转换为 Powershell 的工作 C# 代码导致 SocketException

Question

我有以下成功调用 HTTP Post 端点的 C# 控制台应用程序：

class Program
{
    static void Main(string[] args)
    {
        HttpClient httpClient = new HttpClient();
        httpClient.BaseAddress = new Uri("https://DomainOne.azure-api.net");
        httpClient.DefaultRequestHeaders.Add("Ocp-Apim-Subscription-Key", "8b17badbbfe44e9e933453a8b4d8fc85");

        StringContent stringContent = new StringContent("\"hi\"", System.Text.Encoding.UTF8, "application/json");            
        Task<HttpResponseMessage> task = httpClient.PostAsync("integration/api/Result/CompanyOne", stringContent);
        HttpResponseMessage response = task.Result;

        var content = response.Content.ReadAsStringAsync().Result;
    }
}

这是我尝试使用的等效 Powershell 脚本：

$httpClient = New-Object 'System.Net.Http.HttpClient'
$httpClient.BaseAddress = New-Object 'System.Uri'('https://DomainOne.azure-api.net')
$httpClient.DefaultRequestHeaders.Add("Ocp-Apim-Subscription-Key", "8b17badbbfe44e9e933453a8b4d8fc85");

$stringContent = New-Object 'System.Net.Http.StringContent'('"hi"', [System.Text.Encoding]::UTF8, 'application/json')
$task = $httpClient.PostAsync('integration/api/Result/CompanyOne', $stringContent)
$response = $task.Result

$content = $response.Content.ReadAsStringAsync().Result

但是 $task 对象包含以下内容：

System.AggregateException: One or more errors occurred. 
---> System.Net.Http.HttpRequestException: An error occurred while sending the request. 
---> System.Net.WebException: The underlying connection was closed: An unexpected error occurred on a send. 
---> System.IO.IOException: Unable to read data from the transport connection: An existing connection was forcibly closed by the remote host. 
---> System.Net.Sockets.SocketException: An existing connection was forcibly closed by the remote host
at System.Net.Sockets.Socket.EndReceive(IAsyncResult asyncResult)
at System.Net.Sockets.NetworkStream.EndRead(IAsyncResult asyncResult)
--- End of inner exception stack trace ---
at System.Net.TlsStream.EndWrite(IAsyncResult asyncResult)
at System.Net.ConnectStream.WriteHeadersCallback(IAsyncResult ar)
--- End of inner exception stack trace ---
at System.Net.HttpWebRequest.EndGetRequestStream(IAsyncResult asyncResult, TransportContext& context)
at System.Net.Http.HttpClientHandler.GetRequestStreamCallback(IAsyncResult ar)
--- End of inner exception stack trace ---

端点托管在我们 API 管理后面的开发 Azure 环境中，操作 method/controller 如下所示：

[ApiController]
[Route("api/[controller]")]
public class ResultController : ControllerBase
{                           
    [Route("{providerName}")]
    [HttpPost]
    public Task<bool> ReceiveMessage(HL7Message message)
    {
        return Task.FromResult(true);
    }
}

这是 Azure API 管理中的协议设置：

为什么我在 Powershell 中得到了 SocketException 而在 C# 中却没有，我怎样才能让它在 Powershell 中工作？

Answer 1

基于Rick Rainey's helpful comment，您可以通过在 HTTP 调用之前添加以下代码行来强制使用 TLS 版本：

[System.Net.ServicePointManager]::SecurityProtocol = [System.Net.SecurityProtocolType]::Tls12

我认为这是所用 .NET 版本的限制。低于 .NET 4.6 的任何版本都将默认使用非 1.2 的 TLS 版本。

转换为 Powershell 的工作 C# 代码导致 SocketException

Working C# code converted to Powershell results in SocketException

powershell

http

azure

azure-api-management

asp.net-core