                    handler.ServerCertificateCustomValidationCallback = (message, cert, chain, _) =>
+                    {
                         // the the custom cert to the chain, Build returns a bool if valid.
                         chain.ChainPolicy.TrustMode = System.Security.Cryptography.X509Certificates.X509ChainTrustMode.CustomRootTrust;
                         chain.ChainPolicy.CustomTrustStore.Add(certificate);