使用DaprClient调用接口时CancellationToken无法取消请求的问题

我在Web API服务器上尝试通过DaprClient调用时使用CancellationToken取消长时间运行的请求，代码基于微软《Get started with Dapr》文档实现。

客户端调用代码（使用DaprClient） #

private static CancellationTokenSource cts;
public async Task OnGet()
{
    cts = new CancellationTokenSource();
    var forecasts = await _daprClient.InvokeMethodAsync<IEnumerable<WeatherForecast>>(
        HttpMethod.Get,
        "MyBackEnd",
        "weatherforecast",
        cts.Token);

    ViewData["WeatherForecastData"] = forecasts;
    cts.Dispose();
}

请求取消触发代码 #

public void OnPost()
{
    cts.Cancel();
    cts.Dispose();
    ViewData["WeatherForecastData"] = new List<WeatherForecast>();
}

服务端控制器代码 #

[HttpGet(Name = "GetWeatherForecast")]
public IEnumerable<WeatherForecast> Get(CancellationToken token)
{
    bool cancelled = false;
    token.Register(() => {
        Debug.WriteLine("Cancelled");
        cancelled = true;
    });

    List<WeatherForecast> forecasts = new List<WeatherForecast>();
    for (int i = 1; i < 6; i++)
    {
        if (cancelled)
        {
            Debug.WriteLine($"Cancelled after {i} iterations");
            break;
        }
        Debug.WriteLine($"Iter #{i}");
        forecasts.Add(new WeatherForecast
        {
            Date = DateTime.Now.AddDays(i),
            TemperatureC = Random.Shared.Next(-20, 55),
            Summary = Summaries[Random.Shared.Next(Summaries.Length)]
        });
        Task.Delay(1000).Wait();
    }

    return forecasts;
}

HttpClient直接调用的正常代码 #

private static CancellationTokenSource cts;
public async Task OnGet()
{
    cts = new CancellationTokenSource();
    string serverUrl = $"http://mybackend/WeatherForecast";
    List<WeatherForecast>? forecasts = await _httpClient.GetFromJsonAsync<List<WeatherForecast>>(serverUrl, cts.Token);
    ViewData["WeatherForecastData"] = forecasts;
    cts.Dispose();
}

问题现象 #

使用HttpClient直接调用时，取消操作可正常触发服务端停止处理；但使用上述DaprClient调用的方式时，触发取消后服务端代码仍会继续执行。推测该问题与Dapr Sidecar有关，需要实现请求取消的功能。示例项目已上传至GitHub仓库（garzooma/CancelDemoBlazor）

内容的提问来源于stack exchange，提问作者Greg Arzoomanian