feat: add WithDelegateStrategy<TContext, TTenantInfo> (#932)

Author: AndrewTriesToCode

docs/ConfigurationAndUsage.md

@@ -58,7 +58,8 @@ in the order registered. See [MultiTenant Strategies](Strategies) for more infor
 - `WithBasePathStrategy`
 - `WithClaimStrategy`
 - `WithDelegateStrategy`
-- `WithHeaderStrateg`y
+- `WithDelegateStrategy<TContext, TTenantInfo>`
+- `WithHeaderStrategy`
 - `WithHostStrategy`
 - `WithRouteStrategy`
 - `WithSessionStrategy`

docs/Strategies.md

@@ -65,7 +65,9 @@ This strategy is good to use for testing or simple logic. This strategy is confi
 order configured.
 
 Configure by calling `WithDelegateStrategy` after `AddMultiTenant<TTenantInfo>` A `Func<object, Task<string?>>`is passed
-in which will be used with each request to resolve the tenant. A lambda or async lambda can be used as the parameter:
+in which will be used with each request to resolve the tenant. A lambda or async lambda can be used as the parameter.
+Alternatively, `WithDelegateStrategy<TContext, TTenantInfo>` accepts a typed context parameter. Tenant resolution will
+ignore this strategy if the context is not of the correct type:
 
 ```csharp
 // use async logic to get the tenant identifier
@@ -75,15 +77,11 @@ builder.Services.AddMultiTenant<TenantInfo>()
         string? tenantIdentifier = await DoSomethingAsync(context);
         return tenantIdentifier
     })...
-    
- // or do it without async
+
+// or register with a typed lambda, HttpContext in this case
 builder.Services.AddMultiTenant<TenantInfo>()
-    .WithDelegateStrategy(context =>
-    {
-        var httpContext = context as HttpContext;
-        if (httpContext == null)
-            return null;
-        
+    .WithDelegateStrategy<HttpContext, TenantInfo>(httpContext =>
+    {      
         httpContext.Request.Query.TryGetValue("tenant", out StringValues tenantIdentifier);
 
         if (tenantIdentifier is null)

src/Finbuckle.MultiTenant/DependencyInjection/MultiTenantBuilderExtensions.cs

@@ -22,8 +22,10 @@ namespace Finbuckle.MultiTenant;
 public static class MultiTenantBuilderExtensions
 {
     /// <summary>
-    /// Adds a DistributedCacheStore to the application.
+    /// Adds a DistributedCacheStore to the application with maximum sliding expiration.
     /// </summary>
+    /// <typeparam name="TTenantInfo">The ITenantInfo implementation type.</typeparam>
+    /// <returns>The <see cref="MultiTenantBuilder&lt;TTenantInfo&gt;"/> so that additional calls can be chained.</returns>
     public static MultiTenantBuilder<TTenantInfo> WithDistributedCacheStore<TTenantInfo>(this MultiTenantBuilder<TTenantInfo> builder)
         where TTenantInfo : class, ITenantInfo, new()
         => builder.WithDistributedCacheStore(TimeSpan.MaxValue);
@@ -32,8 +34,10 @@ public static MultiTenantBuilder<TTenantInfo> WithDistributedCacheStore<TTenantI
     /// <summary>
     /// Adds a DistributedCacheStore to the application.
     /// </summary>
+    /// <typeparam name="TTenantInfo">The ITenantInfo implementation type.</typeparam>
     /// <param name="builder">The builder instance.</param>
     /// <param name="slidingExpiration">The timespan for a cache entry's sliding expiration.</param>
+    /// <returns>The <see cref="MultiTenantBuilder&lt;TTenantInfo&gt;"/> so that additional calls can be chained.</returns>
     public static MultiTenantBuilder<TTenantInfo> WithDistributedCacheStore<TTenantInfo>(this MultiTenantBuilder<TTenantInfo> builder, TimeSpan? slidingExpiration)
         where TTenantInfo : class, ITenantInfo, new()
     {
@@ -45,18 +49,22 @@ public static MultiTenantBuilder<TTenantInfo> WithDistributedCacheStore<TTenantI
     /// <summary>
     /// Adds a HttpRemoteStore to the application.
     /// </summary>
+    /// <typeparam name="TTenantInfo">The ITenantInfo implementation type.</typeparam>
     /// <param name="builder">The builder instance.</param>
     /// <param name="endpointTemplate">The endpoint URI template.</param>
+    /// <returns>The <see cref="MultiTenantBuilder&lt;TTenantInfo&gt;"/> so that additional calls can be chained.</returns>
     public static MultiTenantBuilder<TTenantInfo> WithHttpRemoteStore<TTenantInfo>(this MultiTenantBuilder<TTenantInfo> builder, string endpointTemplate)
         where TTenantInfo : class, ITenantInfo, new()
         => builder.WithHttpRemoteStore(endpointTemplate, null);
 
     /// <summary>
     /// Adds a HttpRemoteStore to the application.
     /// </summary>
+    /// <typeparam name="TTenantInfo">The ITenantInfo implementation type.</typeparam>
     /// <param name="builder">The builder instance.</param>
     /// <param name="endpointTemplate">The endpoint URI template.</param>
     /// <param name="clientConfig">An action to configure the underlying HttpClient.</param>
+    /// <returns>The <see cref="MultiTenantBuilder&lt;TTenantInfo&gt;"/> so that additional calls can be chained.</returns>
     public static MultiTenantBuilder<TTenantInfo> WithHttpRemoteStore<TTenantInfo>(this MultiTenantBuilder<TTenantInfo> builder,
         string endpointTemplate,
         Action<IHttpClientBuilder>? clientConfig) where TTenantInfo : class, ITenantInfo, new()
@@ -72,17 +80,21 @@ public static MultiTenantBuilder<TTenantInfo> WithHttpRemoteStore<TTenantInfo>(t
     /// <summary>
     /// Adds a ConfigurationStore to the application. Uses the default IConfiguration and section "Finbuckle:MultiTenant:Stores:ConfigurationStore".
     /// </summary>
+    /// <typeparam name="TTenantInfo">The ITenantInfo implementation type.</typeparam>
     /// <param name="builder">The builder instance.</param>
+    /// <returns>The <see cref="MultiTenantBuilder&lt;TTenantInfo&gt;"/> so that additional calls can be chained.</returns>
     public static MultiTenantBuilder<TTenantInfo> WithConfigurationStore<TTenantInfo>(this MultiTenantBuilder<TTenantInfo> builder)
         where TTenantInfo : class, ITenantInfo, new()
         => builder.WithStore<ConfigurationStore<TTenantInfo>>(ServiceLifetime.Singleton);
 
     /// <summary>
     /// Adds a ConfigurationStore to the application.
     /// </summary>
+    /// <typeparam name="TTenantInfo">The ITenantInfo implementation type.</typeparam>
     /// <param name="builder">The builder instance.</param>
     /// <param name="configuration">The IConfiguration to load the section from.</param>
     /// <param name="sectionName">The configuration section to load.</param>
+    /// <returns>The <see cref="MultiTenantBuilder&lt;TTenantInfo&gt;"/> so that additional calls can be chained.</returns>
     public static MultiTenantBuilder<TTenantInfo> WithConfigurationStore<TTenantInfo>(this MultiTenantBuilder<TTenantInfo> builder,
         IConfiguration configuration,
         string sectionName)
@@ -92,17 +104,20 @@ public static MultiTenantBuilder<TTenantInfo> WithConfigurationStore<TTenantInfo
     /// <summary>
     /// Adds an empty InMemoryStore to the application.
     /// </summary>
+    /// <typeparam name="TTenantInfo">The ITenantInfo implementation type.</typeparam>
     /// <param name="builder">The builder instance.</param>
+    /// <returns>The <see cref="MultiTenantBuilder&lt;TTenantInfo&gt;"/> so that additional calls can be chained.</returns>
     public static MultiTenantBuilder<TTenantInfo> WithInMemoryStore<TTenantInfo>(this MultiTenantBuilder<TTenantInfo> builder)
         where TTenantInfo : class, ITenantInfo, new()
-    // ReSharper disable once RedundantTypeArgumentsOfMethod
-        => builder.WithInMemoryStore<TTenantInfo>(_ => {});
+        => builder.WithInMemoryStore(_ => {});
 
     /// <summary>
     /// Adds and configures InMemoryStore to the application using the provided action.
     /// </summary>
+    /// <typeparam name="TTenantInfo">The ITenantInfo implementation type.</typeparam>
     /// <param name="builder">The builder instance.</param>
     /// <param name="config">An action for configuring the store.</param>
+    /// <returns>The <see cref="MultiTenantBuilder&lt;TTenantInfo&gt;"/> so that additional calls can be chained.</returns>
     public static MultiTenantBuilder<TTenantInfo> WithInMemoryStore<TTenantInfo>(this MultiTenantBuilder<TTenantInfo> builder,
         Action<InMemoryStoreOptions<TTenantInfo>> config)
         where TTenantInfo : class, ITenantInfo, new()
@@ -121,16 +136,20 @@ public static MultiTenantBuilder<TTenantInfo> WithInMemoryStore<TTenantInfo>(thi
     /// <summary>
     /// Adds an EchoStore to the application.
     /// </summary>
+    /// <typeparam name="TTenantInfo">The ITenantInfo implementation type.</typeparam>
     /// <param name="builder">The builder instance.</param>
+    /// <returns>The <see cref="MultiTenantBuilder&lt;TTenantInfo&gt;"/> so that additional calls can be chained.</returns>
     public static MultiTenantBuilder<TTenantInfo> WithEchoStore<TTenantInfo>(this MultiTenantBuilder<TTenantInfo> builder)
         where TTenantInfo : class, ITenantInfo, new()
         => builder.WithStore<EchoStore<TTenantInfo>>(ServiceLifetime.Singleton);
 
     /// <summary>
     /// Adds and configures a StaticStrategy to the application.
     /// </summary>
+    /// <typeparam name="TTenantInfo">The ITenantInfo implementation type.</typeparam>
     /// <param name="builder">The builder instance.</param>
     /// <param name="identifier">The tenant identifier to use for all tenant resolution.</param>
+    /// <returns>The <see cref="MultiTenantBuilder&lt;TTenantInfo&gt;"/> so that additional calls can be chained.</returns>
     public static MultiTenantBuilder<TTenantInfo> WithStaticStrategy<TTenantInfo>(this MultiTenantBuilder<TTenantInfo> builder,
         string identifier)
         where TTenantInfo : class, ITenantInfo, new()
@@ -146,8 +165,10 @@ public static MultiTenantBuilder<TTenantInfo> WithStaticStrategy<TTenantInfo>(th
     /// <summary>
     /// Adds and configures a DelegateStrategy to the application.
     /// </summary>
+    /// <typeparam name="TTenantInfo">The ITenantInfo implementation type.</typeparam>
     /// <param name="builder">The builder instance.</param>
     /// <param name="doStrategy">The delegate implementing the strategy.</param>
+    /// <returns>The <see cref="MultiTenantBuilder&lt;TTenantInfo&gt;"/> so that additional calls can be chained.</returns>
     public static MultiTenantBuilder<TTenantInfo> WithDelegateStrategy<TTenantInfo>(this MultiTenantBuilder<TTenantInfo> builder,
         Func<object, Task<string?>> doStrategy)
         where TTenantInfo : class, ITenantInfo, new()
@@ -159,4 +180,31 @@ public static MultiTenantBuilder<TTenantInfo> WithDelegateStrategy<TTenantInfo>(
 
         return builder.WithStrategy<DelegateStrategy>(ServiceLifetime.Singleton, new object[] { doStrategy });
     }
+    
+    /// <summary>
+    /// Adds and configures a typed DelegateStrategy&lt;TContext&gt; to the application.
+    /// </summary>
+    /// <typeparam name="TContext">The strategy context type.</typeparam>
+    /// <typeparam name="TTenantInfo">The ITenantInfo implementation type.</typeparam>
+    /// <param name="builder"></param>
+    /// <param name="doStrategy"></param>
+    /// <returns>The <see cref="MultiTenantBuilder&lt;TTenantInfo&gt;"/> so that additional calls can be chained.</returns>
+    public static MultiTenantBuilder<TTenantInfo> WithDelegateStrategy<TContext, TTenantInfo>(this MultiTenantBuilder<TTenantInfo> builder,
+        Func<TContext, Task<string?>> doStrategy)
+        where TTenantInfo : class, ITenantInfo, new()
+    {
+        ArgumentNullException.ThrowIfNull(doStrategy, nameof(doStrategy));
+
+        Func<object, Task<string?>> wrapStrategy = context =>
+        {
+            if (context.GetType() == typeof(TContext))
+            {
+                return doStrategy((TContext)context);
+            }
+
+            return Task.FromResult<string?>(null);
+        };
+
+        return builder.WithDelegateStrategy(wrapStrategy);
+    }
 }

src/Finbuckle.MultiTenant/DependencyInjection/OptionsBuilderExtensions.cs

@@ -11,13 +11,15 @@
 // ReSharper disable once CheckNamespace
 namespace Finbuckle.MultiTenant;
 
+// TODO XML comments
 public static class OptionsBuilderExtensions
 {
     public static OptionsBuilder<TOptions> ConfigurePerTenant<TOptions, TTenantInfo>(
         this OptionsBuilder<TOptions> optionsBuilder, Action<TOptions, TTenantInfo> configureOptions)
         where TOptions : class
         where TTenantInfo : class, ITenantInfo, new()
     {
+        // TODO use ThrowNull here?
         if (configureOptions == null) throw new ArgumentNullException(nameof(configureOptions));
 
         FinbuckleServiceCollectionExtensions.ConfigurePerTenantReqs<TOptions>(optionsBuilder.Services);

src/Finbuckle.MultiTenant/DependencyInjection/ServiceCollectionExtensions.cs

@@ -21,6 +21,7 @@ public static class FinbuckleServiceCollectionExtensions
     /// <summary>
     /// Configure Finbuckle.MultiTenant services for the application.
     /// </summary>
+    /// <typeparam name="TTenantInfo">The ITenantInfo implementation type.</typeparam>
     /// <param name="services">The <c>IServiceCollection</c> instance the extension method applies to.</param>
     /// <param name="config">An action to configure the MultiTenantOptions instance.</param>
     /// <returns>A new instance of MultiTenantBuilder.</returns>

src/Finbuckle.MultiTenant/MultiTenantBuilder.cs

@@ -6,6 +6,8 @@
 
 namespace Finbuckle.MultiTenant;
 
+// TODO: factor TTenantInfo into WithStore only
+
 /// <summary>
 /// Builder class for Finbuckle.MultiTenant configuration.
 /// </summary>

test/Finbuckle.MultiTenant.Test/DependencyInjection/MultiTenantBuilderExtensionsShould.cs

@@ -189,6 +189,31 @@ public void AddDelegateStrategy()
         var strategy = sp.GetRequiredService<IMultiTenantStrategy>();
         Assert.IsType<DelegateStrategy>(strategy);
     }
+    
+    [Fact]
+    public void AddTypedDelegateStrategy()
+    {
+        var services = new ServiceCollection();
+        var builder = new MultiTenantBuilder<TenantInfo>(services);
+        builder.WithDelegateStrategy<int, TenantInfo>(context => Task.FromResult(context.ToString())!);
+        var sp = services.BuildServiceProvider();
+
+        var strategy = sp.GetRequiredService<IMultiTenantStrategy>();
+        Assert.IsType<DelegateStrategy>(strategy);
+    }
+    
+    [Fact]
+    public async Task ReturnNullForWrongTypeSendToTypedDelegateStrategy()
+    {
+        var services = new ServiceCollection();
+        var builder = new MultiTenantBuilder<TenantInfo>(services);
+        builder.WithDelegateStrategy<int, TenantInfo>(context => Task.FromResult("Shouldn't ever get here")!);
+        var sp = services.BuildServiceProvider();
+
+        var strategy = sp.GetRequiredService<IMultiTenantStrategy>();
+        var identifier = await strategy.GetIdentifierAsync(new object());
+        Assert.Null(identifier);
+    }
 
     [Fact]
     public void AddStaticStrategy()