Latest Proxy version is broken when route is to the root of the function app

Azure/Azure-Functions#505

Author: safihamid

src/WebJobs.Script.WebHost/App_Start/WebApiConfig.cs

@@ -58,11 +58,6 @@ public static void Register(HttpConfiguration config, ScriptSettingsManager sett
             // Web API routes
             config.MapHttpAttributeRoutes();
 
-            config.Routes.MapHttpRoute(
-                name: "Home",
-                routeTemplate: string.Empty,
-                defaults: new { controller = "Home" });
-
             config.Routes.MapHttpRoute(
                 name: "Functions",
                 routeTemplate: "{*uri}",

src/WebJobs.Script.WebHost/Controllers/FunctionsController.cs

@@ -5,6 +5,7 @@
 using System.IO;
 using System.Net;
 using System.Net.Http;
+using System.Text;
 using System.Threading;
 using System.Threading.Tasks;
 using System.Web.Http;
@@ -13,6 +14,7 @@
 using Microsoft.Azure.WebJobs.Extensions.Http;
 using Microsoft.Azure.WebJobs.Script.Description;
 using Microsoft.Azure.WebJobs.Script.WebHost.Filters;
+using Microsoft.Azure.WebJobs.Script.WebHost.Properties;
 using Microsoft.Azure.WebJobs.Script.WebHost.WebHooks;
 
 namespace Microsoft.Azure.WebJobs.Script.WebHost.Controllers
@@ -31,15 +33,37 @@ public FunctionsController(WebScriptHostManager scriptHostManager, WebHookReceiv
             _webHookReceiverManager = webHookReceiverManager;
         }
 
+        private static bool IsHomepageDisabled
+        {
+            get
+            {
+                return string.Equals(Environment.GetEnvironmentVariable(EnvironmentSettingNames.AzureWebJobsDisableHomepage),
+                    bool.TrueString, StringComparison.OrdinalIgnoreCase);
+            }
+        }
+
         public override async Task<HttpResponseMessage> ExecuteAsync(HttpControllerContext controllerContext, CancellationToken cancellationToken)
         {
             var request = controllerContext.Request;
             var function = _scriptHostManager.GetHttpFunctionOrNull(request);
             if (function == null)
             {
+                if (request.RequestUri.AbsolutePath == "/")
+                {
+                    // if the request is to the root and we can't find any matching FunctionDescriptors which might have been setup by proxies
+                    // then homepage logic will be applied.
+                    return IsHomepageDisabled
+                        ? new HttpResponseMessage(HttpStatusCode.NoContent)
+                        : new HttpResponseMessage(HttpStatusCode.OK)
+                        {
+                            Content = new StringContent(Resources.Homepage, Encoding.UTF8, "text/html")
+                        };
+                }
+
                 // request does not map to an HTTP function
                 return new HttpResponseMessage(HttpStatusCode.NotFound);
             }
+
             request.SetProperty(ScriptConstants.AzureFunctionsHttpFunctionKey, function);
 
             var authorizationLevel = await DetermineAuthorizationLevelAsync(request, function, controllerContext.Configuration.DependencyResolver);

src/WebJobs.Script.WebHost/Controllers/HomeController.cs

@@ -10,7 +10,6 @@
 
 [assembly: System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Naming", "CA1707:IdentifiersShouldNotContainUnderscores", Scope = "namespace", Target = "WebJobs.Script.WebHost.App_Start")]
 [assembly: System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Reliability", "CA2000:Dispose objects before losing scope", Scope = "member", Target = "WebJobs.Script.WebHost.App_Start.AutofacBootstrap.#Initialize(Autofac.ContainerBuilder)")]
-[assembly: System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Performance", "CA1822:MarkMembersAsStatic", Scope = "member", Target = "WebJobs.Script.WebHost.Controllers.HomeController.#Get()")]
 [assembly: System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Design", "CA1018:MarkAttributesWithAttributeUsage", Scope = "type", Target = "WebJobs.Script.WebHost.Filters.AuthorizationLevelAttribute")]
 [assembly: System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Performance", "CA1822:MarkMembersAsStatic", Scope = "member", Target = "WebJobs.Script.WebHost.WebApiApplication.#Application_Start()")]
 [assembly: System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Performance", "CA1811:AvoidUncalledPrivateCode", Scope = "member", Target = "WebJobs.Script.WebHost.WebApiApplication.#Application_Error(System.Object,System.EventArgs)")]
@@ -28,7 +27,6 @@
 [assembly: System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Naming", "CA1709:IdentifiersShouldBeCasedCorrectly", MessageId = "Ms", Scope = "member", Target = "WebJobs.Script.WebHost.Diagnostics.IMetricsEventGenerator.#RaiseMetricsPerFunctionEvent(System.String,System.String,System.Int64,System.Int64,System.Int64,System.Int64)")]
 [assembly: System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Naming", "CA1704:IdentifiersShouldBeSpelledCorrectly", MessageId = "Ms", Scope = "member", Target = "WebJobs.Script.WebHost.Diagnostics.IMetricsEventGenerator.#RaiseMetricsPerFunctionEvent(System.String,System.String,System.Int64,System.Int64,System.Int64,System.Int64)")]
 [assembly: System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Reliability", "CA2000:Dispose objects before losing scope", Scope = "member", Target = "Microsoft.Azure.WebJobs.Script.WebHost.AutofacBootstrap.#Initialize(Autofac.ContainerBuilder,Microsoft.Azure.WebJobs.Script.WebHost.WebHostSettings)")]
-[assembly: System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Performance", "CA1822:MarkMembersAsStatic", Scope = "member", Target = "Microsoft.Azure.WebJobs.Script.WebHost.Controllers.HomeController.#Get()")]
 [assembly: System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Design", "CA1030:UseEventsWhereAppropriate", Scope = "member", Target = "Microsoft.Azure.WebJobs.Script.WebHost.Diagnostics.IMetricsEventGenerator.#RaiseFunctionsMetricEvent(System.String,System.Int64,System.Int64,System.String)")]
 [assembly: System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Naming", "CA1709:IdentifiersShouldBeCasedCorrectly", MessageId = "Ms", Scope = "member", Target = "Microsoft.Azure.WebJobs.Script.WebHost.Diagnostics.IMetricsEventGenerator.#RaiseMetricsPerFunctionEvent(System.String,System.String,System.Int64,System.Int64,System.Int64,System.Int64)")]
 [assembly: System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Naming", "CA1704:IdentifiersShouldBeSpelledCorrectly", MessageId = "Ms", Scope = "member", Target = "Microsoft.Azure.WebJobs.Script.WebHost.Diagnostics.IMetricsEventGenerator.#RaiseMetricsPerFunctionEvent(System.String,System.String,System.Int64,System.Int64,System.Int64,System.Int64)")]
@@ -71,8 +69,6 @@
 [assembly: System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Usage", "CA2227:CollectionPropertiesShouldBeReadOnly", Scope = "member", Target = "Microsoft.Azure.WebJobs.Script.WebHost.Models.ApiModel.#Links")]
 [assembly: System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Performance", "CA1810:InitializeReferenceTypeStaticFieldsInline", Scope = "member", Target = "Microsoft.Azure.WebJobs.Script.WebHost.Models.ApiModelUtility.#.cctor()")]
 [assembly: System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Reliability", "CA2000:Dispose objects before losing scope", Scope = "member", Target = "Microsoft.Azure.WebJobs.Script.WebHost.SecretManager.#.ctor(System.String,Microsoft.Azure.WebJobs.Script.WebHost.IKeyValueConverterFactory,System.Boolean)")]
-[assembly: System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Performance", "CA1822:MarkMembersAsStatic", Scope = "member", Target = "Microsoft.Azure.WebJobs.Script.WebHost.Controllers.HomeController.#IsHomePageDisabled")]
-[assembly: System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Reliability", "CA2000:Dispose objects before losing scope", Scope = "member", Target = "Microsoft.Azure.WebJobs.Script.WebHost.Controllers.HomeController.#Get()")]
 [assembly: System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Performance", "CA1810:InitializeReferenceTypeStaticFieldsInline", Scope = "member", Target = "Microsoft.Azure.WebJobs.Script.WebHost.Models.ApiModelUtility.#.cctor()")]
 [assembly: System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Reliability", "CA2000:Dispose objects before losing scope", Scope = "member", Target = "Microsoft.Azure.WebJobs.Script.WebHost.WebHostResolver.#GetSecretManager(Microsoft.Azure.WebJobs.Script.Settings.ScriptSettingsManager,System.String)")]
 [assembly: System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Reliability", "CA2000:Dispose objects before losing scope", Scope = "member", Target = "Microsoft.Azure.WebJobs.Script.WebHost.WebHostResolver.#GetSecretManager(Microsoft.Azure.WebJobs.Script.Config.ScriptSettingsManager,System.String)")]

src/WebJobs.Script.WebHost/GlobalSuppressions.cs

@@ -470,7 +470,6 @@
     <Compile Include="StandbyManager.cs" />
     <Compile Include="Controllers\AdminController.cs" />
     <Compile Include="Controllers\FunctionsController.cs" />
-    <Compile Include="Controllers\HomeController.cs" />
     <Compile Include="Controllers\KeysController.cs" />
     <Compile Include="Filters\JwtAuthenticationAttribute.cs" />
     <Compile Include="Handlers\ExceptionProcessingHandler.cs" />

src/WebJobs.Script.WebHost/WebJobs.Script.WebHost.csproj

@@ -1251,9 +1251,11 @@ internal static void ValidateFunction(FunctionDescriptor function, Dictionary<st
             var httpTrigger = function.GetTriggerAttributeOrNull<HttpTriggerAttribute>();
             if (httpTrigger != null)
             {
-                ValidateHttpFunction(function.Name, httpTrigger);
+                bool isProxy = function.Metadata != null && function.Metadata.IsProxy;
 
-                if (function.Metadata != null && !function.Metadata.IsProxy)
+                ValidateHttpFunction(function.Name, httpTrigger, isProxy);
+
+                if (!isProxy)
                 {
                     // prevent duplicate/conflicting routes for functions
                     // proxy routes check is done in the proxy dll itself and proxies do not use routePrefix so should not check conflict with functions
@@ -1270,9 +1272,9 @@ internal static void ValidateFunction(FunctionDescriptor function, Dictionary<st
             }
         }
 
-        internal static void ValidateHttpFunction(string functionName, HttpTriggerAttribute httpTrigger)
+        internal static void ValidateHttpFunction(string functionName, HttpTriggerAttribute httpTrigger, bool isProxy = false)
         {
-            if (string.IsNullOrWhiteSpace(httpTrigger.Route))
+            if (string.IsNullOrWhiteSpace(httpTrigger.Route) && !isProxy)
             {
                 // if no explicit route is provided, default to the function name
                 httpTrigger.Route = functionName;