ASP.NET Core 中文文档 第三章 原理（16）.NET开放Web接口（OWIN）

在 ASP.NET 管道中运行 OWIN 中间件

Microsoft.AspNetCore.Owin

"dependencies": {
"Microsoft.AspNetCore.Server.IISIntegration": "1.0.0",
"Microsoft.AspNetCore.Server.Kestrel": "1.0.0",
"Microsoft.AspNetCore.Owin": "1.0.0"                    //手动高亮
},

Func<IDictionary<string, object>, Task>

owin.ResponseBody

public Task OwinHello(IDictionary<string, object> environment)
{
string responseText = "Hello World via OWIN";
byte[] responseBytes = Encoding.UTF8.GetBytes(responseText);

// OWIN Environment Keys: http://owin.org/spec/spec/owin-1.0.0.html var responseStream = (Stream)environment["owin.ResponseBody"];
var responseHeaders = (IDictionary<string, string[]>)environment["owin.ResponseHeaders"];

responseHeaders["Content-Length"] = new string[] { responseBytes.Length.ToString(CultureInfo.InvariantCulture) };
responseHeaders["Content-Type"] = new string[] { "text/plain" };

return responseStream.WriteAsync(responseBytes, 0, responseBytes.Length);
}

IDictionary<string, object>

Task

UseOwin

OwinHello

public void Configure(IApplicationBuilder app)
{
app.UseOwin(pipeline =>
{
pipeline(next => OwinHello);
});
}

UseOwin

app.UseOwin(pipeline =>
{
pipeline(next =>
{
// do something before
return OwinHello;
// do something after
});
});

在基于 OWIN 的服务器上宿主 ASP.NET

Nowin

using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Hosting.Server;
using Microsoft.AspNetCore.Hosting.Server.Features;
using Microsoft.AspNetCore.Http.Features;
using Microsoft.AspNetCore.Owin;
using Microsoft.Extensions.Options;
using Nowin;

namespace NowinSample
{
public class NowinServer : IServer                  //手动高亮
{
private INowinServer _nowinServer;
private ServerBuilder _builder;

public IFeatureCollection Features { get; } = new FeatureCollection();

public NowinServer(IOptions<ServerBuilder> options)
{
Features.Set<IServerAddressesFeature>(new ServerAddressesFeature());
_builder = options.Value;
}

public void Start<TContext>(IHttpApplication<TContext> application)
{
// Note that this example does not take into account of Nowin's "server.OnSendingHeaders" callback.
// Ideally we should ensure this method is fired before disposing the context.
Func<IDictionary<string, object>, Task> appFunc = async env =>
{
// The reason for 2 level of wrapping is because the OwinFeatureCollection isn't mutable
// so features can't be added
var features = new FeatureCollection(new OwinFeatureCollection(env));

var context = application.CreateContext(features);
try
{
await application.ProcessRequestAsync(context);
}
catch (Exception ex)
{
application.DisposeContext(context, ex);
throw;
}

application.DisposeContext(context, null);
};

// Add the web socket adapter so we can turn OWIN websockets into ASP.NET Core compatible web sockets.
// The calling pattern is a bit different
appFunc = OwinWebSocketAcceptAdapter.AdaptWebSockets(appFunc);

// Get the server addresses
var address = Features.Get<IServerAddressesFeature>().Addresses.First();

var uri = new Uri(address);
var port = uri.Port;
IPAddress ip;
if (!IPAddress.TryParse(uri.Host, out ip))
{
ip = IPAddress.Loopback;
}

_nowinServer = _builder.SetAddress(ip)
.SetPort(port)
.SetOwinApp(appFunc)
.Build();
_nowinServer.Start();
}

public void Dispose()
{
_nowinServer?.Dispose();
}
}
}

IServer

Features

Start

Start

builder

appFunc

Func

IWebHostBuilder

using System;
using Microsoft.AspNetCore.Hosting.Server;
using Microsoft.Extensions.DependencyInjection;
using Nowin;
using NowinSample;

namespace Microsoft.AspNetCore.Hosting
{
public static class NowinWebHostBuilderExtensions
{
public static IWebHostBuilder UseNowin(this IWebHostBuilder builder)        //手动高亮
{
return builder.ConfigureServices(services =>
{
services.AddSingleton<IServer, NowinServer>();
});
}

public static IWebHostBuilder UseNowin(this IWebHostBuilder builder, Action<ServerBuilder> configure)
{
builder.ConfigureServices(services =>
{
services.Configure(configure);
});
return builder.UseNowin();
}
}
}

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Hosting;

namespace NowinSample
{
public class Program
{
public static void Main(string[] args)
{
var host = new WebHostBuilder()
.UseNowin()                                     //手动高亮
.UseContentRoot(Directory.GetCurrentDirectory())
.UseIISIntegration()
.UseStartup<Startup>()
.Build();

host.Run();
}
}
}

Servers

在 OWIN-based 服务器上运行 ASP.NET Core 并使用 WebSockets 支持

public class Startup
{
public void Configure(IApplicationBuilder app)
{
app.Use(async (context, next) =>
{
if (context.WebSockets.IsWebSocketRequest)            //手动高亮
{                                                     //手动高亮
WebSocket webSocket = await context.WebSockets.AcceptWebSocketAsync();     //手动高亮
await EchoWebSocket(webSocket);                   //手动高亮
}
else
{
await next();
}
});

app.Run(context =>
{
return context.Response.WriteAsync("Hello World");
});
}

private async Task EchoWebSocket(WebSocket webSocket)
{
byte[] buffer = new byte[1024];
WebSocketReceiveResult received = await webSocket.ReceiveAsync(
new ArraySegment<byte>(buffer), CancellationToken.None);

while (!webSocket.CloseStatus.HasValue)
{
// Echo anything we receive
await webSocket.SendAsync(new ArraySegment<byte>(buffer, 0, received.Count),
received.MessageType, received.EndOfMessage, CancellationToken.None);

received = await webSocket.ReceiveAsync(new ArraySegment<byte>(buffer),
CancellationToken.None);
}

await webSocket.CloseAsync(webSocket.CloseStatus.Value,
webSocket.CloseStatusDescription, CancellationToken.None);
}
}
}

NowinServer

Configure

OWIN 键值

IDictionary<string,object>

请求数据 (OWIN v1.0.0)

String

String

String

String

String

String

IDictionary<string,string[]>

Stream

请求数据 (OWIN v1.1.0)

String

响应数据 (OWIN v1.0.0)

int

String

IDictionary<string,string[]>

Stream

其他数据 (OWIN v1.0.0)

CancellationToken

String

通用键值

X509Certificate

Func<Task>

String

String

String

String

bool

Action<Action<object>,object>

发送文件 v0.3.0

Opaque v0.3.0

String

OpaqueUpgrade

Stream

CancellationToken

WebSocket v0.3.0

String

WebSocketAccept

String

CancellationToken

int

String

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