Add support for static web assets in blazor client-side (#11042)

* Add support for static web assets in blazor client-side
* Blazor serve use MSBuild data instead of heuristics to run the app
* Remove blazor-client-side app Static Web Assets when hosted in an ASP.NET Core

src/Components/Blazor/Build/src/ReferenceFromSource.props

@@ -28,7 +28,7 @@
   <PropertyGroup>
     <RunCommand>dotnet</RunCommand>
     <_BlazorCliLocation>$(MSBuildThisFileDirectory)../../DevServer/src/bin/$(Configuration)/netcoreapp3.0/blazor-devserver.dll</_BlazorCliLocation>
-    <RunArguments>exec &quot;$(_BlazorCliLocation)&quot; serve $(AdditionalRunArguments)</RunArguments>
+    <RunArguments>exec &quot;$(_BlazorCliLocation)&quot; serve &quot;$(MSBuildProjectDirectory)/$(OutputPath)$(TargetFileName)&quot; $(AdditionalRunArguments)</RunArguments>
   </PropertyGroup>
 
   <ItemGroup>

src/Components/Blazor/Build/src/targets/All.targets

@@ -29,4 +29,18 @@
       <ContentWithTargetPath Include="$(BlazorMetadataFilePath)" TargetPath="$(BlazorMetadataFileName)" CopyToOutputDirectory="PreserveNewest" />
     </ItemGroup>
   </Target>
+
+  <PropertyGroup>
+    <GetCurrentProjectStaticWebAssetsDependsOn>
+      $(GetCurrentProjectStaticWebAssetsDependsOn);
+      _ClearCurrentStaticWebAssetsForReferenceDiscovery
+    </GetCurrentProjectStaticWebAssetsDependsOn>
+  </PropertyGroup>
+
+  <Target Name="_ClearCurrentStaticWebAssetsForReferenceDiscovery">
+    <ItemGroup>
+      <StaticWebAsset Remove="@(StaticWebAsset)" Condition="'%(SourceType)' == ''" />
+    </ItemGroup>
+  </Target>
+
 </Project>

src/Components/Blazor/DevServer/src/Commands/ServeCommand.cs

@@ -1,6 +1,9 @@
 // Copyright (c) .NET Foundation. All rights reserved.
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
+using System;
+using System.IO;
+using System.Runtime.Versioning;
 using Microsoft.AspNetCore.Hosting;
 using Microsoft.Extensions.CommandLineUtils;
 
@@ -20,11 +23,28 @@ namespace Microsoft.AspNetCore.Blazor.DevServer.Commands
 
             HelpOption("-?|-h|--help");
 
+            ApplicationPath = new CommandArgument()
+            {
+                Description = "Path to the client application dll",
+                MultipleValues = false,
+                Name = "<PATH>",
+                ShowInHelpText = true
+            };
+            Arguments.Add(ApplicationPath);
+
             OnExecute(Execute);
         }
 
+        public CommandArgument ApplicationPath { get; private set; }
+
         private int Execute()
         {
+            if (string.IsNullOrWhiteSpace(ApplicationPath.Value))
+            {
+                throw new InvalidOperationException($"Invalid value for parameter '{nameof(ApplicationPath)}'. Value supplied: '{ApplicationPath.Value}'");
+            }
+
+            Server.Startup.ApplicationAssembly = ApplicationPath.Value;
             Server.Program.BuildWebHost(RemainingArguments.ToArray()).Run();
             return 0;
         }

src/Components/Blazor/DevServer/src/Server/Startup.cs

@@ -1,22 +1,24 @@
 // Copyright (c) .NET Foundation. All rights reserved.
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
-using Microsoft.AspNetCore.Components.Server;
+using System;
+using System.IO;
+using System.Linq;
+using System.Net.Mime;
 using Microsoft.AspNetCore.Builder;
+using Microsoft.AspNetCore.Components.Server;
 using Microsoft.AspNetCore.Hosting;
 using Microsoft.AspNetCore.Http;
 using Microsoft.AspNetCore.ResponseCompression;
 using Microsoft.Extensions.Configuration;
 using Microsoft.Extensions.DependencyInjection;
-using System;
-using System.IO;
-using System.Linq;
-using System.Net.Mime;
 
 namespace Microsoft.AspNetCore.Blazor.DevServer.Server
 {
     internal class Startup
     {
+        public static string ApplicationAssembly { get; set; }
+
         public void ConfigureServices(IServiceCollection services)
         {
             services.AddRouting();
@@ -33,22 +35,36 @@ namespace Microsoft.AspNetCore.Blazor.DevServer.Server
 
         public void Configure(IApplicationBuilder app, IWebHostEnvironment environment, IConfiguration configuration)
         {
+            var applicationAssemblyFullPath = ResolveApplicationAssemblyFullPath(environment);
+
             app.UseDeveloperExceptionPage();
             app.UseResponseCompression();
             EnableConfiguredPathbase(app, configuration);
 
             app.UseBlazorDebugging();
 
-            app.UseClientSideBlazorFiles(FindClientAssemblyPath(environment));
+            app.UseStaticFiles();
+            app.UseClientSideBlazorFiles(applicationAssemblyFullPath);
 
             app.UseRouting();
 
             app.UseEndpoints(endpoints =>
             {
-                endpoints.MapFallbackToClientSideBlazor(FindClientAssemblyPath(environment), "index.html");
+                endpoints.MapFallbackToClientSideBlazor(applicationAssemblyFullPath, "index.html");
             });
         }
 
+        private static string ResolveApplicationAssemblyFullPath(IWebHostEnvironment environment)
+        {
+            var applicationAssemblyFullPath = Path.Combine(environment.ContentRootPath, ApplicationAssembly);
+            if (!File.Exists(applicationAssemblyFullPath))
+            {
+                throw new InvalidOperationException($"Application assembly not found at {applicationAssemblyFullPath}.");
+            }
+
+            return applicationAssemblyFullPath;
+        }
+
         private static void EnableConfiguredPathbase(IApplicationBuilder app, IConfiguration configuration)
         {
             var pathBase = configuration.GetValue<string>("pathbase");
@@ -73,53 +89,5 @@ namespace Microsoft.AspNetCore.Blazor.DevServer.Server
                 });
             }
         }
-
-        private static string FindClientAssemblyPath(IWebHostEnvironment environment)
-        {
-            var contentRoot = environment.ContentRootPath;
-            var binDir = FindClientBinDir(contentRoot);
-            var appName = Path.GetFileName(contentRoot); // TODO: Allow for the possibility that the assembly name has been overridden
-            var assemblyPath = Path.Combine(binDir, $"{appName}.dll");
-            if (!File.Exists(assemblyPath))
-            {
-                throw new FileNotFoundException($"Could not locate application assembly at expected location {assemblyPath}");
-            }
-
-            return assemblyPath;
-        }
-
-        private static string FindClientBinDir(string clientAppSourceRoot)
-        {
-            // As a temporary workaround for https://github.com/aspnet/Blazor/issues/261,
-            // disallow the scenario where there is both a Debug *and* a Release dir.
-            // Only allow there to be one, and that's the one we pick.
-            var debugDirPath = Path.Combine(clientAppSourceRoot, "bin", "Debug");
-            var releaseDirPath = Path.Combine(clientAppSourceRoot, "bin", "Release");
-            var debugDirExists = Directory.Exists(debugDirPath);
-            var releaseDirExists = Directory.Exists(releaseDirPath);
-            if (debugDirExists && releaseDirExists)
-            {
-                throw new InvalidOperationException($"Cannot identify unique bin directory for Blazor app. " +
-                    $"Found both '{debugDirPath}' and '{releaseDirPath}'. Ensure that only one is present on " +
-                    $"disk. This is a temporary limitation (see https://github.com/aspnet/Blazor/issues/261).");
-            }
-
-            if (!(debugDirExists || releaseDirExists))
-            {
-                throw new InvalidOperationException($"Cannot find bin directory for Blazor app. " +
-                    $"Neither '{debugDirPath}' nor '{releaseDirPath}' exists on disk. Make sure the project has been built.");
-            }
-
-            var binDir = debugDirExists ? debugDirPath : releaseDirPath;
-
-            var subdirectories = Directory.GetDirectories(binDir);
-            if (subdirectories.Length != 1)
-            {
-                throw new InvalidOperationException($"Could not locate bin directory for Blazor app. " +
-                    $"Expected to find exactly 1 subdirectory in '{binDir}', but found {subdirectories.Length}.");
-            }
-
-            return Path.Combine(binDir, subdirectories[0]);
-        }
     }
 }

src/Components/Blazor/DevServer/src/build/Microsoft.AspNetCore.Blazor.DevServer.props

@@ -1,7 +1,7 @@
-<Project>
+<Project>
   <PropertyGroup>
     <_BlazorDevServerDll>$(MSBuildThisFileDirectory)../tools/blazor-devserver.dll</_BlazorDevServerDll>
     <RunCommand>dotnet</RunCommand>
-    <RunArguments>&quot;$(_BlazorDevServerDll)&quot; serve</RunArguments>
+    <RunArguments>&quot;$(_BlazorDevServerDll)&quot; serve &quot;$(MSBuildProjectDirectory)/$(OutputPath)$(TargetFileName)&quot;</RunArguments>
   </PropertyGroup>
 </Project>

src/Components/Blazor/Templates/src/content/BlazorHosted-CSharp/BlazorHosted-CSharp.Server/Startup.cs

@@ -33,6 +33,7 @@ namespace BlazorHosted_CSharp.Server
                 app.UseBlazorDebugging();
             }
 
+            app.UseStaticFiles();
             app.UseClientSideBlazorFiles<Client.Startup>();
 
             app.UseRouting();

src/Components/Blazor/testassets/HostedInAspNet.Client/HostedInAspNet.Client.csproj

@@ -11,4 +11,17 @@
     <Reference Include="Microsoft.AspNetCore.Blazor" />
   </ItemGroup>
 
+  <PropertyGroup>
+    <GetCurrentProjectStaticWebAssetsDependsOn>
+      $(GetCurrentProjectStaticWebAssetsDependsOn);
+      _ClearCurrentStaticWebAssetsForReferenceDiscovery
+    </GetCurrentProjectStaticWebAssetsDependsOn>
+  </PropertyGroup>
+
+  <Target Name="_ClearCurrentStaticWebAssetsForReferenceDiscovery">
+    <ItemGroup>
+      <StaticWebAsset Remove="@(StaticWebAsset)" Condition="'%(SourceType)' == ''" />
+    </ItemGroup>
+  </Target>
+
 </Project>

src/Components/Browser.JS/src/Boot.Server.ts

@@ -45,11 +45,6 @@ async function boot(userOptions?: Partial<BlazorOptions>): Promise<void> {
   const circuitHandlers: CircuitHandler[] = [new AutoReconnectCircuitHandler(logger)];
   window['Blazor'].circuitHandlers = circuitHandlers;
 
-  // In the background, start loading the boot config and any embedded resources
-  const embeddedResourcesPromise = fetchBootConfigAsync().then(bootConfig => {
-    return loadEmbeddedResourcesAsync(bootConfig);
-  });
-
   // pass options.configureSignalR to configure the signalR.HubConnectionBuilder
   const initialConnection = await initializeConnection(options, circuitHandlers, logger);
 
@@ -62,9 +57,6 @@ async function boot(userOptions?: Partial<BlazorOptions>): Promise<void> {
     }
   }
 
-  // Ensure any embedded resources have been loaded before starting the app
-  await embeddedResourcesPromise;
-
   const circuit = await startCircuit(initialConnection);
 
   if (!circuit) {

src/Components/Server/src/DependencyInjection/ConfigureStaticFilesOptions.cs

@@ -60,56 +60,7 @@ namespace Microsoft.AspNetCore.Components.Server
             // Add our provider
             var provider = new ManifestEmbeddedFileProvider(typeof(ConfigureStaticFilesOptions).Assembly);
 
-            options.FileProvider = new CompositeFileProvider(provider, new ContentReferencesFileProvider(), options.FileProvider);
+            options.FileProvider = new CompositeFileProvider(provider, options.FileProvider);
-        }
-
-        private class ContentReferencesFileProvider : IFileProvider
-        {
-            byte[] _data = Encoding.UTF8.GetBytes(@"{ ""cssReferences"": [], ""jsReferences"": [] }");
-
-            public IDirectoryContents GetDirectoryContents(string subpath)
-            {
-                return new NotFoundDirectoryContents();
-            }
-
-            public IFileInfo GetFileInfo(string subpath)
-            {
-                if (subpath.Equals("/_framework/blazor.boot.json", StringComparison.OrdinalIgnoreCase))
-                {
-                    return new MemoryFileInfo(_data);
-                }
-
-                return new NotFoundFileInfo(subpath);
-            }
-
-            public IChangeToken Watch(string filter) => NullChangeToken.Singleton;
-
-            private class MemoryFileInfo : IFileInfo
-            {
-                private readonly byte[] _data;
-
-                public MemoryFileInfo(byte[] data)
-                {
-                    _data = data;
-                }
-
-                public bool Exists => true;
-
-                public long Length => _data.Length;
-
-                public string PhysicalPath => null;
-
-                public string Name => "blazor.boot.json";
-
-                public DateTimeOffset LastModified => DateTimeOffset.FromUnixTimeSeconds(0);
-
-                public bool IsDirectory => false;
-
-                public Stream CreateReadStream()
-                {
-                    return new MemoryStream(_data, writable: false);
-                }
-            }
         }
     }
 }