C# 发送大型JSON文件（>；1 MB）时HttpClient.SendAsync抛出System.Net.Http.HttpRequestException

我有一个以RESTful方式在HTTP协议上工作的外部web服务。它可以接受相当大的JSON文档（从1MB到20-30MB），进行一些转换并返回另一个大的JSON文档，该文档的大小等于或不小于接受的JSON文档的大小

当通过邮递员进行测试时，它运行良好

我使用ASP.NET Core 2.2，并尝试使用

HttpClient

执行相同的请求。我的应用程序接受数据，创建相同的JSON文档并将其发送到外部web服务

下面是我使用的代码：

public async Task<TResponse> MakeRequest<TRequest, TResponse>(TRequest request)
{
        if (request == null)
            throw new ArgumentNullException(nameof(TRequest));

        var content = new StringContent(JsonConvert.SerializeObject(request));
        content.Headers.ContentType = new MediaTypeHeaderValue("application/json");
        var httpRequestMessage = new HttpRequestMessage { Method = HttpMethod.Post, Content = content };

        var response = await _httpClient.SendAsync(httpRequestMessage);

        if (response.IsSuccessStatusCode)
        {
            string responseString = await response.Content.ReadAsStringAsync();
            var responseObject = JsonConvert.DeserializeObject<TResponse>(responseString);
            return (responseObject != null) ? responseObject : throw new InvalidOperationException();
        }
        throw new InvalidOperationException();
}

你知道是什么导致了这个问题吗

更新-异常.ToString（）消息：

---

例外说明了什么？是400吗？500美元？它是否包含错误消息？如果服务器返回无效响应，它似乎无法处理大型JSON文件。再说一次，您确定没有收到错误页面而不是实际响应吗？尝试使用Fiddler或其他调试代理查看从server@PanagiotisKanavos，异常表示“服务器返回了无效或无法识别的响应”。@PanagiotisKanavos，服务器在使用Postman进行测试时返回了有效响应。HttpException包括状态代码，假设服务器返回了一个。异常的状态代码是什么？发布完整的异常文本，而不仅仅是消息。您可以使用

Exception.ToString（）

获取全文。但是，如果服务器将您重定向到错误页面，则只有Fiddler会显示该页面

services.AddHttpClient<IExternalWebServiceProxy, ExternalWebServiceProxy>()
            .ConfigureHttpClient(x =>
            {
                x.MaxResponseContentBufferSize = 1024 * 1000 * 100;
            });

System.Net.Http.HttpRequestException: An error occurred while sending the request. ---> System.IO.IOException: The server returned an invalid or unrecognized response.
   at System.Net.Http.HttpConnection.SendAsyncCore(HttpRequestMessage request, CancellationToken cancellationToken)
   --- End of inner exception stack trace ---
   at System.Net.Http.HttpConnection.SendAsyncCore(HttpRequestMessage request, CancellationToken cancellationToken)
   at System.Net.Http.HttpConnectionPool.SendWithNtConnectionAuthAsync(HttpConnection connection, HttpRequestMessage request, Boolean doRequestAuth, CancellationToken cancellationToken)
   at System.Net.Http.HttpConnectionPool.SendWithRetryAsync(HttpRequestMessage request, Boolean doRequestAuth, CancellationToken cancellationToken)
   at System.Net.Http.RedirectHandler.SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
   at System.Net.Http.HttpClient.FinishSendAsyncBuffered(Task`1 sendTask, HttpRequestMessage request, CancellationTokenSource cts, Boolean disposeCts)
   at XXX.XXX.XXX.Internals.NCANodeProxy.MakeRequest[TRequest,TResponse](TRequest request) in D:\Sources\XXX\XXX\XXX.XXX.Core\Internals\ExternalNodeProxy.cs:line 36
   at XXX.XXX.XXX.Services.CryptoService.SignFileDocument(SignFileCommand command) in D:\Sources\XXX\XXX\XXX.XXX.Core\Services\CryptoService.cs:line 134