Updates to JobHost CORS support

Author: fabiocav

src/WebJobs.Script.WebHost/Configuration/CorsOptionsSetup.cs

@@ -23,7 +23,7 @@ public CorsOptionsSetup(IEnvironment env, IOptions<HostCorsOptions> hostCorsOpti
 
         public void Configure(CorsOptions options)
         {
-            if (_env.IsLinuxConsumption() && _hostCorsOptions.Value != null)
+            if (_env.IsLinuxConsumption())
             {
                 string[] allowedOrigins = _hostCorsOptions.Value.AllowedOrigins?.ToArray() ?? Array.Empty<string>();
                 var policyBuilder = new CorsPolicyBuilder(allowedOrigins);

src/WebJobs.Script.WebHost/Middleware/CorsConfigurationMiddleware.cs

@@ -6,28 +6,27 @@
 using Microsoft.AspNetCore.Cors.Infrastructure;
 using Microsoft.AspNetCore.Http;
 using Microsoft.Azure.WebJobs.Script.WebHost.Configuration;
+using Microsoft.Extensions.Logging;
 using Microsoft.Extensions.Options;
 
 namespace Microsoft.Azure.WebJobs.Script.WebHost.Middleware
 {
     public class CorsMiddlewareFactory : ICorsMiddlewareFactory
     {
         private readonly IOptions<CorsOptions> _corsOptions;
+        private readonly ILoggerFactory _loggerFactory;
 
-        public CorsMiddlewareFactory(IOptions<CorsOptions> corsOptions)
+        public CorsMiddlewareFactory(IOptions<CorsOptions> corsOptions, ILoggerFactory loggerFactory)
         {
             _corsOptions = corsOptions;
+            _loggerFactory = loggerFactory;
         }
 
         public CorsMiddleware CreateCorsMiddleware(RequestDelegate next, IOptions<HostCorsOptions> corsOptions)
         {
-            CorsMiddleware middleware = null;
-            if (corsOptions?.Value != null)
-            {
-                var corsService = new CorsService(_corsOptions);
-                var policy = _corsOptions.Value.GetPolicy(_corsOptions.Value.DefaultPolicyName);
-                middleware = new CorsMiddleware(next, corsService, policy);
-            }
+            CorsPolicy policy = _corsOptions.Value.GetPolicy(_corsOptions.Value.DefaultPolicyName);
+            var corsService = new CorsService(_corsOptions);
+            var middleware = new CorsMiddleware(next, corsService, policy, _loggerFactory);
 
             return middleware;
         }

src/WebJobs.Script.WebHost/Middleware/CorsMiddlewareFactory.cs

@@ -0,0 +1,38 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the MIT License. See License.txt in the project root for license information.
+
+using System.Collections.Generic;
+using System.Threading.Tasks;
+using Microsoft.AspNetCore.Cors.Infrastructure;
+using Microsoft.AspNetCore.Http;
+using Microsoft.Azure.WebJobs.Script.Middleware;
+using Microsoft.Azure.WebJobs.Script.WebHost.Configuration;
+using Microsoft.Extensions.Options;
+
+namespace Microsoft.Azure.WebJobs.Script.WebHost.Middleware
+{
+    public class JobHostCorsMiddleware : IJobHostHttpMiddleware
+    {
+        private readonly CorsMiddleware _corsMiddleware;
+
+        public JobHostCorsMiddleware(IOptions<HostCorsOptions> hostCorsOptions, ICorsMiddlewareFactory middlewareFactory)
+        {
+            _corsMiddleware = middlewareFactory.CreateCorsMiddleware(InvokeNext, hostCorsOptions);
+        }
+
+        public async Task Invoke(HttpContext context, RequestDelegate next)
+        {
+            context.Items.Add(ScriptConstants.CorsMiddlewareRequestDelegate, next);
+
+            await _corsMiddleware.Invoke(context);
+        }
+
+        private async Task InvokeNext(HttpContext context)
+        {
+            if (context.Items.Remove(ScriptConstants.CorsMiddlewareRequestDelegate, out object requestDelegate) && requestDelegate is RequestDelegate next)
+            {
+                await next(context);
+            }
+        }
+    }
+}

src/WebJobs.Script.WebHost/Middleware/JobHostCorsMiddleware.cs

@@ -88,9 +88,8 @@ public static IHostBuilder AddWebScriptHost(this IHostBuilder builder, IServiceP
                     services.TryAddEnumerable(ServiceDescriptor.Singleton<IJobHostHttpMiddleware, HstsConfigurationMiddleware>());
                     if (environment.IsLinuxConsumption())
                     {
-                        services.AddCors();
                         services.AddSingleton<ICorsMiddlewareFactory, CorsMiddlewareFactory>();
-                        services.TryAddEnumerable(ServiceDescriptor.Singleton<IJobHostHttpMiddleware, CorsConfigurationMiddleware>());
+                        services.TryAddEnumerable(ServiceDescriptor.Singleton<IJobHostHttpMiddleware, JobHostCorsMiddleware>());
                     }
                     services.TryAddSingleton<IScaleMetricsRepository, TableStorageScaleMetricsRepository>();
 

src/WebJobs.Script.WebHost/WebScriptHostBuilderExtension.cs

@@ -15,6 +15,7 @@
 using Microsoft.Azure.WebJobs.Script.WebHost.Middleware;
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.DependencyInjection.Extensions;
+using Microsoft.Extensions.Logging.Abstractions;
 using Microsoft.Extensions.Options;
 using Moq;
 using Xunit;
@@ -35,7 +36,7 @@ public async Task Invoke_HasCorsConfig_InvokesNext()
             var testOptions = new CorsOptions();
             testOptions.AddDefaultPolicy(testPolicy);
             var corsOptions = new OptionsWrapper<CorsOptions>(testOptions);
-            var corsFactory = new CorsMiddlewareFactory(corsOptions);
+            var corsFactory = new CorsMiddlewareFactory(corsOptions, NullLoggerFactory.Instance);
 
             bool nextInvoked = false;
             RequestDelegate next = (context) =>
@@ -45,7 +46,7 @@ public async Task Invoke_HasCorsConfig_InvokesNext()
                 return Task.CompletedTask;
             };
 
-            var middleware = new CorsConfigurationMiddleware(hostCorsOptions, corsFactory);
+            var middleware = new JobHostCorsMiddleware(hostCorsOptions, corsFactory);
 
             var httpContext = new DefaultHttpContext();
             await middleware.Invoke(httpContext, next);
@@ -83,7 +84,7 @@ public async Task Invoke_OriginAllowed_AddsExpectedHeaders()
                     services.AddTransient<IConfigureOptions<HostCorsOptions>>(factory => new TestHostCorsOptionsSetup(hostCorsOptions));
                     services.TryAddSingleton<IJobHostMiddlewarePipeline, DefaultMiddlewarePipeline>();
                     services.AddCors();
-                    services.TryAddEnumerable(ServiceDescriptor.Singleton<IJobHostHttpMiddleware, CorsConfigurationMiddleware>());
+                    services.TryAddEnumerable(ServiceDescriptor.Singleton<IJobHostHttpMiddleware, JobHostCorsMiddleware>());
                     services.AddSingleton<ICorsMiddlewareFactory, CorsMiddlewareFactory>();
                 });
 
@@ -136,7 +137,7 @@ public async Task Invoke_OriginNotAllowed_DoesNotAddHeaders()
                     services.AddTransient<IConfigureOptions<HostCorsOptions>>(factory => new TestHostCorsOptionsSetup(hostCorsOptions));
                     services.TryAddSingleton<IJobHostMiddlewarePipeline, DefaultMiddlewarePipeline>();
                     services.AddCors();
-                    services.TryAddEnumerable(ServiceDescriptor.Singleton<IJobHostHttpMiddleware, CorsConfigurationMiddleware>());
+                    services.TryAddEnumerable(ServiceDescriptor.Singleton<IJobHostHttpMiddleware, JobHostCorsMiddleware>());
                     services.AddSingleton<ICorsMiddlewareFactory, CorsMiddlewareFactory>();
                 });