bff - Add local client (#1782)

bff/hosts/Blazor/WebAssembly/Hosts.Bff.Blazor.WebAssembly.Client/Pages/Weather.razor

@@ -1,5 +1,5 @@
 @page "/weather"
-@inject HttpClient Http
+@inject WeatherHttpClient Http
 
 @attribute [Authorize]
 
@@ -43,14 +43,7 @@ else
 
     protected override async Task OnInitializedAsync()
     {
-        _forecasts = await Http.GetFromJsonAsync<WeatherForecast[]>("WeatherForecast");
+        _forecasts = await Http.GetWeatherForecasts();
     }
 
-    private class WeatherForecast
-    {
-        public DateOnly Date { get; set; }
-        public int TemperatureC { get; set; }
-        public string? Summary { get; set; }
-        public int TemperatureF => 32 + (int)(TemperatureC / 0.5556);
-    }
 }

bff/hosts/Blazor/WebAssembly/Hosts.Bff.Blazor.WebAssembly.Client/Program.cs

@@ -1,4 +1,5 @@
 using Duende.Bff.Blazor.Client;
+using Hosts.Bff.Blazor.WebAssembly.Client;
 using Microsoft.AspNetCore.Components.WebAssembly.Hosting;
 
 var builder = WebAssemblyHostBuilder.CreateDefault(args);
@@ -8,11 +9,6 @@
     .AddBffBlazorClient() // Provides auth state provider that polls the /bff/user endpoint
     .AddCascadingAuthenticationState();
 
-builder.Services.AddScoped(sp =>
-    new HttpClient
-    {
-        BaseAddress = new Uri(builder.HostEnvironment.BaseAddress),
-        DefaultRequestHeaders = { {"x-csrf", "1" }}
-    });
+builder.Services.AddLocalApiHttpClient<WeatherHttpClient>();
 
-await builder.Build().RunAsync();
+await builder.Build().RunAsync();

bff/hosts/Blazor/WebAssembly/Hosts.Bff.Blazor.WebAssembly.Client/WeatherForecast.cs

@@ -0,0 +1,7 @@
+internal class WeatherForecast
+{
+    public DateOnly Date { get; set; }
+    public int TemperatureC { get; set; }
+    public string? Summary { get; set; }
+    public int TemperatureF => 32 + (int) (TemperatureC / 0.5556);
+}

bff/hosts/Blazor/WebAssembly/Hosts.Bff.Blazor.WebAssembly.Client/WeatherHttpClient.cs

@@ -0,0 +1,10 @@
+using System.Net.Http.Json;
+using System.Text.Json;
+
+namespace Hosts.Bff.Blazor.WebAssembly.Client;
+
+internal class WeatherHttpClient(HttpClient client)
+{
+    public async Task<WeatherForecast[]> GetWeatherForecasts() => await client.GetFromJsonAsync<WeatherForecast[]>("WeatherForecast")
+                                                            ?? throw new JsonException("Failed to deserialize");
+}

bff/src/Bff.Blazor.Client/ServiceCollectionExtensions.cs

@@ -56,7 +56,7 @@ private static string GetStateProviderBaseAddress(IServiceProvider sp)
         }
     }
 
-    private static string GetBaseAddress(IServiceProvider sp)
+    private static string GetRemoteBaseAddress(IServiceProvider sp)
     {
         var opt = sp.GetRequiredService<IOptions<BffBlazorOptions>>();
         if (opt.Value.RemoteApiBaseAddress != null)
@@ -65,40 +65,76 @@ private static string GetBaseAddress(IServiceProvider sp)
         }
         else
         {
-            var hostEnv = sp.GetRequiredService<IWebAssemblyHostEnvironment>();
-            return hostEnv.BaseAddress;
+            return GetLocalBaseAddress(sp);
         }
     }
 
+    private static string GetLocalBaseAddress(IServiceProvider sp)
+    {
+        var hostEnv = sp.GetRequiredService<IWebAssemblyHostEnvironment>();
+        return hostEnv.BaseAddress;
+    }
+
     private static string GetRemoteApiPath(IServiceProvider sp)
     {
         var opt = sp.GetRequiredService<IOptions<BffBlazorOptions>>();
         return opt.Value.RemoteApiPath;
     }
 
-    private static Action<IServiceProvider, HttpClient> SetBaseAddress(
+    private static Action<IServiceProvider, HttpClient> SetRemoteApiBaseAddress(
         Action<IServiceProvider, HttpClient>? configureClient)
     {
         return (sp, client) =>
         {
-            SetBaseAddress(sp, client);
+            SetRemoteApiBaseAddress(sp, client);
             configureClient?.Invoke(sp, client);
         };
     }
 
-    private static Action<IServiceProvider, HttpClient> SetBaseAddress(
+    private static Action<IServiceProvider, HttpClient> SetRemoteApiBaseAddress(
         Action<HttpClient>? configureClient)
     {
         return (sp, client) =>
         {
-            SetBaseAddress(sp, client);
+            SetRemoteApiBaseAddress(sp, client);
             configureClient?.Invoke(client);
         };
     }
 
-    private static void SetBaseAddress(IServiceProvider sp, HttpClient client)
+    private static void SetLocalApiBaseAddress(IServiceProvider sp, HttpClient client)
     {
-        var baseAddress = GetBaseAddress(sp);
+        var baseAddress = GetLocalBaseAddress(sp);
+        if (!baseAddress.EndsWith("/"))
+        {
+            baseAddress += "/";
+        }
+
+        client.BaseAddress = new Uri(baseAddress);
+
+    }
+
+    private static Action<IServiceProvider, HttpClient> SetLocalApiBaseAddress(
+        Action<HttpClient>? configureClient)
+    {
+        return (sp, client) =>
+        {
+            SetLocalApiBaseAddress(sp, client);
+            configureClient?.Invoke(client);
+        };
+    }
+
+    private static Action<IServiceProvider, HttpClient> SetLocalApiBaseAddress(
+        Action<IServiceProvider, HttpClient>? configureClient)
+    {
+        return (sp, client) =>
+        {
+            SetLocalApiBaseAddress(sp, client);
+            configureClient?.Invoke(sp, client);
+        };
+    }
+    private static void SetRemoteApiBaseAddress(IServiceProvider sp, HttpClient client)
+    {
+        var baseAddress = GetRemoteBaseAddress(sp);
         if (!baseAddress.EndsWith("/"))
         {
             baseAddress += "/";
@@ -121,6 +157,61 @@ private static void SetBaseAddress(IServiceProvider sp, HttpClient client)
         client.BaseAddress = new Uri(new Uri(baseAddress), remoteApiPath);
     }
 
+
+    /// <summary>
+    /// Adds a named <see cref="HttpClient"/> for use when invoking local APIs
+    /// and configures the client with a callback.
+    /// </summary>
+    /// <param name="services">The service collection.</param>
+    /// <param name="clientName">The name of that <see cref="HttpClient"/> to
+    /// configure. A common use case is to use the same named client in multiple
+    /// render contexts that are automatically switched between via interactive
+    /// render modes. In that case, ensure both the client and server project
+    /// define the HttpClient appropriately.</param>
+    /// <param name="configureClient">A configuration callback used to set up
+    /// the <see cref="HttpClient"/>.</param>
+    public static IHttpClientBuilder AddLocalApiHttpClient(this IServiceCollection services, string clientName,
+        Action<HttpClient> configureClient)
+    {
+        return services.AddHttpClient(clientName, SetLocalApiBaseAddress(configureClient))
+            .AddHttpMessageHandler<AntiforgeryHandler>();
+    }
+
+    /// <summary>
+    /// Adds a named <see cref="HttpClient"/> for use when invoking local APIs
+    /// and configures the client with a callback.
+    /// </summary>
+    /// <param name="services">The service collection.</param>
+    /// <param name="clientName">The name of that <see cref="HttpClient"/> to
+    /// configure. A common use case is to use the same named client in multiple
+    /// render contexts that are automatically switched between via interactive
+    /// render modes. In that case, ensure both the client and server project
+    /// define the HttpClient appropriately.</param>
+    /// <param name="configureClient">A configuration callback used to set up
+    /// the <see cref="HttpClient"/>.</param>
+    public static IHttpClientBuilder AddLocalApiHttpClient(this IServiceCollection services, string clientName,
+        Action<IServiceProvider, HttpClient>? configureClient = null)
+    {
+        return services.AddHttpClient(clientName, SetLocalApiBaseAddress(configureClient))
+            .AddHttpMessageHandler<AntiforgeryHandler>();
+    }
+
+    /// <summary>
+    /// Adds a typed <see cref="HttpClient"/> for use when invoking remote APIs
+    /// proxied through Duende.Bff and configures the client with a callback
+    /// that has access to the underlying service provider.
+    /// </summary>
+    /// <param name="services">The service collection.</param>
+    /// <param name="configureClient">A configuration callback used to set up
+    /// the <see cref="HttpClient"/>.</param>
+    public static IHttpClientBuilder AddLocalApiHttpClient<T>(this IServiceCollection services,
+        Action<IServiceProvider, HttpClient>? configureClient = null)
+        where T : class
+    {
+        return services.AddHttpClient<T>(SetLocalApiBaseAddress(configureClient))
+            .AddHttpMessageHandler<AntiforgeryHandler>();
+    }
+
     /// <summary>
     /// Adds a named <see cref="HttpClient"/> for use when invoking remote APIs
     /// proxied through Duende.Bff and configures the client with a callback.
@@ -136,7 +227,7 @@ private static void SetBaseAddress(IServiceProvider sp, HttpClient client)
     public static IHttpClientBuilder AddRemoteApiHttpClient(this IServiceCollection services, string clientName,
         Action<HttpClient> configureClient)
     {
-        return services.AddHttpClient(clientName, SetBaseAddress(configureClient))
+        return services.AddHttpClient(clientName, SetRemoteApiBaseAddress(configureClient))
             .AddHttpMessageHandler<AntiforgeryHandler>();
     }
 
@@ -156,7 +247,7 @@ public static IHttpClientBuilder AddRemoteApiHttpClient(this IServiceCollection
     public static IHttpClientBuilder AddRemoteApiHttpClient(this IServiceCollection services, string clientName,
         Action<IServiceProvider, HttpClient>? configureClient = null)
     {
-        return services.AddHttpClient(clientName, SetBaseAddress(configureClient))
+        return services.AddHttpClient(clientName, SetRemoteApiBaseAddress(configureClient))
             .AddHttpMessageHandler<AntiforgeryHandler>();
     }
 
@@ -171,7 +262,7 @@ public static IHttpClientBuilder AddRemoteApiHttpClient<T>(this IServiceCollecti
         Action<HttpClient> configureClient)
         where T : class
     {
-        return services.AddHttpClient<T>(SetBaseAddress(configureClient))
+        return services.AddHttpClient<T>(SetRemoteApiBaseAddress(configureClient))
             .AddHttpMessageHandler<AntiforgeryHandler>();
     }
 
@@ -187,7 +278,7 @@ public static IHttpClientBuilder AddRemoteApiHttpClient<T>(this IServiceCollecti
         Action<IServiceProvider, HttpClient>? configureClient = null)
         where T : class
     {
-        return services.AddHttpClient<T>(SetBaseAddress(configureClient))
+        return services.AddHttpClient<T>(SetRemoteApiBaseAddress(configureClient))
             .AddHttpMessageHandler<AntiforgeryHandler>();
     }
 }

bff/test/Bff.Blazor.Client.UnitTests/AntiforgeryHandlerTests.cs

@@ -1,4 +1,4 @@
-using NSubstitute;
+using System.Net;
 using Shouldly;
 
 namespace Duende.Bff.Blazor.Client.UnitTests;
@@ -10,7 +10,7 @@ public async Task Adds_expected_header()
     {
         var sut = new TestAntiforgeryHandler()
         {
-            InnerHandler = Substitute.For<HttpMessageHandler>()
+            InnerHandler = new NoOpHttpMessageHandler()
         };
 
         var request = new HttpRequestMessage();
@@ -27,4 +27,12 @@ public class TestAntiforgeryHandler : AntiforgeryHandler
     {
         return base.SendAsync(request, cancellationToken);
     }
+}
+
+public class NoOpHttpMessageHandler : HttpMessageHandler
+{
+    protected override Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
+    {
+        return Task.FromResult(new HttpResponseMessage(HttpStatusCode.OK));
+    }
 }