Make PooledDbContextFactory public (#24712)

Closes #24137

Author: roji

src/EFCore/Extensions/EntityFrameworkServiceCollectionExtensions.cs

@@ -55,9 +55,7 @@ public static class EntityFrameworkServiceCollectionExtensions
         /// </param>
         /// <param name="contextLifetime"> The lifetime with which to register the DbContext service in the container. </param>
         /// <param name="optionsLifetime"> The lifetime with which to register the DbContextOptions service in the container. </param>
-        /// <returns>
-        ///     The same service collection so that multiple calls can be chained.
-        /// </returns>
+        /// <returns> The same service collection so that multiple calls can be chained. </returns>
         public static IServiceCollection AddDbContext<TContext>(
             this IServiceCollection serviceCollection,
             Action<DbContextOptionsBuilder>? optionsAction = null,
@@ -102,9 +100,7 @@ public static IServiceCollection AddDbContext<TContext>(
         /// </param>
         /// <param name="contextLifetime"> The lifetime with which to register the DbContext service in the container. </param>
         /// <param name="optionsLifetime"> The lifetime with which to register the DbContextOptions service in the container. </param>
-        /// <returns>
-        ///     The same service collection so that multiple calls can be chained.
-        /// </returns>
+        /// <returns> The same service collection so that multiple calls can be chained. </returns>
         public static IServiceCollection AddDbContext<TContextService, TContextImplementation>(
             this IServiceCollection serviceCollection,
             Action<DbContextOptionsBuilder>? optionsAction = null,
@@ -149,16 +145,12 @@ public static IServiceCollection AddDbContext<TContextService, TContextImplement
         ///         will not be called.
         ///     </para>
         /// </param>
-        /// <param name="poolSize">
-        ///     Sets the maximum number of instances retained by the pool.
-        /// </param>
-        /// <returns>
-        ///     The same service collection so that multiple calls can be chained.
-        /// </returns>
+        /// <param name="poolSize"> Sets the maximum number of instances retained by the pool. Defaults to 128. </param>
+        /// <returns> The same service collection so that multiple calls can be chained. </returns>
         public static IServiceCollection AddDbContextPool<TContext>(
             this IServiceCollection serviceCollection,
             Action<DbContextOptionsBuilder> optionsAction,
-            int poolSize = 128)
+            int poolSize = DbContextPool<DbContext>.DefaultPoolSize)
             where TContext : DbContext
             => AddDbContextPool<TContext, TContext>(serviceCollection, optionsAction, poolSize);
 
@@ -195,16 +187,12 @@ public static IServiceCollection AddDbContextPool<TContext>(
         ///         will not be called.
         ///     </para>
         /// </param>
-        /// <param name="poolSize">
-        ///     Sets the maximum number of instances retained by the pool.
-        /// </param>
-        /// <returns>
-        ///     The same service collection so that multiple calls can be chained.
-        /// </returns>
+        /// <param name="poolSize"> Sets the maximum number of instances retained by the pool. Defaults to 128. </param>
+        /// <returns> The same service collection so that multiple calls can be chained. </returns>
         public static IServiceCollection AddDbContextPool<TContextService, TContextImplementation>(
             this IServiceCollection serviceCollection,
             Action<DbContextOptionsBuilder> optionsAction,
-            int poolSize = 128)
+            int poolSize = DbContextPool<DbContext>.DefaultPoolSize)
             where TContextImplementation : DbContext, TContextService
             where TContextService : class
         {
@@ -253,16 +241,12 @@ public static IServiceCollection AddDbContextPool<TContextService, TContextImple
         ///         will not be called.
         ///     </para>
         /// </param>
-        /// <param name="poolSize">
-        ///     Sets the maximum number of instances retained by the pool.
-        /// </param>
-        /// <returns>
-        ///     The same service collection so that multiple calls can be chained.
-        /// </returns>
+        /// <param name="poolSize"> Sets the maximum number of instances retained by the pool. Defaults to 128. </param>
+        /// <returns> The same service collection so that multiple calls can be chained. </returns>
         public static IServiceCollection AddDbContextPool<TContext>(
             this IServiceCollection serviceCollection,
             Action<IServiceProvider, DbContextOptionsBuilder> optionsAction,
-            int poolSize = 128)
+            int poolSize = DbContextPool<DbContext>.DefaultPoolSize)
             where TContext : DbContext
             => AddDbContextPool<TContext, TContext>(serviceCollection, optionsAction, poolSize);
 
@@ -308,16 +292,12 @@ public static IServiceCollection AddDbContextPool<TContext>(
         ///         will not be called.
         ///     </para>
         /// </param>
-        /// <param name="poolSize">
-        ///     Sets the maximum number of instances retained by the pool.
-        /// </param>
-        /// <returns>
-        ///     The same service collection so that multiple calls can be chained.
-        /// </returns>
+        /// <param name="poolSize"> Sets the maximum number of instances retained by the pool. Defaults to 128. </param>
+        /// <returns> The same service collection so that multiple calls can be chained. </returns>
         public static IServiceCollection AddDbContextPool<TContextService, TContextImplementation>(
             this IServiceCollection serviceCollection,
             Action<IServiceProvider, DbContextOptionsBuilder> optionsAction,
-            int poolSize = 128)
+            int poolSize = DbContextPool<DbContext>.DefaultPoolSize)
             where TContextImplementation : DbContext, TContextService
             where TContextService : class
         {
@@ -381,9 +361,7 @@ private static void AddPoolingOptions<TContext>(
         /// <param name="serviceCollection"> The <see cref="IServiceCollection" /> to add services to. </param>
         /// <param name="contextLifetime"> The lifetime with which to register the DbContext service in the container. </param>
         /// <param name="optionsLifetime"> The lifetime with which to register the DbContextOptions service in the container. </param>
-        /// <returns>
-        ///     The same service collection so that multiple calls can be chained.
-        /// </returns>
+        /// <returns> The same service collection so that multiple calls can be chained. </returns>
         public static IServiceCollection AddDbContext<TContext>(
             this IServiceCollection serviceCollection,
             ServiceLifetime contextLifetime,
@@ -411,9 +389,7 @@ public static IServiceCollection AddDbContext<TContext>(
         /// <param name="serviceCollection"> The <see cref="IServiceCollection" /> to add services to. </param>
         /// <param name="contextLifetime"> The lifetime with which to register the DbContext service in the container. </param>
         /// <param name="optionsLifetime"> The lifetime with which to register the DbContextOptions service in the container. </param>
-        /// <returns>
-        ///     The same service collection so that multiple calls can be chained.
-        /// </returns>
+        /// <returns> The same service collection so that multiple calls can be chained. </returns>
         public static IServiceCollection AddDbContext<TContextService, TContextImplementation>(
             this IServiceCollection serviceCollection,
             ServiceLifetime contextLifetime,
@@ -470,9 +446,7 @@ public static IServiceCollection AddDbContext<TContextService, TContextImplement
         /// </param>
         /// <param name="contextLifetime"> The lifetime with which to register the DbContext service in the container. </param>
         /// <param name="optionsLifetime"> The lifetime with which to register the DbContextOptions service in the container. </param>
-        /// <returns>
-        ///     The same service collection so that multiple calls can be chained.
-        /// </returns>
+        /// <returns> The same service collection so that multiple calls can be chained. </returns>
         public static IServiceCollection AddDbContext<TContext>(
             this IServiceCollection serviceCollection,
             Action<IServiceProvider, DbContextOptionsBuilder>? optionsAction,
@@ -527,9 +501,7 @@ public static IServiceCollection AddDbContext<TContext>(
         /// </param>
         /// <param name="contextLifetime"> The lifetime with which to register the DbContext service in the container. </param>
         /// <param name="optionsLifetime"> The lifetime with which to register the DbContextOptions service in the container. </param>
-        /// <returns>
-        ///     The same service collection so that multiple calls can be chained.
-        /// </returns>
+        /// <returns> The same service collection so that multiple calls can be chained. </returns>
         public static IServiceCollection AddDbContext<TContextService, TContextImplementation>(
             this IServiceCollection serviceCollection,
             Action<IServiceProvider, DbContextOptionsBuilder>? optionsAction,
@@ -600,9 +572,7 @@ public static IServiceCollection AddDbContext<TContextService, TContextImplement
         ///     The lifetime with which to register the factory and options.
         ///     The default is <see cref="ServiceLifetime.Singleton" />
         /// </param>
-        /// <returns>
-        ///     The same service collection so that multiple calls can be chained.
-        /// </returns>
+        /// <returns> The same service collection so that multiple calls can be chained. </returns>
         public static IServiceCollection AddDbContextFactory<TContext>(
             this IServiceCollection serviceCollection,
             Action<DbContextOptionsBuilder>? optionsAction = null,
@@ -659,9 +629,7 @@ public static IServiceCollection AddDbContextFactory<TContext>(
         ///     The lifetime with which to register the factory and options.
         ///     The default is <see cref="ServiceLifetime.Singleton" />
         /// </param>
-        /// <returns>
-        ///     The same service collection so that multiple calls can be chained.
-        /// </returns>
+        /// <returns> The same service collection so that multiple calls can be chained. </returns>
         public static IServiceCollection AddDbContextFactory<TContext, TFactory>(
             this IServiceCollection serviceCollection,
             Action<DbContextOptionsBuilder>? optionsAction = null,
@@ -727,9 +695,7 @@ public static IServiceCollection AddDbContextFactory<TContext, TFactory>(
         ///     The lifetime with which to register the factory and options.
         ///     The default is <see cref="ServiceLifetime.Singleton" />
         /// </param>
-        /// <returns>
-        ///     The same service collection so that multiple calls can be chained.
-        /// </returns>
+        /// <returns> The same service collection so that multiple calls can be chained. </returns>
         public static IServiceCollection AddDbContextFactory<TContext>(
             this IServiceCollection serviceCollection,
             Action<IServiceProvider, DbContextOptionsBuilder> optionsAction,
@@ -794,9 +760,7 @@ public static IServiceCollection AddDbContextFactory<TContext>(
         ///     The lifetime with which to register the factory and options.
         ///     The default is <see cref="ServiceLifetime.Singleton" />
         /// </param>
-        /// <returns>
-        ///     The same service collection so that multiple calls can be chained.
-        /// </returns>
+        /// <returns> The same service collection so that multiple calls can be chained. </returns>
         public static IServiceCollection AddDbContextFactory<TContext, TFactory>(
             this IServiceCollection serviceCollection,
             Action<IServiceProvider, DbContextOptionsBuilder>? optionsAction,
@@ -850,16 +814,12 @@ public static IServiceCollection AddDbContextFactory<TContext, TFactory>(
         ///         will not be called.
         ///     </para>
         /// </param>
-        /// <param name="poolSize">
-        ///     Sets the maximum number of instances retained by the pool.
-        /// </param>
-        /// <returns>
-        ///     The same service collection so that multiple calls can be chained.
-        /// </returns>
+        /// <param name="poolSize"> Sets the maximum number of instances retained by the pool. Defaults to 128. </param>
+        /// <returns> The same service collection so that multiple calls can be chained. </returns>
         public static IServiceCollection AddPooledDbContextFactory<TContext>(
             this IServiceCollection serviceCollection,
             Action<DbContextOptionsBuilder> optionsAction,
-            int poolSize = 128)
+            int poolSize = DbContextPool<DbContext>.DefaultPoolSize)
             where TContext : DbContext
         {
             Check.NotNull(optionsAction, nameof(optionsAction));
@@ -898,16 +858,12 @@ public static IServiceCollection AddPooledDbContextFactory<TContext>(
         ///         will not be called.
         ///     </para>
         /// </param>
-        /// <param name="poolSize">
-        ///     Sets the maximum number of instances retained by the pool.
-        /// </param>
-        /// <returns>
-        ///     The same service collection so that multiple calls can be chained.
-        /// </returns>
+        /// <param name="poolSize"> Sets the maximum number of instances retained by the pool. Defaults to 128. </param>
+        /// <returns> The same service collection so that multiple calls can be chained. </returns>
         public static IServiceCollection AddPooledDbContextFactory<TContext>(
             this IServiceCollection serviceCollection,
             Action<IServiceProvider, DbContextOptionsBuilder> optionsAction,
-            int poolSize = 128)
+            int poolSize = DbContextPool<DbContext>.DefaultPoolSize)
             where TContext : DbContext
         {
             Check.NotNull(serviceCollection, nameof(serviceCollection));
@@ -916,7 +872,8 @@ public static IServiceCollection AddPooledDbContextFactory<TContext>(
             AddPoolingOptions<TContext>(serviceCollection, optionsAction, poolSize);
 
             serviceCollection.TryAddSingleton<IDbContextPool<TContext>, DbContextPool<TContext>>();
-            serviceCollection.TryAddSingleton<IDbContextFactory<TContext>, PooledDbContextFactory<TContext>>();
+            serviceCollection.TryAddSingleton<IDbContextFactory<TContext>>(
+                sp => new PooledDbContextFactory<TContext>(sp.GetRequiredService<IDbContextPool<TContext>>()));
 
             return serviceCollection;
         }

src/EFCore/IDbContextFactory.cs

@@ -5,8 +5,6 @@ namespace Microsoft.EntityFrameworkCore
 {
     /// <summary>
     ///     Defines a factory for creating <see cref="DbContext" /> instances.
-    ///     A service of this type is registered in the dependency injection container by the
-    ///     <see cref="M:EntityFrameworkServiceCollectionExtensions.AddDbContextPool" /> methods.
     /// </summary>
     /// <typeparam name="TContext"> The <see cref="DbContext" /> type to create. </typeparam>
     public interface IDbContextFactory<out TContext>
@@ -17,7 +15,7 @@ public interface IDbContextFactory<out TContext>
         ///         Creates a new <see cref="DbContext" /> instance.
         ///     </para>
         ///     <para>
-        ///         The caller is responsible for disposing the context; it will not be disposed by the dependency injection container.
+        ///         The caller is responsible for disposing the context; it will not be disposed by any dependency injection container.
         ///     </para>
         /// </summary>
         /// <returns> A new context instance. </returns>

src/EFCore/Infrastructure/CoreOptionsExtension.cs

@@ -488,6 +488,11 @@ public virtual void ApplyServices(IServiceCollection services)
         /// <param name="options"> The options being validated. </param>
         public virtual void Validate(IDbContextOptions options)
         {
+            if (MaxPoolSize.HasValue && MaxPoolSize <= 0)
+            {
+                throw new ArgumentOutOfRangeException(nameof(MaxPoolSize), CoreStrings.InvalidPoolSize);
+            }
+
             if (_internalServiceProvider != null)
             {
                 if (ReplacedServices != null)

src/EFCore/Infrastructure/PooledDbContextFactory.cs

@@ -0,0 +1,54 @@
+// 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.EntityFrameworkCore.Internal;
+
+namespace Microsoft.EntityFrameworkCore.Infrastructure
+{
+    /// <summary>
+    ///     <para>
+    ///         A factory returning pooled <see cref="DbContext" /> instances. Disposing the instance returned by this factory returns
+    ///         them to the internal pooling mechanism.
+    ///     </para>
+    ///     <para>
+    ///         A service of this type is registered in the dependency injection container by the
+    ///         <see cref="M:EntityFrameworkServiceCollectionExtensions.AddDbContextPool" /> methods.
+    ///     </para>
+    /// </summary>
+    public class PooledDbContextFactory<TContext> : IDbContextFactory<TContext>
+        where TContext : DbContext
+    {
+        private readonly IDbContextPool<TContext> _pool;
+
+        /// <summary>
+        ///     This is an internal API that supports the Entity Framework Core infrastructure and not subject to
+        ///     the same compatibility standards as public APIs. It may be changed or removed without notice in
+        ///     any release. You should only use it directly in your code with extreme caution and knowing that
+        ///     doing so can result in application failures when updating to a new Entity Framework Core release.
+        /// </summary>
+        [EntityFrameworkInternal]
+        public PooledDbContextFactory(IDbContextPool<TContext> pool)
+            => _pool = pool;
+
+        /// <summary>
+        ///     Initializes a new instance of the <see cref="PooledDbContextFactory{TContext}" /> class.
+        /// </summary>
+        /// <param name="options"> The options to use for contexts produced by this factory. </param>
+        /// <param name="poolSize"> Sets the maximum number of instances retained by the pool. Defaults to 128. </param>
+        public PooledDbContextFactory(DbContextOptions<TContext> options, int poolSize = DbContextPool<DbContext>.DefaultPoolSize)
+        {
+            var optionsBuilder = new DbContextOptionsBuilder<TContext>(options);
+
+            var extension = (options.FindExtension<CoreOptionsExtension>() ?? new CoreOptionsExtension())
+                .WithMaxPoolSize(poolSize);
+
+            ((IDbContextOptionsBuilderInfrastructure)optionsBuilder).AddOrUpdateExtension(extension);
+
+            _pool = new DbContextPool<TContext>(optionsBuilder.Options);
+        }
+
+        /// <inheritdoc />
+        public virtual TContext CreateDbContext()
+            => (TContext)new DbContextLease(_pool, standalone: true).Context;
+    }
+}