.NET MAUI中System.Net.WebException: Connection reset错误求助

问题背景 #

在JSON模型中使用JsonCryption.Encryption和JsonCryption.Decryption加密算法，此前将API发布至Windows服务器测试时运行正常。服务器关闭后，通过本地IIS绑定域名重新发布API，当前客户端（Xamarin.Android）无法发送请求，抛出Connection Reset错误；此前Visual Studio本地运行API时也存在异常。

错误日志 #

{System.Net.WebException: Connection reset
 ---> Java.Net.SocketException: Connection reset
   at Java.Interop.JniEnvironment.InstanceMethods.CallIntMethod(JniObjectReference instance, JniMethodInfo method, JniArgumentValue* args) in /Users/runner/work/1/s/xamarin-android/external/Java.Interop/src/Java.Interop/obj/Release/net7.0/JniEnvironment.g.cs:line 11725
   at Java.Interop.JniPeerMembers.JniInstanceMethods.InvokeVirtualInt32Method(String encodedMember, IJavaPeerable self, JniArgumentValue* parameters) in /Users/runner/work/1/s/xamarin-android/external/Java.Interop/src/Java.Interop/Java.Interop/JniPeerMembers.JniInstanceMethods_Invoke.cs:line 511
   at Java.Net.HttpURLConnection.get_ResponseCode() in /Users/runner/work/1/s/xamarin-android/src/Mono.Android/obj/Release/net7.0/android-33/mcw/Java.Net.HttpURLConnection.cs:line 511
   at Xamarin.Android.Net.AndroidMessageHandler.<>c__DisplayClass132_0.<DoProcessRequest>b__2() in /Users/runner/work/1/s/xamarin-android/src/Mono.Android/Xamarin.Android.Net/AndroidMessageHandler.cs:line 577
   at System.Threading.Tasks.Task`1[[System.Net.HttpStatusCode, System.Net.Primitives, Version=7.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a]].InnerInvoke()
   at System.Threading.Tasks.Task.<>c.<.cctor>b__273_0(Object obj)
   at System.Threading.ExecutionContext.RunFromThreadPoolDispatchLoop(Thread threadPoolThread, ExecutionContext executionContext, ContextCallback callback, Object state)
--- End of stack trace from previous location ---
   at System.Threading.ExecutionContext.RunFromThreadPoolDispatchLoop(Thread threadPoolThread, ExecutionContext executionContext, ContextCallback callback, Object state)
   at System.Threading.Tasks.Task.ExecuteWithThreadLocal(Task& currentTaskSlot, Thread threadPoolThread)
--- End of stack trace from previous location ---
   at Xamarin.Android.Net.AndroidMessageHandler.DoProcessRequest(HttpRequestMessage request, URL javaUrl, HttpURLConnection httpConnection, CancellationToken cancellationToken, RequestRedirectionState redirectState) in /Users/runner/work/1/s/xamarin-android/src/Mono.Android/Xamarin.Android.Net/AndroidMessageHandler.cs:line 577
   at Xamarin.Android.Net.AndroidMessageHandler.DoSendAsync(HttpRequestMessage request, CancellationToken cancellationToken) in /Users/runner/work/1/s/xamarin-android/src/Mono.Android/Xamarin.Android.Net/AndroidMessageHandler.cs:line 417
  --- End of managed Java.Net.SocketException stack trace ---
java.net.SocketException: Connection reset
    at java.net.SocketInputStream.read(SocketInputStream.java:215)
    at java.net.SocketInputStream.read(SocketInputStream.java:144)
    at com.android.okhttp.okio.Okio$2.read(Okio.java:138)
    at com.android.okhttp.okio.AsyncTimeout$2.read(AsyncTimeout.java:213)
    at com.android.okhttp.okio.RealBufferedSource.indexOf(RealBufferedSource.java:307)
    at com.android.okhttp.okio.RealBufferedSource.indexOf(RealBufferedSource.java:301)
    at com.android.okhttp.okio.RealBufferedSource.readUtf8LineStrict(RealBufferedSource.java:197)
    at com.android.okhttp.internal.http.Http1xStream.readResponse(Http1xStream.java:188)
    at com.android.okhttp.internal.http.Http1xStream.readResponseHeaders(Http1xStream.java:129)
    at com.android.okhttp.internal.http.HttpEngine.readNetworkResponse(HttpEngine.java:750)
    at com.android.okhttp.internal.http.HttpEngine.readResponse(HttpEngine.java:622)
    at com.android.okhttp.internal.huc.HttpURLConnectionImpl.execute(HttpURLConnectionImpl.java:475)
    at com.android.okhttp.internal.huc.HttpURLConnectionImpl.getResponse(HttpURLConnectionImpl.java:411)
    at com.android.okhttp.internal.huc.HttpURLConnectionImpl.getResponseCode(HttpURLConnectionImpl.java:542)

  --- End of managed Java.Net.SocketException stack trace ---
java.net.SocketException: Connection reset
    at java.net.SocketInputStream.read(SocketInputStream.java:215)
    at java.net.SocketInputStream.read(SocketInputStream.java:144)
    at com.android.okhttp.okio.Okio$2.read(Okio.java:138)
    at com.android.okhttp.okio.AsyncTimeout$2.read(AsyncTimeout.java:213)
    at com.android.okhttp.okio.RealBufferedSource.indexOf(RealBufferedSource.java:307)
    at com.android.okhttp.okio.RealBufferedSource.indexOf(RealBufferedSource.java:301)
    at com.android.okhttp.okio.RealBufferedSource.readUtf8LineStrict(RealBufferedSource.java:197)
    at com.android.okhttp.internal.http.Http1xStream.readResponse(Http1xStream.java:188)
    at com.android.okhttp.internal.http.Http1xStream.readResponseHeaders(Http1xStream.java:129)
    at com.android.okhttp.internal.http.HttpEngine.readNetworkResponse(HttpEngine.java:750)
    at com.android.okhttp.internal.http.HttpEngine.readResponse(HttpEngine.java:622)
    at com.android.okhttp.internal.huc.HttpURLConnectionImpl.execute(HttpURLConnectionImpl.java:475)
    at com.android.okhttp.internal.huc.HttpURLConnectionImpl.getResponse(HttpURLConnectionImpl.java:411)
    at com.android.okhttp.internal.huc.HttpURLConnectionImpl.getResponseCode(HttpURLConnectionImpl.java:542)

   --- End of inner exception stack trace ---
   at Xamarin.Android.Net.AndroidMessageHandler.DoSendAsync(HttpRequestMessage request, CancellationToken cancellationToken) in /Users/runner/work/1/s/xamarin-android/src/Mono.Android/Xamarin.Android.Net/AndroidMessageHandler.cs:line 431
   at System.Net.Http.HttpClient.<SendAsync>g__Core|83_0(HttpRequestMessage request, HttpCompletionOption completionOption, CancellationTokenSource cts, Boolean disposeCts, CancellationTokenSource pendingRequestsCts, CancellationToken originalCancellationToken)
   at Kuber.UI.Services.HttpClientService.<SendAsync>d__2`1[[System.String, System.Private.CoreLib, Version=7.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]].MoveNext() in C:\Github\Kuber.UI\Kuber.UI\Services\Concrete\HttpClientService.cs:line 32}

客户端请求代码 #

public async Task<ResponseModel<TEntity>> SendAsync<TEntity>(HttpMethod method, string requestUri, object content)
{
    try
    {
        var url = new Uri(App.KuberURL + requestUri);
        var request = new RequestModel
        {
            model = JsonCryption.Encryption(JsonConvert.SerializeObject(content))
        };
        var cryptionContent = new StringContent(JsonConvert.SerializeObject(request), Encoding.UTF8, "application/json");
        HttpRequestMessage httpRequestMessage = new HttpRequestMessage(method, url);
        httpRequestMessage.Content = cryptionContent;
        var response = await _httpClient.SendAsync(httpRequestMessage);
        response.EnsureSuccessStatusCode();
        var json = await response.Content.ReadAsStringAsync();
        var responseModel = JsonConvert.DeserializeObject<ResponseModel<TEntity>>(JsonCryption.Decryption(json));

        return responseModel;
    }
    catch(TimeoutException ex)
    {
        return null;
    }
    catch (WebException ex)
    {
        return null;
    }
    catch (Exception ex)
    {
        return null;
        //throw new Exception();
    }
}
public class ResponseModel<TEntity>
{
    public TEntity Value { get; set; }
    public int ErrorCode { get; set; }
    public string ErrorMessage { get; set; }
}

排查方向与解决思路 #

• 网络连通性验证

  • 在客户端设备上用浏览器直接访问API绑定的域名，确认是否能正常获取响应（比如Swagger页面），排除DNS解析或路由问题。
  • 检查本地防火墙是否开放了API绑定的端口，同时确认端口未被其他程序占用。
  • 若使用HTTPS，需确保安卓设备信任本地IIS的SSL证书（自签证书需手动安装到设备信任列表）。

• IIS配置检查

  • 确认IIS应用程序池的.NET版本与API的目标框架匹配（比如API为.NET 7，应用程序池需对应选择.NET 7或无托管代码）。
  • 检查站点绑定的主机头、端口与客户端请求的地址完全一致，避免因绑定规则不匹配导致请求被拒绝。
  • 查看IIS日志（默认路径C:\inetpub\logs\LogFiles），确认请求是否到达服务器，以及服务器返回的具体状态码。

• 加密逻辑隔离测试

  • 临时注释掉JsonCryption加密/解密代码，发送明文请求，验证是否能正常通信，排除加密逻辑导致的请求格式错误。
  • 检查加密后的内容是否包含特殊字符，导致请求体不符合application/json规范，可对加密结果进行URL编码后再封装到请求体。

• HttpClient配置优化

  • 确认App.KuberURL的域名、端口拼写正确，无多余路径或字符。
  • 调整HttpClient的超时时间，避免因服务器处理缓慢导致连接被重置。
  • 尝试将Xamarin.Android的AndroidMessageHandler替换为HttpClientHandler，排查是否为安卓系统网络处理组件的问题。

• 服务器端日志补充

  • 在API中添加详细日志，记录请求到达时间、请求体内容、解密过程、异常信息，确认服务器是否接收并处理了请求，以及处理过程中是否出现未捕获的异常。

内容的提问来源于stack exchange，提问作者Mustafa Gönültaş