updte comments

Author: nytian

src/Microsoft.Azure.WebJobs.Extensions.DurableTask.FunctionsScale/AzureStorage/AzureStorageScalabilityProvider.cs

@@ -22,7 +22,7 @@ public class AzureStorageScalabilityProvider : ScalabilityProvider
         private DurableTaskMetricsProvider singletonDurableTaskMetricsProvider;
 
         /// <summary>
-        /// Initializes a new <see cref="AzureStorageScalabilityProvider"/> instance for scaling using Azure Storage.
+        /// Initializes a new instance of the <see cref="AzureStorageScalabilityProvider"/> class.
         /// </summary>
         /// <param name="storageAccountClientProvider">
         /// Provides Azure Storage clients using resolved configuration, including
@@ -41,18 +41,10 @@ public AzureStorageScalabilityProvider(
         }
 
         /// <summary>
-        /// The app setting containing the Azure Storage connection string.
+        /// Gets the app setting containing the Azure Storage connection string.
         /// </summary>
         public override string ConnectionName => this.connectionName;
 
-        internal DurableTaskMetricsProvider GetMetricsProvider(
-            string hubName,
-            StorageAccountClientProvider clientProvider,
-            ILogger metricsLogger)
-        {
-            return new DurableTaskMetricsProvider(hubName, metricsLogger, performanceMonitor: null, clientProvider);
-        }
-
         /// <inheritdoc/>
         /// Note: ScaleMonitor is not used in prod. Can be cleaned in future.
         public override bool TryGetScaleMonitor(
@@ -99,5 +91,13 @@ public override bool TryGetTargetScaler(
                 return true;
             }
         }
+
+        internal DurableTaskMetricsProvider GetMetricsProvider(
+            string hubName,
+            StorageAccountClientProvider clientProvider,
+            ILogger metricsLogger)
+        {
+            return new DurableTaskMetricsProvider(hubName, metricsLogger, performanceMonitor: null, clientProvider);
+        }
     }
 }

src/Microsoft.Azure.WebJobs.Extensions.DurableTask.FunctionsScale/AzureStorage/AzureStorageScalabilityProviderFactory.cs

@@ -15,8 +15,8 @@ namespace Microsoft.Azure.WebJobs.Extensions.DurableTask.FunctionsScale.AzureSto
     /// </summary>
     public class AzureStorageScalabilityProviderFactory : IScalabilityProviderFactory
     {
-        private const string LoggerName = "Triggers.DurableTask.AzureStorage";
         internal const string ProviderName = "AzureStorage";
+        private const string LoggerName = "Triggers.DurableTask.AzureStorage";
 
         private readonly IStorageServiceClientProviderFactory clientProviderFactory;
         private readonly IConfiguration configuration;
@@ -49,12 +49,12 @@ public AzureStorageScalabilityProviderFactory(
         }
 
         /// <summary>
-        /// Name of this provider service.
+        /// Gets name of this provider service.
         /// </summary>
         public virtual string Name => ProviderName;
 
         /// <summary>
-        /// Default connection name of this provider service.
+        /// Gets default connection name of this provider service.
         /// </summary>
         public string DefaultConnectionName { get; }
 

src/Microsoft.Azure.WebJobs.Extensions.DurableTask.FunctionsScale/AzureStorage/DurableTaskMetricsProvider.cs

@@ -39,6 +39,7 @@ public class DurableTaskMetricsProvider
         /// <param name="storageAccountClientProvider">
         /// Provides Azure Storage clients required to access task hub resources.
         /// </param>
+        /// Note: This file should remain partially aligned with Microsoft.Azure.WebJobs.Extensions.DurableTask/Listener/DurableTaskMetricsProvider.
         public DurableTaskMetricsProvider(
             string hubName,
             ILogger logger,

src/Microsoft.Azure.WebJobs.Extensions.DurableTask.FunctionsScale/AzureStorage/DurableTaskScaleMonitor.cs

@@ -13,8 +13,9 @@
 
 namespace Microsoft.Azure.WebJobs.Extensions.DurableTask.FunctionsScale.AzureStorage
 {
-    //TODO: This class can be removed in future. As Scale Controller v3 doesn't use Scale Monitor.
+    // TODO: This class can be removed in future. As Scale Controller v3 doesn't use Scale Monitor.
     // Keep it for now for backwards compatibility.
+    // Note: This file should remain partially aligned with Microsoft.Azure.WebJobs.Extensions.DurableTask/Listener/DurableTaskScaleMonitor.
     internal sealed class DurableTaskScaleMonitor : IScaleMonitor<DurableTaskTriggerMetrics>
     {
         private readonly string hubName;

src/Microsoft.Azure.WebJobs.Extensions.DurableTask.FunctionsScale/AzureStorage/DurableTaskTargetScaler.cs

@@ -14,6 +14,7 @@ namespace Microsoft.Azure.WebJobs.Extensions.DurableTask.FunctionsScale.AzureSto
 {
     /// <summary>
     /// Target scaler that computes the desired worker count based on scale metrics from the Azure Storage backend.
+    /// Note: This file should remain partially aligned with Microsoft.Azure.WebJobs.Extensions.DurableTask/Listener/DurableTaskTargetScaler.
     /// </summary>
     public class DurableTaskTargetScaler : ITargetScaler
     {
@@ -24,7 +25,7 @@ public class DurableTaskTargetScaler : ITargetScaler
         private readonly string scaler;
 
         /// <summary>
-        /// Initializes a new instance of the <see cref="DurableTaskTargetScaler"/>.
+        /// Initializes a new instance of the <see cref="DurableTaskTargetScaler"/> class.
         /// </summary>
         /// <param name="scalerId">
         /// The unique identifier for this target scaler.

src/Microsoft.Azure.WebJobs.Extensions.DurableTask.FunctionsScale/AzureStorage/DurableTaskTriggerMetrics.cs

@@ -1,41 +1,37 @@
 // Copyright (c) .NET Foundation. All rights reserved.
 // Licensed under the MIT License. See LICENSE in the project root for license information.
-using System.Collections.Generic;
 using Microsoft.Azure.WebJobs.Host.Scale;
 
 namespace Microsoft.Azure.WebJobs.Extensions.DurableTask.FunctionsScale.AzureStorage
 {
     /// <summary>
     /// Represents scale-related metrics for AzureStorage backend.
+    /// Note: This file should remain partially aligned with Microsoft.Azure.WebJobs.Extensions.DurableTask/Listener/DurableTaskTriggerMetrics.
     /// </summary>
     public class DurableTaskTriggerMetrics : ScaleMetrics
     {
         /// <summary>
-        /// The number of partitions in the task hub.
+        /// Gets or sets the number of partitions in the task hub.
         /// </summary>
         public virtual int PartitionCount { get; set; }
 
         /// <summary>
-        /// The number of messages across control queues. This will
-        /// be in the form of a serialized array of ints, e.g. "[1,2,3,4]".
+        /// Gets or sets the number of messages across control queues.
         /// </summary>
         public virtual string ControlQueueLengths { get; set; }
 
         /// <summary>
-        /// The latency of messages across control queues. This will
-        /// be in the form of a serialized array of TimeSpans in string
-        /// format, e.g. "["00:00:00.0010000","00:00:00.0020000","00:00:00.0030000","00:00:00.0040000"]".
+        /// Gets or sets the latency of messages across control queues.
         /// </summary>
         public string ControlQueueLatencies { get; set; }
 
         /// <summary>
-        /// The number of messages in the work-item queue.
+        /// Gets or sets the number of messages in the work-item queue.
         /// </summary>
         public virtual int WorkItemQueueLength { get; set; }
 
         /// <summary>
-        /// The approximate age of the first work-item queue message. This
-        /// will be a TimeSpan in string format, e.g. "00:00:00.0010000".
+        /// Gets or sets the approximate age of the first work-item queue message.
         /// </summary>
         public string WorkItemQueueLatency { get; set; }
     }

src/Microsoft.Azure.WebJobs.Extensions.DurableTask.FunctionsScale/DurableTaskScaleExtension.cs

@@ -29,18 +29,6 @@ public DurableTaskScaleExtension(ILoggerFactory loggerFactory)
             this.logger.LogInformation("DurableTaskScaleExtension initialized.");
         }
 
-        /// <summary>
-        /// Initializes the extension. Called by the WebJobs framework during host startup.
-        /// </summary>
-        /// <param name="context">The extension configuration context.</param>
-        public void Initialize(ExtensionConfigContext context)
-        {
-            // The actual scaling work is done by DurableTaskTriggersScaleProvider.
-            // This extension just needs to exist for the WebJobs framework to properly
-            // initialize the host lifecycle.
-            this.logger.LogInformation("DurableTaskScaleExtension.Initialize called.");
-        }
-
         /// <summary>
         /// Determines the scalability provider factory based on the given metadata.
         /// If no storage provider type is configured, defaults to AzureStorage.
@@ -83,5 +71,17 @@ public static IScalabilityProviderFactory GetScalabilityProviderFactory(
                 throw new InvalidOperationException($"Storage provider type ({storageType?.ToString() ?? "null"}) was not found. Available storage providers: {string.Join(", ", factoryNames)}.", e);
             }
         }
+
+        /// <summary>
+        /// Initializes the extension. Called by the WebJobs framework during host startup.
+        /// </summary>
+        /// <param name="context">The extension configuration context.</param>
+        public void Initialize(ExtensionConfigContext context)
+        {
+            // The actual scaling work is done by DurableTaskTriggersScaleProvider.
+            // This extension just needs to exist for the WebJobs framework to properly
+            // initialize the host lifecycle.
+            this.logger.LogInformation("DurableTaskScaleExtension.Initialize called.");
+        }
     }
 }

src/Microsoft.Azure.WebJobs.Extensions.DurableTask.FunctionsScale/DurableTaskTriggersScaleProvider.cs

@@ -74,7 +74,7 @@ public DurableTaskTriggersScaleProvider(
             ScalabilityProvider defaultscalabilityProvider = scalabilityProviderFactory.GetScalabilityProvider(metadata, triggerMetadata);
 
             // Get connection name from metadata.StorageProvider
-            string? connectionName = GetConnectionNameFromOptions(metadata.StorageProvider) ?? scalabilityProviderFactory.DefaultConnectionName;
+            string? connectionName = TriggerMetadataExtensions.ResolveConnectionName(metadata.StorageProvider) ?? scalabilityProviderFactory.DefaultConnectionName;
 
             logger.LogInformation(
                 "Creating DurableTaskTriggersScaleProvider for function {FunctionName}: connectionName = '{ConnectionName}'",
@@ -96,28 +96,6 @@ public DurableTaskTriggersScaleProvider(
                 metadata.TaskHubName);
         }
 
-        private static string? GetConnectionNameFromOptions(IDictionary<string, object>? storageProvider)
-        {
-            if (storageProvider == null)
-            {
-                return null;
-            }
-
-            // Try connectionName first
-            if (storageProvider.TryGetValue(DefaultConnectionName, out object? value1) && value1 is string s1 && !string.IsNullOrWhiteSpace(s1))
-            {
-                return s1;
-            }
-
-            // Try connectionStringName
-            if (storageProvider.TryGetValue(ConnectionNameOverride, out object? value2) && value2 is string s2 && !string.IsNullOrWhiteSpace(s2))
-            {
-                return s2;
-            }
-
-            return null;
-        }
-
         /// <summary>
         /// Gets the scale monitor used to observe load and trigger scaling decisions.
         /// </summary>

src/Microsoft.Azure.WebJobs.Extensions.DurableTask.FunctionsScale/IScalabilityProviderFactory.cs

@@ -12,7 +12,7 @@ namespace Microsoft.Azure.WebJobs.Extensions.DurableTask.FunctionsScale
     public interface IScalabilityProviderFactory
     {
         /// <summary>
-        /// Specifies the Durability Provider Factory name.
+        /// Gets the provider factory name.
         /// </summary>
         string Name { get; }
 
@@ -23,16 +23,12 @@ public interface IScalabilityProviderFactory
 
         /// <summary>
         /// Creates or retrieves a cached scalability provider.
-        /// This method is used for both runtime-driven scaling and Scale Controller scenarios.
         /// </summary>
         /// <param name="metadata">
         /// The Durable Task metadata containing task hub name, max concurrency settings, and storage provider configuration.
-        /// For runtime-driven scaling: constructed from DurableTaskOptions (host.json).
-        /// For Scale Controller: deserialized from SyncTriggers payload.
         /// </param>
         /// <param name="triggerMetadata">
-        /// Trigger metadata used to access Properties like token credentials (Scale Controller only).
-        /// This is null for runtime-driven scaling since it runs in the host process.
+        /// Trigger metadata provided by Scale Controller to access Properties like token credentials.
         /// </param>
         /// <returns>A scalability provider configured with the specified metadata.</returns>
         ScalabilityProvider GetScalabilityProvider(DurableTaskMetadata metadata, TriggerMetadata? triggerMetadata);

src/Microsoft.Azure.WebJobs.Extensions.DurableTask.FunctionsScale/StorageServiceClientProviderFactory.cs

@@ -10,7 +10,7 @@
 namespace Microsoft.Azure.WebJobs.Extensions.DurableTask.FunctionsScale
 {
     /// <summary>
-    /// Factory for creating azure storage client providers.
+    /// Factory for creating Azure Storage client providers for authenticating with the Azure Storage backend.
     /// </summary>
     public class StorageServiceClientProviderFactory : IStorageServiceClientProviderFactory
     {