无法使用Angular 5客户端启动与信号器核心集线器的连接

Question

我有一个运行SignalR核心集线器的.Net Core 2.0 C#Web Api.我甚至无法启动()我的hubConnection从angular(5.0.1)收到此错误:

选项https:// localhost:44301/hubs/sample 405(方法不允许)

错误:无法启动连接.错误:方法不允许

建立连接时出错:(

XHR加载失败:OPTIONS" https:// localhost:44301/hubs/sample ".

HttpError:XMLHttpRequest.xhr.onload不允许的方法[as __zone_symbol__ON_PROPERTYload](webpack-internal:///../../../../@aspnet/signalr-client/dist/src/HttpClient.js: 30:28)在ZoneDelegate.invokeTask(webpack-internal)的XMLHttpRequest.wrapFn(webpack-internal:///../../../../zone.js/dist/zone.js:1166:39) :///../../../../zone.js/dist/zone.js:425:31)在Object.onInvokeTask(webpack-internal:///../../ .. /core/esm5/core.js:4816:33)在ZoneDelegate.invokeTask(webpack-internal:///../../../../zone.js/dist/zone.js:424:36 )在Zone.runTask(webpack-internal:///../../../../zone.js/dist/zone.js:192:47)的ZoneTask.invokeTask [作为调用](webpack-)内部:///../../../../zone.js/dist/zone.js:499:34)在invokeTask(webpack-internal:///../../../) ../zone.js/dist/zone.js:1540:14)在XMLHttpRequest.globalZoneAwareCallback(webpack-internal:///../../../../zone.js/dist/zone.js :1566:17)

我正在努力甚至调试这个问题,即使在小提琴手的帮助下我也无法解决它.它似乎不是我的Api的问题,因为Kestrel控制台打印出来到集线器的请求进来,但不会打印任何错误.而且我可以毫无问题地获取,发送和发布到我的控制器.

这是我的StartUp.cs配置(我省略了与简洁无关的代码)

public void ConfigureServices(IServiceCollection services)
{
    services.AddCors(options =>
    {
        options.AddPolicy(
            "CorsPolicy",
            builder =>
                builder
                .AllowAnyOrigin()
                .AllowAnyHeader()
                .AllowAnyMethod()
                .AllowCredentials()
        );
    });

    services.AddAuthentication();
    services.AddMvcCore()
        .AddAuthorization(options => {...});
    services.AddAuthentication("Bearer")
        .AddIdentityServerAuthentication(options => {...});

    services.AddSignalR();
}

public void Configure(IApplicationBuilder app, IHostingEnvironment env)
{
    app.UseCors("CorsPolicy");
    app.UseAuthentication();

    app.UseSignalR(routes =>
    {
        routes.MapHub<SampleHub>("/hubs/sample");
    });

    app.UseMvc();
}

这是我的示例中心

public interface ISampleHubClient 
{
    Task receiveMessage(SampleRequest msg);
}

public class SampleHub : Hub<ISampleHubClient>
{
    private static string _connectionId;

    public async Task Subscribe(string groupName)
    {
        await Groups.AddAsync(Context.ConnectionId, groupName);

        await Clients.Client(Context.ConnectionId).receiveMessage("Subscribed to " + groupName);
    }

    /// <inheritdoc />
    public Task Send(SampleRequest msg)
    {
        ConsoleColor.Green.WriteLine("Send : " + _connectionId);

        return Clients.Group(msg.Group).receiveMessage(msg);
    }
}

这是我的Angular组件代码:

import { HubConnection } from '@aspnet/signalr-client';

@Component({})
export class SignalRTestComponent implements OnInit {
    private hubConnection: HubConnection;

    ngOnInit() {
        this.initHub();
    }

    initHub()
    {
        let self = this;
        var signalrBaseUri = "https://localhost:44301/hubs/sample";

       this.hubConnection = new HubConnection(signalrBaseUri);

        this.hubConnection
        .start() // <- Failure here
        .then(() =>{
             self.hubConnection.invoke("Subscribe", this.groupName);
        })
        .catch(err => { console.log("INVOKE FAILED");console.error(err);});             
    })
    .catch(err => 
    {
        console.log('Error while establishing connection :(');
        console.log(err);
    });

    this.hubConnection.on('receiveMessage', (receivedMessage: SampleMessage) => {
        console.log("Message received : ");
        console.log(sampleMessage);
    });
}
}

任何帮助将不胜感激

Answer 1

问题是,故宫包已被重命名,从@aspnet/signalr-client到@aspnet/signalr.更改为新包并修复导入对我有用(至少摆脱OPTIONS调用错误.

import { HubConnection } from '@aspnet/signalr'

Answer 2

帕维尔的评论让我找到了解决这个问题的正确方向。

以下是一些讨论 OPTIONS 请求和替换它的决定的帖子。

https://github.com/aspnet/SignalR/issues/1107

https://github.com/aspnet/SignalR/issues/1111

然而，我的问题似乎已经通过纠正 nuget 包版本的错误得到解决。

我意识到我的 SignalR Hub 项目引用了 Microsoft.AspNetCore.SignalR 的预览版 (2.1.0-preview1-27884)。我将其更改为使用1.0.0-alpha2-final。我还清除了我的 node_modules 目录，验证了我的 npm 缓存，并再次重新安装了所有内容

npm cache verify
npm install

现在一切正常。