aspnetcore/src/Microsoft.AspNet.Http/Extensions/MapWhenExtensions.cs

79 lines
3.1 KiB
C#

// Copyright (c) Microsoft Open Technologies, Inc.
// All Rights Reserved
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// THIS CODE IS PROVIDED *AS IS* BASIS, WITHOUT WARRANTIES OR
// CONDITIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED, INCLUDING
// WITHOUT LIMITATION ANY IMPLIED WARRANTIES OR CONDITIONS OF
// TITLE, FITNESS FOR A PARTICULAR PURPOSE, MERCHANTABLITY OR
// NON-INFRINGEMENT.
// See the Apache 2 License for the specific language governing
// permissions and limitations under the License.
using System;
using System.Threading.Tasks;
using Microsoft.AspNet.Http;
using Microsoft.AspNet.Builder.Extensions;
namespace Microsoft.AspNet.Builder
{
using Predicate = Func<HttpContext, bool>;
using PredicateAsync = Func<HttpContext, Task<bool>>;
/// <summary>
/// Extension methods for the MapWhenMiddleware
/// </summary>
public static class MapWhenExtensions
{
/// <summary>
/// Branches the request pipeline based on the result of the given predicate.
/// </summary>
/// <param name="app"></param>
/// <param name="predicate">Invoked with the request environment to determine if the branch should be taken</param>
/// <param name="configuration">Configures a branch to take</param>
/// <returns></returns>
public static IBuilder MapWhen([NotNull] this IBuilder app, [NotNull] Predicate predicate, [NotNull] Action<IBuilder> configuration)
{
// create branch
IBuilder branchBuilder = app.New();
configuration(branchBuilder);
var branch = branchBuilder.Build();
// put middleware in pipeline
var options = new MapWhenOptions
{
Predicate = predicate,
Branch = branch,
};
return app.Use(next => new MapWhenMiddleware(next, options).Invoke);
}
/// <summary>
/// Branches the request pipeline based on the async result of the given predicate.
/// </summary>
/// <param name="app"></param>
/// <param name="predicate">Invoked asynchronously with the request environment to determine if the branch should be taken</param>
/// <param name="configuration">Configures a branch to take</param>
/// <returns></returns>
public static IBuilder MapWhenAsync([NotNull] this IBuilder app, [NotNull] PredicateAsync predicate, [NotNull] Action<IBuilder> configuration)
{
// create branch
IBuilder branchBuilder = app.New();
configuration(branchBuilder);
var branch = branchBuilder.Build();
// put middleware in pipeline
var options = new MapWhenOptions
{
PredicateAsync = predicate,
Branch = branch,
};
return app.Use(next => new MapWhenMiddleware(next, options).Invoke);
}
}
}