From 7f267723e231e064015c5f98cb9e332dbbabc584 Mon Sep 17 00:00:00 2001
From: Alexey Rodionov <alrod@inbox.ru>
Date: Thu, 14 Sep 2023 08:32:11 -0700
Subject: [PATCH] Fixing scaler provider initialization pattern (#38673)

---
 .../Config/EventHubWebJobsBuilderExtensions.cs  | 17 +++--------------
 .../Config/ServiceBusHostBuilderExtensions.cs   | 17 +++--------------
 .../StorageQueuesWebJobsBuilderExtensions.cs    | 17 +++--------------
 3 files changed, 9 insertions(+), 42 deletions(-)

diff --git a/sdk/eventhub/Microsoft.Azure.WebJobs.Extensions.EventHubs/src/Config/EventHubWebJobsBuilderExtensions.cs b/sdk/eventhub/Microsoft.Azure.WebJobs.Extensions.EventHubs/src/Config/EventHubWebJobsBuilderExtensions.cs
index ea86003d8bb1..d8d817dac687 100644
--- a/sdk/eventhub/Microsoft.Azure.WebJobs.Extensions.EventHubs/src/Config/EventHubWebJobsBuilderExtensions.cs
+++ b/sdk/eventhub/Microsoft.Azure.WebJobs.Extensions.EventHubs/src/Config/EventHubWebJobsBuilderExtensions.cs
@@ -94,20 +94,9 @@ public static IWebJobsBuilder AddEventHubs(this IWebJobsBuilder builder, Action<
 
         internal static IWebJobsBuilder AddEventHubsScaleForTrigger(this IWebJobsBuilder builder, TriggerMetadata triggerMetadata)
         {
-            IServiceProvider serviceProvider = null;
-            Lazy<EventHubsScalerProvider> scalerProvider = new Lazy<EventHubsScalerProvider>(() => new EventHubsScalerProvider(serviceProvider, triggerMetadata));
-
-            builder.Services.AddSingleton<IScaleMonitorProvider>(resolvedServiceProvider =>
-            {
-                serviceProvider = serviceProvider ?? resolvedServiceProvider;
-                return scalerProvider.Value;
-            });
-
-            builder.Services.AddSingleton<ITargetScalerProvider>(resolvedServiceProvider =>
-            {
-                serviceProvider = serviceProvider ?? resolvedServiceProvider;
-                return scalerProvider.Value;
-            });
+            builder.Services.AddSingleton(serviceProvider => new EventHubsScalerProvider(serviceProvider, triggerMetadata));
+            builder.Services.AddSingleton<IScaleMonitorProvider>(serviceProvider => serviceProvider.GetRequiredService<EventHubsScalerProvider>());
+            builder.Services.AddSingleton<ITargetScalerProvider>(serviceProvider => serviceProvider.GetRequiredService<EventHubsScalerProvider>());
 
             return builder;
         }
diff --git a/sdk/servicebus/Microsoft.Azure.WebJobs.Extensions.ServiceBus/src/Config/ServiceBusHostBuilderExtensions.cs b/sdk/servicebus/Microsoft.Azure.WebJobs.Extensions.ServiceBus/src/Config/ServiceBusHostBuilderExtensions.cs
index 2134c993c75e..a4a710617f04 100644
--- a/sdk/servicebus/Microsoft.Azure.WebJobs.Extensions.ServiceBus/src/Config/ServiceBusHostBuilderExtensions.cs
+++ b/sdk/servicebus/Microsoft.Azure.WebJobs.Extensions.ServiceBus/src/Config/ServiceBusHostBuilderExtensions.cs
@@ -108,20 +108,9 @@ public static IWebJobsBuilder AddServiceBus(this IWebJobsBuilder builder, Action
 
         internal static IWebJobsBuilder AddServiceBusScaleForTrigger(this IWebJobsBuilder builder, TriggerMetadata triggerMetadata)
         {
-            IServiceProvider serviceProvider = null;
-            Lazy<ServiceBusScalerProvider> scalerProvider = new Lazy<ServiceBusScalerProvider>(() => new ServiceBusScalerProvider(serviceProvider, triggerMetadata));
-
-            builder.Services.AddSingleton<IScaleMonitorProvider>(resolvedServiceProvider =>
-            {
-                serviceProvider = serviceProvider ?? resolvedServiceProvider;
-                return scalerProvider.Value;
-            });
-
-            builder.Services.AddSingleton<ITargetScalerProvider>(resolvedServiceProvider =>
-            {
-                serviceProvider = serviceProvider ?? resolvedServiceProvider;
-                return scalerProvider.Value;
-            });
+            builder.Services.AddSingleton(serviceProvider => new ServiceBusScalerProvider(serviceProvider, triggerMetadata));
+            builder.Services.AddSingleton<IScaleMonitorProvider>(serviceProvider => serviceProvider.GetRequiredService<ServiceBusScalerProvider>());
+            builder.Services.AddSingleton<ITargetScalerProvider>(serviceProvider => serviceProvider.GetRequiredService<ServiceBusScalerProvider>());
 
             return builder;
         }
diff --git a/sdk/storage/Microsoft.Azure.WebJobs.Extensions.Storage.Queues/src/StorageQueuesWebJobsBuilderExtensions.cs b/sdk/storage/Microsoft.Azure.WebJobs.Extensions.Storage.Queues/src/StorageQueuesWebJobsBuilderExtensions.cs
index 57d85a61aae4..3fd8b9a905c0 100644
--- a/sdk/storage/Microsoft.Azure.WebJobs.Extensions.Storage.Queues/src/StorageQueuesWebJobsBuilderExtensions.cs
+++ b/sdk/storage/Microsoft.Azure.WebJobs.Extensions.Storage.Queues/src/StorageQueuesWebJobsBuilderExtensions.cs
@@ -74,20 +74,9 @@ public static IWebJobsBuilder AddAzureStorageQueues(this IWebJobsBuilder builder
         /// <returns></returns>
         public static IWebJobsBuilder AddAzureStorageQueuesScaleForTrigger(this IWebJobsBuilder builder, TriggerMetadata triggerMetadata)
         {
-            IServiceProvider serviceProvider = null;
-            Lazy<QueueScalerProvider> scalerProvider = new Lazy<QueueScalerProvider>(() => new QueueScalerProvider(serviceProvider, triggerMetadata));
-
-            builder.Services.AddSingleton<IScaleMonitorProvider>(resolvedServiceProvider =>
-            {
-                serviceProvider = serviceProvider ?? resolvedServiceProvider;
-                return scalerProvider.Value;
-            });
-
-            builder.Services.AddSingleton<ITargetScalerProvider>(resolvedServiceProvider =>
-            {
-                serviceProvider = serviceProvider ?? resolvedServiceProvider;
-                return scalerProvider.Value;
-            });
+            builder.Services.AddSingleton(serviceProvider => new QueueScalerProvider(serviceProvider, triggerMetadata));
+            builder.Services.AddSingleton<IScaleMonitorProvider>(serviceProvider => serviceProvider.GetRequiredService<QueueScalerProvider>());
+            builder.Services.AddSingleton<ITargetScalerProvider>(serviceProvider => serviceProvider.GetRequiredService<QueueScalerProvider>());
 
             return builder;
         }