aspnetcore/src/Microsoft.AspNet.Mvc.Core/ActionConstraints/HttpMethodConstraint.cs

81 lines
2.5 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 System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Linq;
using Microsoft.Framework.Internal;
using Microsoft.Framework.Primitives;
namespace Microsoft.AspNet.Mvc.ActionConstraints
{
public class HttpMethodConstraint : IActionConstraint
{
public static readonly int HttpMethodConstraintOrder = 100;
private readonly IReadOnlyList<string> _methods;
private readonly string OriginHeader = "Origin";
private readonly string AccessControlRequestMethod = "Access-Control-Request-Method";
private readonly string PreflightHttpMethod = "OPTIONS";
// Empty collection means any method will be accepted.
public HttpMethodConstraint([NotNull] IEnumerable<string> httpMethods)
{
var methods = new List<string>();
foreach (var method in httpMethods)
{
if (string.IsNullOrEmpty(method))
{
throw new ArgumentException("httpMethod cannot be null or empty");
}
methods.Add(method);
}
_methods = new ReadOnlyCollection<string>(methods);
}
public IEnumerable<string> HttpMethods
{
get
{
return _methods;
}
}
public int Order
{
get { return HttpMethodConstraintOrder; }
}
public bool Accept([NotNull] ActionConstraintContext context)
{
if (_methods.Count == 0)
{
return true;
}
var request = context.RouteContext.HttpContext.Request;
var method = request.Method;
if (request.Headers.ContainsKey(OriginHeader))
{
// Update the http method if it is preflight request.
var accessControlRequestMethod = request.Headers[AccessControlRequestMethod];
if (string.Equals(
request.Method,
PreflightHttpMethod,
StringComparison.Ordinal) &&
!StringValues.IsNullOrEmpty(accessControlRequestMethod))
{
method = accessControlRequestMethod;
}
}
return (HttpMethods.Any(m => m.Equals(method, StringComparison.Ordinal)));
}
}
}