From f7fbf14a9fd07cbc23a2e448d5126559fcc94ef8 Mon Sep 17 00:00:00 2001
From: Brennan <brecon@microsoft.com>
Date: Tue, 4 Feb 2025 14:30:26 -0800
Subject: [PATCH] fixup

---
 .../AspNetCore/applicationmanager.cpp         | 11 ++++++--
 .../AspNetCore/globalmodule.cpp               | 25 +++++++++++--------
 .../IntegrationTesting.IIS/src/IISDeployer.cs |  3 +--
 3 files changed, 25 insertions(+), 14 deletions(-)

diff --git a/src/Servers/IIS/AspNetCoreModuleV2/AspNetCore/applicationmanager.cpp b/src/Servers/IIS/AspNetCoreModuleV2/AspNetCore/applicationmanager.cpp
index 5f9224e39c76..ae56d4178f34 100644
--- a/src/Servers/IIS/AspNetCoreModuleV2/AspNetCore/applicationmanager.cpp
+++ b/src/Servers/IIS/AspNetCoreModuleV2/AspNetCore/applicationmanager.cpp
@@ -23,9 +23,16 @@ APPLICATION_MANAGER::GetOrCreateApplicationInfo(
 )
 {
     // GetOrCreateApplicationInfo is called from proxymodule when a request is received.
-    // Set this value to indicate that a request has been received so we can disable shutdown logic in OnGlobalApplicationStop
-    m_hasStarted = true;
 
+    PCWSTR pszVariableValue = nullptr;
+    DWORD cbLength = 0;
+    // Check for preload or warmup request, part of the application initialization process, see comments in ASPNET_CORE_GLOBAL_MODULE::OnGlobalApplicationStop for more info
+    if (FAILED(pHttpContext.GetServerVariable("PRELOAD_REQUEST", &pszVariableValue, &cbLength)) &&
+        FAILED(pHttpContext.GetServerVariable("WARMUP_REQUEST", &pszVariableValue, &cbLength)))
+    {
+        // Set this value to indicate that a request has been received so we can disable shutdown logic in OnGlobalApplicationStop
+        m_hasStarted = true;
+    }
     auto &pApplication = *pHttpContext.GetApplication();
 
     // The configuration path is unique for each application and is used for the
diff --git a/src/Servers/IIS/AspNetCoreModuleV2/AspNetCore/globalmodule.cpp b/src/Servers/IIS/AspNetCoreModuleV2/AspNetCore/globalmodule.cpp
index eeb30d71779a..e920072f7684 100644
--- a/src/Servers/IIS/AspNetCoreModuleV2/AspNetCore/globalmodule.cpp
+++ b/src/Servers/IIS/AspNetCoreModuleV2/AspNetCore/globalmodule.cpp
@@ -35,6 +35,9 @@ ASPNET_CORE_GLOBAL_MODULE::OnGlobalStopListening(
     return GL_NOTIFICATION_CONTINUE;
 }
 
+// We prefer shutting down from OnGlobalStopListening as it is called right before the IIS request handler is disabled, which means it'll start queueing requests
+// But if we stopped in OnGlobalApplicationStop then we can start shutting down while the request handler is still active resulting in us returning 503's since we're shutting down.
+// We still need to shutdown in specific cases where OnGlobalStopListening isn't called, like IISExpress or if the app never receives a request (app preload).
 GLOBAL_NOTIFICATION_STATUS
 ASPNET_CORE_GLOBAL_MODULE::OnGlobalApplicationStop(
     IN IHttpApplicationStopProvider* pProvider
@@ -51,17 +54,19 @@ ASPNET_CORE_GLOBAL_MODULE::OnGlobalApplicationStop(
 
     LOG_INFO(L"ASPNET_CORE_GLOBAL_MODULE::OnGlobalApplicationStop");
 
-    if (!g_fInShutdown && !m_shutdown.joinable()
-        && (m_pApplicationManager->IsIISExpress() || !m_pApplicationManager->HasReceivedRequest()))
+    if (!g_fInShutdown && !m_shutdown.joinable())
     {
-        // Apps with preload + always running that don't receive a request before recycle/shutdown will never call OnGlobalStopListening
-        // IISExpress can also close without calling OnGlobalStopListening which is where we usually would trigger shutdown
-        // so we should make sure to shutdown the server in those cases
-        StartShutdown();
-    }
-    else
-    {
-        LOG_INFO(L"Ignoring OnGlobalApplicationStop, OnGlobalStopListening should be called shortly.");
+        if ((m_pApplicationManager->IsIISExpress() || !m_pApplicationManager->HasReceivedRequest()))
+        {
+            // Apps with preload + always running that don't receive a request before recycle/shutdown will never call OnGlobalStopListening
+            // IISExpress can also close without calling OnGlobalStopListening which is where we usually would trigger shutdown
+            // so we should make sure to shutdown the server in those cases
+            StartShutdown();
+        }
+        else
+        {
+            LOG_INFO(L"Ignoring OnGlobalApplicationStop, OnGlobalStopListening has been called or should be called shortly.");
+        }
     }
 
     return GL_NOTIFICATION_CONTINUE;
diff --git a/src/Servers/IIS/IntegrationTesting.IIS/src/IISDeployer.cs b/src/Servers/IIS/IntegrationTesting.IIS/src/IISDeployer.cs
index 3f56b6a7d151..400dc74287e9 100644
--- a/src/Servers/IIS/IntegrationTesting.IIS/src/IISDeployer.cs
+++ b/src/Servers/IIS/IntegrationTesting.IIS/src/IISDeployer.cs
@@ -307,7 +307,7 @@ private static Site FindSite(ServerManager serverManager, string contentRoot)
 
     private void AddTemporaryAppHostConfig(string contentRoot, int port)
     {
-        var multiSite = true;
+        var multiSite = _applicationHostConfig is not null;
         XDocument config;
         if (_applicationHostConfig is not null)
         {
@@ -315,7 +315,6 @@ private void AddTemporaryAppHostConfig(string contentRoot, int port)
         }
         else
         {
-            multiSite = false;
             _configPath = Path.Combine(Path.GetTempPath(), Guid.NewGuid().ToString("D"));
             _applicationHostConfig = Path.Combine(_configPath, "applicationHost.config");
             Directory.CreateDirectory(_configPath);