Droid API "Network subsystem is down"

[BullT]

Hi,

I'm doing a Uno Platform to consume API.

When I run de APP in UWP, it works fine, but when I run it on Android throw an exception "Network subsystem is down".
The exception appears on this line:

HttpResponseMessage response = await client.PostAsync("api/Account/Login", content);

I've modified the AndroidManifest to give access to Internet

AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android" package="ProPar.Uno" android:versionCode="1" android:versionName="1.0" android:installLocation="auto">
	<uses-sdk android:minSdkVersion="16" android:targetSdkVersion="29" />
	<uses-permission android:name="android.permission.INTERNET" />
	<application android:label="ProPar.Uno"></application>
</manifest>

ApiService.cs

using Newtonsoft.Json;
using ProPar.Uno.Models;
using System;
using System.Net.Http;
using System.Text;
using System.Threading.Tasks;

namespace ProPar.Uno.Helpers
{
    public class ApiService
    {
        public static async Task<Response> LoginAsync(LoginRequest model)
        {
            try
            {
                string request = JsonConvert.SerializeObject(model);
                StringContent content = new StringContent(request, Encoding.UTF8, "application/json");

                HttpClientHandler handler = new HttpClientHandler()
                {
                    ServerCertificateCustomValidationCallback = HttpClientHandler.DangerousAcceptAnyServerCertificateValidator
                };

                HttpClient client = new HttpClient(handler)
                {
                    BaseAddress = new Uri("https://localhost:44392/")
                };

                HttpResponseMessage response = await client.PostAsync("api/Account/Login", content);
                string result = await response.Content.ReadAsStringAsync();
                if (!response.IsSuccessStatusCode)
                {
                    return new Response
                    {
                        IsSuccess = false,
                        Message = result
                    };
                }

                User user = JsonConvert.DeserializeObject<User>(result);
                return new Response
                {
                    IsSuccess = true,
                    Result = user,
                };

            }
            catch (Exception ex)
            {
                return new Response
                {
                    IsSuccess = false,
                    Message = ex.Message
                };
            }
        }
    }
}

How can I solve the concern?

Thanks,
BullT

[jeromelaban]

Can you provide the full exception stack trace?

[jeromelaban]

It looks like you're trying to access localhost. It's likely not what you want, as localhost is the device itself, not the API server you're running on your machine. Try using your machine's IP address instead.

[BullT]

Hi Jerome,

Solved!
That was the solution.

Thanks,
BullT

[BullT]

Hi Jerome,

I'm not sure if it is this that you want:

Message ---
Network subsystem is down
HelpLink ---
Source ---
mscorlib
StackTrace ---
  at System.Net.Http.ConnectHelper.ConnectAsync (System.String host, System.Int32 port, System.Threading.CancellationToken cancellationToken) [0x00180] in /Users/builder/jenkins/workspace/archive-mono/2020-02/android/release/external/corefx/src/System.Net.Http/src/System/Net/Http/SocketsHttpHandler/ConnectHelper.cs:84 
  at System.Threading.Tasks.ValueTask`1[TResult].get_Result () [0x0001b] in /Users/builder/jenkins/workspace/archive-mono/2020-02/android/release/external/corefx/src/Common/src/CoreLib/System/Threading/Tasks/ValueTask.cs:813 
  at System.Threading.Tasks.ValueTask`1[TResult].get_Result () [0x0001b] in /Users/builder/jenkins/workspace/archive-mono/2020-02/android/release/external/corefx/src/Common/src/CoreLib/System/Threading/Tasks/ValueTask.cs:813 
  at System.Net.Http.HttpConnectionPool.WaitForCreatedConnectionAsync (System.Threading.Tasks.ValueTask`1[TResult] creationTask) [0x000a2] in /Users/builder/jenkins/workspace/archive-mono/2020-02/android/release/external/corefx/src/System.Net.Http/src/System/Net/Http/SocketsHttpHandler/HttpConnectionPool.cs:543 
  at System.Threading.Tasks.ValueTask`1[TResult].get_Result () [0x0001b] in /Users/builder/jenkins/workspace/archive-mono/2020-02/android/release/external/corefx/src/Common/src/CoreLib/System/Threading/Tasks/ValueTask.cs:813 
  at System.Net.Http.HttpConnectionPool.SendWithRetryAsync (System.Net.Http.HttpRequestMessage request, System.Boolean doRequestAuth, System.Threading.CancellationToken cancellationToken) [0x0003f] in /Users/builder/jenkins/workspace/archive-mono/2020-02/android/release/external/corefx/src/System.Net.Http/src/System/Net/Http/SocketsHttpHandler/HttpConnectionPool.cs:284 
  at System.Net.Http.RedirectHandler.SendAsync (System.Net.Http.HttpRequestMessage request, System.Threading.CancellationToken cancellationToken) [0x00070] in /Users/builder/jenkins/workspace/archive-mono/2020-02/android/release/external/corefx/src/System.Net.Http/src/System/Net/Http/SocketsHttpHandler/RedirectHandler.cs:32 
  at System.Net.Http.HttpClient.FinishSendAsyncBuffered (System.Threading.Tasks.Task`1[TResult] sendTask, System.Net.Http.HttpRequestMessage request, System.Threading.CancellationTokenSource cts, System.Boolean disposeCts) [0x0017e] in /Users/builder/jenkins/workspace/archive-mono/2020-02/android/release/external/corefx/src/System.Net.Http/src/System/Net/Http/HttpClient.cs:506 
  at ProPar.Uno.Helpers.ApiService.LoginAsync (ProPar.Uno.Models.LoginRequest model) [0x000a8] in E:\GitHub\ProPar\ProPar.Uno\ProPar.Uno.Shared\Helpers\ApiService.cs:29 
TargetSite ---

[jeromelaban]

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