I have built an API with Spring-Boot, which send some JSON as response.
After I set the #CrossOrigin-Annotation on my Spring-Boot-App, I‘m able to fetch the data without any problem.
Now I want to fetch from the same API with my React-Native-App (running with Expo App (iOS)).
Unfortunately I only get an Network-Error.
I added Localhost:19002, the IP from the Expo-Server and my Phone-IP to the CrossOrigin-Annotation.
Same Error.
The API should be fine, so my Question is:
What IP is Expo using, to fetch my Data from the API?
I hope, someone can help me - as I‘m pretty new to this (Web)App-Topic
Greetings
Daniel
If you are running the Expo client app on your device, localhost will refer to your phone and not your computer.
You will need to use your network ip address for your computer to reach it. You can get that programmatically while in development by using Constants.manifest.hostUri but that will include the port as well.
// be sure to run expo install expo-constants first
import * as Constants from 'expo-constants';
let host;
if (__DEV__) {
// eg: 192.168.1.1:19000 -> 192.168.1.1
host = Constants.manifest.hostUri.split(':')[0];
} else {
host = 'https://your-production-server-url.com/api'
}
Related
I am trying to connect to one of mine IOT ESP32 based web server from Xamarin Android native based project with the following code:
client = new HttpClient();
Uri uri = new Uri( "http://192.168.0.5/sensors" );
client.Timeout = TimeSpan.FromSeconds(10);
HttpResponseMessage response = client.GetAsync( uri ).GetAwaiter().GetResult();
if( response.IsSuccessStatusCode )
{
string content = response.Content.ReadAsStringAsync().GetAwaiter().GetResult();
}
Yet seems like the timout is ignored, and with or without it I am receiving
System.Net.Http.HttpRequestException: 'No route to host'
How to properly connect from Xamarin Android native app to an address inside my local network ?
What is causing this exception ?
The network is all fine, and the server is reachable from practically any other OS, including microcontrollers within it except Android.
Found workaround - redirecting port from the router to the server, and using external IP on this port seems like working.
I have been following this link to understand how to use HttpClient to call a Web API Method.
https://www.tutorialsteacher.com/webapi/consuming-web-api-in-dotnet-using-httpclient
The code of interest in the article is below with ‘client’ being the HttpClient object:
client.BaseAddress = new Uri("http://localhost:60464/api/"); //HTTP GET
var responseTask = client.GetAsync("student");
responseTask.Wait();
var result = responseTask.Result;
Error results as follows:
System.AggregateException: 'One or more errors occurred. (Failed to connect to localhost/127.0.0.1:443)'
Please understand my background in networking, IIS and the like is very limited.Most of my time is spent in code and SQL Sprocs. This is a personal project so I have to get this setup myself
If I replace localhost with my machines IP I get the following error:
One or more errors occurred. (java.security.cert.CertPathValidatorException: Trust anchor for certification path not found.)'
So two questions:
How do I install this needed certificate or settings or otherwise (again no idea about this configuration network stuff) but I do have IIS up and running with the Web API hosted and working
If using ‘localhost’ is not supposed to work, what might be the reason this article is using it?
This is only for a personal development machine, yes at some point I am going to want it to work in the real world but for now I just need to get some ‘hello world’ stuff going before the end of times.
I can not find how to start WPS client in Windows 10 from command prompt or powershell. When I used Linux, everything was really ease with wla_supplicant (wpa_cli wps_pbc). Is there something similar in Windows?
Does anyone know how to set up Wi-Fi network (over WPS) key without human input in Windows?
I also tried WCN (Windows Connect Now) from Microsoft as it implements WPS features. I got also samples from Windows SDK on WCN, but they could not get key by WPS (it faild). But if I use Windows user interface to connect wiothout PIN, everyting seems to be pretty fine.
I am sure that there is possibility to do that, it is very important to perform Wifi Protected Setup by button start from the command prompt or app (C++/C#) without human intrusion or input (once WPS is on air, Windows should automatically get the network key and connect then).
I don't know if it's too late to answer, just put what I know in here and hope it can help.
First, if your system has updated to 16299(Fall Creator Update), you can just simply use new wifi api from UWP.
Install newest Windows SDK, create a C# console project, target C# version to at least 7.1, then add two reference to the project.
C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework.NETCore\v4.5\System.Runtime.WindowsRuntime.dll
C:\Program Files (x86)\Windows Kits\10\UnionMetadata\10.0.16299.0\Windows.winmd
After all of that , code in below should work.
using System;
using System.Threading.Tasks;
using Windows.Devices.Enumeration;
using Windows.Devices.WiFi;
class Program
{
static async Task Main(string[] args)
{
var dic = await DeviceInformation.FindAllAsync(WiFiAdapter.GetDeviceSelector());
if (dic.Count > 0)
{
var adapter = await WiFiAdapter.FromIdAsync(dic[0].Id);
foreach (var an in adapter.NetworkReport.AvailableNetworks)
{
if (an.Ssid == "Ssid which you want to connect to.")
{
// Fouth parameter which is ssid can not be set to null even if we provided
// first one, or an exception will be thrown.
await adapter.ConnectAsync(an, WiFiReconnectionKind.Manual, null, "",
WiFiConnectionMethod.WpsPushButton);
}
}
}
}
}
Build and run the exe, then push your router's button, your pc will be connect to the router.
But if you can not update to 16299, WCN will be your only choice. You may already notice that if call IWCNDevic::Connect frist with push-button method, the WSC(Wifi Simple Configuration) session will fail. That's because WNC would not start a push-button session as a enrollee, but only as a registrar. That means you have to ensure that router's button has been pushed before you call IWCNDevic::Connect. The way to do that is using Native Wifi api to scan your router repeatedly, analyse the newest WSC information element from the scan result, confirm that Selected Registrar attribute has been set to true and Device Password Id attribute has been set to 4. After that, query the IWCNDevice and call Connect function will succeed. Then you can call IWCNDevice::GetNetworkProfile to get a profile that can use to connect to the router. Because it's too much of code, I will only list the main wifi api that will be used.
WlanEnuminterfaces: Use to get a available wifi interface.
WlanRegisterNotification: Use to register a callback to handle scan an connect results.
WlanScan: Use to scan a specified wifi BSS.
WlanGetNetworkBsslist: Use to get newest BSS information after scan.
WlanSetProfile: Use to save profile for a BSS.
WlanConnect: Use to connect to a BSS.
And about the WSC information element and it's attributes, you can find all the information from Wi-Fi Simple Configuration Technical Specification v2.0.5.
For Krisz. About timeout.
You can't cast IAsyncOperation to Task directly. The right way to do that is using AsTask method. And also, you should cancel ConnectAsync after timeout.
Sample code:
var t = adapter.ConnectAsync(an, WiFiReconnectionKind.Manual, null, "",
WiFiConnectionMethod.WpsPushButton).AsTask();
if (!t.Wait(10000))
t.AsAsyncOperation().Cancel();
This may well be a duplicate question, but no answer from an existing question has solved my problem.
I have a WebAPI end point running on my dev machine. I've configured it to run on
.UseUrls("http://localhost:57971", "http://10.0.2.2:57971", "http://192.168.44.1:57971", "http://192.168.1.48:57971", "http://*:57971")
where:
192.168.44.1 is Desktop Adapter #2 on the emulator Networks settings tab
10.0.2.2 is the special address for the Android emulator, as set out in Google's doco (possibly not relevant to Xamarin) and
192.168.1.48 is my local IP address for my dev machine.
I have created a firewall rule permitting connections on TCP port 57971.
I researched this pretty heavily and heeded instructions such as those set out here http://briannoyesblog.azurewebsites.net/2016/03/06/calling-localhost-web-apis-from-visual-studio-android-emulator/
I'm kinda out of ideas. The annoying thing is, it fails silently. There is no exception and the output just basically shows the different threads exiting with code 0. And the application keeps running i.e. the debugging session is not returning the IDE to a "code entry" state. This may suggest that something else its at play here.
The code looks pretty innocuous to me:
protected async Task<T> GetAsync<T>(string url)
where T : new()
{
HttpClient httpClient = CreateHttpClient();
T result;
try
{
var response = await httpClient.GetStringAsync(url);
result = await Task.Run(() => JsonConvert.DeserializeObject<T>(response));
}
catch
{
result = new T();
}
return result;
}
I'm using Visual Studio 2015.
I'm using the Visual Studio emulator https://www.visualstudio.com/vs/msft-android-emulator/
Any idea how I can get wheels on the ground on this thing?
Is there a way to Ping my machine from the emulator?
Thanks
I got this working by using 169.254.80.80 i.e. I added it to the list of urls which the API serves and called that ip address from the Xamarin app.
So, in Program.cs became simple:
.UseUrls("http://localhost:57971", "http://169.254.80.80:57971")
I also had to add it to the bindings element ApplicationConfig file in the hidden .vs folder of the ASP.NET API solution. Not sure why it had to be 169.254.80.80, as that was Desktop Adapter #4.
That got it working.
I'm testing out deploying my own parse server following the steps in the Parse Server Guide. I've got the server up and running and have been able to create and fetch objects via curl. I built a simple iOS app using the Parse SDK (1.14.2). I've initialized the SDK with the app id and server url as described in the Parse Server Guide. When I try to make requests, I get back unauthorized from the server. Digging further, I noticed that the SDK is not sending the application id header to the server. I modified the SDK to send the application id header and everything works. Am I missing a configuration step somewhere?
This is because you are not passing the ClientKey. In swift 3 you would pass it like this in the didFinishLaunchingWithOptions.
// Init Parse
let configuration = ParseClientConfiguration {
$0.applicationId = PARSE_APP_KEY
$0.clientKey = PARSE_CLIENT_KEY
$0.server = PARSE_SERVER_URL
$0.isLocalDatastoreEnabled = true
}
Parse.initialize(with: configuration)
If you are falling when trying to test CloudCode, then its because your parse-server is not passing the Javascript key. So just make sure you initialize the server to do so if this issue is related to Parse.Cloud function.