separating shutdown concerns from dispose concerns as best as reasonable at this time

Author: tanderson-ld

pkgs/sdk/server/src/Internal/DataSources/PollingDataSource.cs

@@ -23,6 +23,9 @@ internal sealed class PollingDataSource : IDataSource
         private readonly Logger _log;
         private CancellationTokenSource _canceller;
 
+        private bool _disposed = false;
+        private readonly AtomicBoolean _shuttingDown = new AtomicBoolean(false);
+
         internal PollingDataSource(
             LdClientContext context,
             IFeatureRequestor featureRequestor,
@@ -128,22 +131,32 @@ private async Task UpdateTaskAsync()
 
         void IDisposable.Dispose()
         {
+            // dispose is currently overloaded with shutdown responsibility, we handle this first
+            Shutdown(null);
+
             Dispose(true);
             GC.SuppressFinalize(this);
         }
 
         private void Dispose(bool disposing)
         {
-            if (disposing)
-            {
-                Shutdown(null);
+            if (_disposed) return;
+
+            if (disposing) {
+                // dispose managed resources if any
+                _featureRequestor.Dispose();
             }
+
+            _disposed = true;
         }
 
         private void Shutdown(DataSourceStatus.ErrorInfo? errorInfo)
         {
+            // Prevent concurrent shutdown calls - only allow the first call to proceed
+            // GetAndSet returns the OLD value, so if it was already true, we return early
+            if (_shuttingDown.GetAndSet(true)) return;
+
             _canceller?.Cancel();
-            _featureRequestor.Dispose();
             _dataSourceUpdates.UpdateStatus(DataSourceState.Off, errorInfo);
         }
 

pkgs/sdk/server/src/Internal/DataSources/StreamingDataSource.cs

@@ -52,6 +52,9 @@ internal class StreamingDataSource : IDataSource
 
         private IEnumerable<KeyValuePair<string, IEnumerable<string>>> _headers;
 
+        private bool _disposed = false;
+        private readonly AtomicBoolean _shuttingDown = new AtomicBoolean(false);
+
         internal delegate IEventSource EventSourceCreator(Uri streamUri,
             HttpConfiguration httpConfig);
 
@@ -104,20 +107,30 @@ public Task<bool> Start()
 
         public void Dispose()
         {
+            // dispose is currently overloaded with shutdown responsibility, we handle this first
+            Shutdown(null);
+
             Dispose(true);
             GC.SuppressFinalize(this);
         }
 
         private void Dispose(bool disposing)
         {
-            if (disposing)
-            {
-                Shutdown(null);
+            if (_disposed) return;
+
+            if (disposing) {
+                // dispose managed resources if any
             }
+
+            _disposed = true;
         }
 
         private void Shutdown(DataSourceStatus.ErrorInfo? errorInfo)
         {
+            // Prevent concurrent shutdown calls - only allow the first call to proceed
+            // GetAndSet returns the OLD value, so if it was already true, we return early
+            if (_shuttingDown.GetAndSet(true)) return;
+
             _es.Close();
             if (_storeStatusMonitoringEnabled)
             {

pkgs/sdk/server/src/Internal/FDv2DataSources/FDv2PollingDataSource.cs

@@ -30,6 +30,9 @@ internal sealed class FDv2PollingDataSource : IDataSource
         private CancellationTokenSource _canceler;
         private string _environmentId;
 
+        private bool _disposed = false;
+        private readonly AtomicBoolean _shuttingDown = new AtomicBoolean(false);
+
         internal FDv2PollingDataSource(
             LdClientContext context,
             IDataSourceUpdates dataSourceUpdates,
@@ -230,21 +233,32 @@ private void ProcessChangeSet(FDv2ChangeSet fdv2ChangeSet)
 
         void IDisposable.Dispose()
         {
+            // dispose is currently overloaded with shutdown responsibility, we handle this first
+            Shutdown(null);
+
             Dispose(true);
             GC.SuppressFinalize(this);
         }
 
         private void Dispose(bool disposing)
         {
-            if (!disposing) return;
+            if (_disposed) return;
 
-            Shutdown(null);
+            if (disposing) {
+                // dispose managed resources if any
+                _requestor.Dispose();
+            }
+
+            _disposed = true;
         }
 
         private void Shutdown(DataSourceStatus.ErrorInfo? errorInfo)
         {
+            // Prevent concurrent shutdown calls - only allow the first call to proceed
+            // GetAndSet returns the OLD value, so if it was already true, we return early
+            if (_shuttingDown.GetAndSet(true)) return;
+
             _canceler?.Cancel();
-            _requestor.Dispose();
             _dataSourceUpdates.UpdateStatus(DataSourceState.Off, errorInfo);
         }
     }

pkgs/sdk/server/src/Internal/FDv2DataSources/FDv2StreamingDataSource.cs

@@ -56,6 +56,9 @@ internal delegate IEventSource EventSourceCreator(Uri streamUri,
         /// </summary>
         private readonly AtomicBoolean _lastStoreUpdateFailed = new AtomicBoolean(false);
 
+        private bool _disposed = false;
+        private readonly AtomicBoolean _shuttingDown = new AtomicBoolean(false);
+
         internal FDv2StreamingDataSource(
             LdClientContext context,
             IDataSourceUpdates dataSourceUpdates,
@@ -102,19 +105,30 @@ internal FDv2StreamingDataSource(
 
         public void Dispose()
         {
+            // dispose is currently overloaded with shutdown responsibility, we handle this first
+            Shutdown(null);
+
             Dispose(true);
             GC.SuppressFinalize(this);
         }
 
         private void Dispose(bool disposing)
         {
-            if (!disposing) return;
+            if (_disposed) return;
 
-            Shutdown(null);
+            if (disposing) {
+                // dispose managed resources if any
+            }
+
+            _disposed = true;
         }
 
         private void Shutdown(DataSourceStatus.ErrorInfo? errorInfo)
         {
+            // Prevent concurrent shutdown calls - only allow the first call to proceed
+            // GetAndSet returns the OLD value, so if it was already true, we return early
+            if (_shuttingDown.GetAndSet(true)) return;
+            
             _es.Close();
             if (_storeStatusMonitoringEnabled)
             {