aspnetcore/src/Microsoft.AspNetCore.Mvc.Core/Internal/DefaultActionConstraintProv...

64 lines
2.1 KiB
C#

// 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 Microsoft.AspNetCore.Mvc.ActionConstraints;
namespace Microsoft.AspNetCore.Mvc.Internal
{
/// <summary>
/// A default implementation of <see cref="IActionConstraintProvider"/>.
/// </summary>
/// <remarks>
/// This provider is able to provide an <see cref="IActionConstraint"/> instance when the
/// <see cref="IActionConstraintMetadata"/> implements <see cref="IActionConstraint"/> or
/// <see cref="IActionConstraintFactory"/>/
/// </remarks>
public class DefaultActionConstraintProvider : IActionConstraintProvider
{
/// <inheritdoc />
public int Order => -1000;
/// <inheritdoc />
public void OnProvidersExecuting(ActionConstraintProviderContext context)
{
if (context == null)
{
throw new ArgumentNullException(nameof(context));
}
for (var i = 0; i < context.Results.Count; i++)
{
ProvideConstraint(context.Results[i], context.HttpContext.RequestServices);
}
}
/// <inheritdoc />
public void OnProvidersExecuted(ActionConstraintProviderContext context)
{
}
private void ProvideConstraint(ActionConstraintItem item, IServiceProvider services)
{
// Don't overwrite anything that was done by a previous provider.
if (item.Constraint != null)
{
return;
}
if (item.Metadata is IActionConstraint constraint)
{
item.Constraint = constraint;
item.IsReusable = true;
return;
}
if (item.Metadata is IActionConstraintFactory factory)
{
item.Constraint = factory.CreateInstance(services);
item.IsReusable = factory.IsReusable;
return;
}
}
}
}