From 338e1e0d6dcb2fbac569e72661ce89201e733c1d Mon Sep 17 00:00:00 2001
From: Zeegaan <70372949+Zeegaan@users.noreply.github.com>
Date: Tue, 3 Aug 2021 14:04:19 +0200
Subject: [PATCH] https://github.com/umbraco/Umbraco-CMS/issues/10699 Changed
 HasSet<Uri> to ConcurrentHashSet<Uri> and changed Add method to TryAdd in
 AspNetCoreHostingEnviroment.EnsureApplicationMainUrl() to fix concurrency
 errors

---
 .../AspNetCoreHostingEnvironmentTests.cs             | 11 +++++++++++
 .../AspNetCore/AspNetCoreHostingEnvironment.cs       | 12 ++++++++----
 2 files changed, 19 insertions(+), 4 deletions(-)

diff --git a/src/Umbraco.Tests.UnitTests/Umbraco.Web.Website/AspNetCoreHostingEnvironmentTests.cs b/src/Umbraco.Tests.UnitTests/Umbraco.Web.Website/AspNetCoreHostingEnvironmentTests.cs
index fe9796251e..b0400f5e96 100644
--- a/src/Umbraco.Tests.UnitTests/Umbraco.Web.Website/AspNetCoreHostingEnvironmentTests.cs
+++ b/src/Umbraco.Tests.UnitTests/Umbraco.Web.Website/AspNetCoreHostingEnvironmentTests.cs
@@ -2,6 +2,7 @@
 // See LICENSE for more details.
 
 using System;
+using System.Threading.Tasks;
 using NUnit.Framework;
 using Umbraco.Cms.Core.Strings;
 using Umbraco.Cms.Tests.UnitTests.AutoFixture;
@@ -36,5 +37,15 @@ namespace Umbraco.Cms.Tests.UnitTests.Umbraco.Web.Website
             Assert.AreEqual("~/Views/Template.cshtml", PathUtility.EnsurePathIsApplicationRootPrefixed("/Views/Template.cshtml"));
             Assert.AreEqual("~/Views/Template.cshtml", PathUtility.EnsurePathIsApplicationRootPrefixed("~/Views/Template.cshtml"));
         }
+
+        [AutoMoqData]
+        [Test]
+        public void EnsureApplicationMainUrl(AspNetCoreHostingEnvironment sut)
+        {
+            var url = new Uri("http://localhost:5000");
+            sut.EnsureApplicationMainUrl(url);
+            Assert.AreEqual(sut.ApplicationMainUrl, url);
+
+        }
     }
 }
diff --git a/src/Umbraco.Web.Common/AspNetCore/AspNetCoreHostingEnvironment.cs b/src/Umbraco.Web.Common/AspNetCore/AspNetCoreHostingEnvironment.cs
index 2689f6f6b3..4ab50ecdc1 100644
--- a/src/Umbraco.Web.Common/AspNetCore/AspNetCoreHostingEnvironment.cs
+++ b/src/Umbraco.Web.Common/AspNetCore/AspNetCoreHostingEnvironment.cs
@@ -1,9 +1,11 @@
 using System;
 using System.Collections.Generic;
 using System.IO;
+using System.Threading;
 using Microsoft.AspNetCore.DataProtection;
 using Microsoft.AspNetCore.Hosting;
 using Microsoft.Extensions.Options;
+using Umbraco.Cms.Core.Collections;
 using Umbraco.Cms.Core.Configuration;
 using Umbraco.Cms.Core.Configuration.Models;
 using Umbraco.Extensions;
@@ -13,7 +15,7 @@ namespace Umbraco.Cms.Web.Common.AspNetCore
 {
     public class AspNetCoreHostingEnvironment : IHostingEnvironment
     {
-        private readonly ISet<Uri> _applicationUrls = new HashSet<Uri>();
+        private readonly ConcurrentHashSet<Uri> _applicationUrls = new ConcurrentHashSet<Uri>();
         private readonly IServiceProvider _serviceProvider;
         private readonly IOptionsMonitor<HostingSettings> _hostingSettings;
         private readonly IOptionsMonitor<WebRoutingSettings> _webRoutingSettings;
@@ -168,6 +170,7 @@ namespace Umbraco.Cms.Web.Common.AspNetCore
             // (this is a simplified version of what was in 7.x)
             // note: should this be optional? is it expensive?
 
+            
             if (currentApplicationUrl is null)
             {
                 return;
@@ -181,9 +184,10 @@ namespace Umbraco.Cms.Web.Common.AspNetCore
             var change = !_applicationUrls.Contains(currentApplicationUrl);
             if (change)
             {
-                _applicationUrls.Add(currentApplicationUrl);
-
-                ApplicationMainUrl = currentApplicationUrl;
+                if (_applicationUrls.TryAdd(currentApplicationUrl))
+                {
+                    ApplicationMainUrl = currentApplicationUrl;
+                }
             }
         }
     }