Using Websockets with Azure Websites - Error during WebSocket handshake - asp.net

I am using Azure websites. In my ASP Net MVC project I created a websocket server and client. When trying to call my server I get
WebSocket connection to 'ws://binfx.azurewebsites.net/WebSocketServer.ashx' failed: Error during WebSocket handshake: net::ERR_CONNECTION_RESET
My server class is:
WebSocketServer.ashx
public class WebSocketServer : IHttpHandler
{
public void ProcessRequest(HttpContext context)
{
if (context.IsWebSocketRequest)
{
context.Response.ContentType = "text/plain";
context.Response.Write("Hello World");
context.AcceptWebSocketRequest(new MicrosoftWebSockets());
}
else
{
context.Response.ContentType = "text/plain";
context.Response.Write("Not a websocket response!");
context.Response.StatusCode=400;
}
}
}
My client code is:
Index.cshtml
window.onload = function () {
var conversation = $('body');
var localHost = window.document.location.host;
var url = "ws://" + localHost + "/WebSocketServer.ashx";
if (window.WebSocket) {
var ws = new WebSocket(url);
ws.onmessage = function (response) {
conversation.append(createSpan('Response:' + response.data));
}
ws.onopen = function (response) {
ws.send('message!');
conversation.append(createSpan('Azure CONNECTED'));
}
ws.onerror = function (e) {
conversation.append(createSpan("There are connection issues"));
}
}
else {
alert("Your browser does not support instant messaging. You need to regularly refresh your browser in order to receive updates");
}
}
I have enabled using Websockets in Azure Portal
Enabling using Websockets in Azure Portal
Thanks for your ideas!

Related

Unable able to communicate between two services

I have created two Web API in Asp.net Core one is Wrapper Service to be deployed on DMZ Server and other is core service which have access to our DB Non DMZ. The problem i am facing is that i am unable to communicate between two services.
Both are running on local machine through dockers. When i try to hit core service running on url: https://localhost:56788/Rewards thorugh HttpClient/WebRequest i got message
No connection could be made because the target machine actively refused it.
DMZ Controller Logic
[Route("[controller]")]
[ApiController]
public class RewardsController : ControllerBase
{
[HttpGet]
public string Get()
{
string response = string.Empty;
//using (var client = new HttpClient())
//{
// client.BaseAddress = new Uri("http://localhost:5000/");
// //HTTP GET
// var responseTask = client.GetAsync("Rewards");
// responseTask.Wait();
// var result = responseTask.Result;
// if (result.IsSuccessStatusCode)
// {
// response = result.ToString();
// }
// else //web api sent error response
// {
// //log response status here..
// response = "Error";
// }
//}
string sURL = "https://localhost:56788/Rewards";
WebRequest wrPostURL = WebRequest.Create(sURL);
wrPostURL.Method = "GET";
ServicePointManager.ServerCertificateValidationCallback += (sender, cert, chain, sslPolicyErrors) => true;
using (HttpWebResponse webresponse = wrPostURL.GetResponse() as HttpWebResponse)
{
Encoding enc = System.Text.Encoding.GetEncoding("utf-8");
StreamReader loResponseStream = new StreamReader(webresponse.GetResponseStream(), enc);
var jsonResponse = loResponseStream.ReadToEnd();
loResponseStream.Close();
webresponse.Close();
}
return response;
}
}
NON-DMZ Controller Logic
[Route("[controller]")]
[ApiController]
public class RewardsController : ControllerBase
{
[HttpGet]
public string Get()
{
return "Hello";
}
}
Update
This problem is due to dockers. When i deploy both APIs to IIS then it will work fine but i have to do it with Dockers
The problem occurs due to the fact that i was calling localhost to communicate with other API running on another container. When we call localhost the first container start looking for the service that is running on same container. By using VM/Local Machine IP instead of localhost the problem can be avoided.

Signup user to ASP.NET Identity from Xamarin

I have been stuck all day on a stupid problem with registering a user to my application.
Here is my code once the 'Register' button is clicked:
public ICommand RegisterCommand
{
get
{
return new Command(async() =>
{
var isSuccess = await _apiServices.RegisterAsync(Email, Password, ConfirmPassword);
if (isSuccess){
Message = "Registered Successfully";
}
else
{
Message = "Retry later";
}
});
}
}
Api services Register Async method:
public async Task<bool> RegisterAsync(string email, string password, string confirmPassword)
{
try
{
System.Diagnostics.Debug.WriteLine("Email: "+email);
var client = new HttpClient();
var model = new RegisterBindingModel
{
Email = email,
Password = password,
ConfirmPassword = confirmPassword
};
var json = JsonConvert.SerializeObject(model);
HttpContent content = new StringContent(json);
// content.Headers.ContentType = new MediaTypeHeaderValue("application/json");
content.Headers.ContentType = new MediaTypeHeaderValue("application/json");
var response = await client.PostAsync("http://localhost:63724/api/Account/Register", content);
if (response.IsSuccessStatusCode)
{
return true;
}
return false;
}
catch (Exception e)
{
System.Diagnostics.Debug.WriteLine("Error: "+e);
throw;
}
}
}
The Error that I get is:
System.Net.Http.HttpRequestException: An error occurred while sending the request ---> System.Net.WebException: Error: ConnectFailure (Connection refused) ---> System.Net.Sockets.SocketException: Connection refused
at System.Net.Sockets.Socket.Connect (System.Net.EndPoint remoteEP) [0x000b6] in <6c708cf596db438ebfc6b7e012659eee>:0
at System.Net.WebConnection.Connect (System.Net.HttpWebRequest request) [0x0016d] in <6c708cf596db438ebfc6b7e012659eee>:0
--- End of inner exception stack trace ---
To me this is very frustrating as I can register a use using Postman with the exact same localhost address. I am following Houssem Dellai's Xamarin.Forms mvc web api tutorials which can be found here
I had an issue with httpclient during the development of my app. I believe there was an issue with the cross-platform implementation of the httpclient class. iOS didn't know how to handle it.
Instead I implemented a very simple httpclient library called flurl: http://tmenier.github.io/Flurl/
First, you will need to install flurl in all project directories (iOS, Android, and the PCL) then the implementation is very simple.
using Flurl;
using Flurl.Http;
public async Task<User> CreateUserAsync(RegisterUserModel userModel)
{
string url = "your/backend/here";
//resp is a user object received and automatically converted into a c# object through the use of .ReceiveJson<typeofobject>();
var resp = await (url).PostJsonAsync(userModel)
.ReceiveJson<User>();
if (resp.LoginSession != null)
{
//Raise my registered event to let other classes know to proceed
OnUserRegistered(resp);
}
return resp;
}
As you can see it makes httpclient implementation very simple. Hopefully this helps.

Enabling Cross Origin Requests for WebSockets in Spring

I have a OpenShift Wildfly server. I am building a website with the Spring MVC framework. One of my webpages also uses a WebSocket connection. On the server side, I have used the #ServerEndpoint annotation and javax.websocket.* library to create my websocket:
package com.myapp.spring.web.controller;
import java.io.IOException;
import javax.websocket.OnClose;
import javax.websocket.OnError;
import javax.websocket.OnMessage;
import javax.websocket.OnOpen;
import javax.websocket.Session;
import javax.websocket.server.ServerEndpoint;
import org.springframework.web.socket.server.standard.SpringConfigurator;
#ServerEndpoint(value="/serverendpoint", configurator = SpringConfigurator.class)
public class serverendpoint {
#OnOpen
public void handleOpen () {
System.out.println("JAVA: Client is now connected...");
}
#OnMessage
public String handleMessage (Session session, String message) throws IOException {
if (message.equals("ping")) {
// return "pong"
session.getBasicRemote().sendText("pong");
}
else if (message.equals("close")) {
handleClose();
return null;
}
System.out.println("JAVA: Received from client: "+ message);
MyClass mc = new MyClass(message);
String res = mc.action();
session.getBasicRemote().sendText(res);
return res;
}
#OnClose
public void handleClose() {
System.out.println("JAVA: Client is now disconnected...");
}
#OnError
public void handleError (Throwable t) {
t.printStackTrace();
}
}
OpenShift gives a default URL, so all of my webpages (html files) have the common (canonical) hostname. For the sake of simplicity, I am calling this URL URL A (projectname-domainname.rhclound.com). I created an alias, CNAME, of URL A, which is called URL B (say https://www.mywebsite.tech). URL B is secure, as it has the https.
I am using a JavaScript client to connect to the WebSocket at the path /serverendpoint. The URI I am using in my html webpage file, test.html, is the following:
var wsUri = "wss://" + "projectname-domainname.rhclound.com" + ":8443" + "/serverendpoint";
When I open up URL A (projectname-domainname.rhclound.com/test), the WebSocket connects and everything works fine. However, when I try to connect to the websocket using URL B (https://mywebsite.tech/test), the JavaScript client immediately connects and disconnects.
Here is the message from the console that I receive:
Here is my JavaScript code that connects to the WebSocket:
/****** BEGIN WEBSOCKET ******/
var connectedToWebSocket = false;
var responseMessage = '';
var webSocket = null;
function initWS() {
connectedToWebSocket = false;
var wsUri = "wss://" + "projectname-domainname.rhcloud.com" + ":8443" + "/serverendpoint";
webSocket = new WebSocket(wsUri); // Create a new instance of WebSocket using usUri
webSocket.onopen = function(message) {
processOpen(message);
};
webSocket.onmessage = function(message) {
responseMessage = message.data;
if (responseMessage !== "pong") { // Ping-pong messages to keep a persistent connection between server and client
processResponse(responseMessage);
}
return false;
};
webSocket.onclose = function(message) {
processClose(message);
};
webSocket.onerror = function(message) {
processError(message);
};
console.log("Exiting initWS()");
}
initWS(); //Connect to websocket
function processOpen(message) {
connectedToWebSocket = true;
console.log("JS: Server Connected..."+message);
}
function sendMessage(toServer) { // Send message to server
if (toServer != "close") {
webSocket.send(toServer);
} else {
webSocket.close();
}
}
function processClose(message) {
connectedToWebSocket = false;
console.log("JS: Client disconnected..."+message);
}
function processError(message) {
userInfo("An error occurred. Please contact for assistance", true, true);
}
setInterval(function() {
if (connectedToWebSocket) {
webSocket.send("ping");
}
}, 4000); // Send ping-pong message to server
/****** END WEBSOCKET ******/
After a lot of debugging and trying various things, I concluded that this was problem was occurring because of the Spring Framework. This is because before I introduced the Spring Framework in my project, URL B could connect to the WebSocket, but after introducing Spring, it cannot.
I read on spring's website about WebSocket Policy. I came across their same origin policy which states that an alias, URL B, cannot connect to the WebSocket because it is not the same origin as URL A is. To solve this problem I disabled the same origin policy with WebSockets as said in the documentation, so I added the following code. I thought that doing so would fix my error. Here is what I added:
import org.springframework.context.annotation.Configuration;
import org.springframework.security.config.annotation.web.socket.AbstractSecurityWebSocketMessageBrokerConfigurer;
#Configuration
public class WebSocketSecurityConfig extends AbstractSecurityWebSocketMessageBrokerConfigurer {
#Override
protected boolean sameOriginDisabled() {
return true;
}
}
However, this did not fix the problem, so I added the following method to my ApplicationConfig which extends WebMvcConfigurerAdapter:
#Override
public void addCorsMappings(CorsRegistry registry) {
registry.addMapping("/**").allowedOrigins("https://www.mywebsite.com");
}
This also didn't work either. Then I tried this:
package com.myapp.spring.security.config;
import org.springframework.boot.web.servlet.FilterRegistrationBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.cors.CorsConfiguration;
import org.springframework.web.cors.UrlBasedCorsConfigurationSource;
import org.springframework.web.filter.CorsFilter;
#Configuration
public class MyCorsFilter {
// #Bean
// public FilterRegistrationBean corsFilter() {
// System.out.println("Filchain");
// UrlBasedCorsConfigurationSource source = new UrlBasedCorsConfigurationSource();
// CorsConfiguration config = new CorsConfiguration();
// config.setAllowCredentials(true);
// config.addAllowedOrigin("https://www.mymt.tech");
// config.addAllowedHeader("*");
// config.addAllowedMethod("*");
// source.registerCorsConfiguration("/**", config);
// FilterRegistrationBean bean = new FilterRegistrationBean(new CorsFilter(source));
// bean.setOrder(0);
// System.out.println("Filchain");
// return bean;
// }
#Bean
public CorsFilter corsFilter() {
System.out.println("Filchain");
UrlBasedCorsConfigurationSource source = new UrlBasedCorsConfigurationSource();
CorsConfiguration config = new CorsConfiguration();
config.setAllowCredentials(true); // you USUALLY want this
config.addAllowedOrigin("*");
config.addAllowedHeader("*");
config.addAllowedMethod("*");
config.addAllowedMethod("*");
source.registerCorsConfiguration("/**", config);
System.out.println("Filchain");
return new CorsFilter(source);
}
}
This also did not work.
I even changed the var wsURI in the JS code to the following:
var wsUri = "wss://" + "www.mywebsite.com" + ":8443" + "/serverendpoint";
Then var wsUri = "wss://" + "mywebsite.com" + ":8443" + "/serverendpoint";
When I did this, the Google Chrome gave me an error, saying that the handshake failed. However, when I have this URL, var wsUri = "wss://" + "projectname-domianname.rhcloud.com" + ":8443" + "/serverendpoint";, I did not get the error that the handshake didn't occur, but I get a message that the connection opened and closed immediately (as seen above).
So how can I fix this?
Have you tried implementing the WebMvcConfigurer and overriding the method addCorsMappings()? If not try this and see.
#EnableWebMvc
#Configuration
#ComponentScan
public class WebConfig implements WebMvcConfigurer {
#Override
public void addCorsMappings(CorsRegistry registry) {
registry.addMapping("/**")
.allowedOrigins("*")
.allowedMethods("GET", "POST")
.allowedHeaders("Origin", "Accept", "Content-Type", "Authorization")
.allowCredentials(true)
.maxAge(3600);
}
}
I don't think it's a CORS issue because it's connected successully before being disconnected. If that's CORS, you can't even connect.
I think it's a communication problem between your DNS & openshift because WebSocket need a persistent connection (long-live) which keeps opening between client & server. If your DNS (e.g. CloudFlare or something like that) does not support / not configured to use WebSocket, the client would be disconnected immediately as in your issue.

"Could not establish trust relationship for the SSL/TLS secure channel." Exception on signalr2.2, https, .net client, custom certificate

I got some exception in testing signalr .net client with custom self-signed certificate.
There was no exception on http.
Is there any problem in setting up the self-signed certificate in my code?
Note that, there is no problem in my certificate file because it runs my https mvc sites well.
server side code : asp.net, azure local fabric
[assembly: OwinStartup(typeof(BookohWebRole.Startup))]
namespace BookohWebRole
{
public class Startup
{
public void Configuration(IAppBuilder app)
{
var hubConfiguration = new HubConfiguration();
hubConfiguration.EnableDetailedErrors = true;
hubConfiguration.EnableJavaScriptProxies = false;
//GlobalHost.HubPipeline.AddModule(new ErrorHandlingPipelineModule());
app.MapSignalR(hubConfiguration);
}
}
}
public class ChatHub : Hub
{
public override Task OnConnected()
{
Trace.TraceInformation("OnConnected");
var authToken = Context.QueryString.Get("AuthToken");
Trace.TraceInformation("authToken : " + authToken);
return base.OnConnected();
}
public override Task OnDisconnected(bool stopCalled)
{
Trace.TraceInformation("OnDisconnected");
return base.OnDisconnected(stopCalled);
}
public override Task OnReconnected()
{
Trace.TraceInformation("OnReconnected");
var authToken = Context.QueryString.Get("AuthToken");
Trace.TraceInformation("authToken : " + authToken);
return base.OnReconnected();
}
public void Send(string name, string message)
{
Trace.TraceInformation("Context.ConnectionId : " + Context.ConnectionId);
Clients.All.onSend(name, message);
}
}
client side code : .net client, unit test method
[TestMethod]
public void chat()
{
var ev = new AutoResetEvent(false);
Task.Run(async () =>
{
try
{
ServicePointManager.DefaultConnectionLimit = 10;
var queryString = new Dictionary<string, string>();
queryString.Add("AuthToken", Guid.NewGuid().ToString());
//https://localhost:44302/
//http://localhost:22792/
var hubConnection = new HubConnection("https://localhost:44302/");
hubConnection.Credentials = CredentialCache.DefaultCredentials;
hubConnection.AddClientCertificate(X509Certificate.CreateFromCertFile("bookoh.cer"));
hubConnection.TraceLevel = TraceLevels.All;
hubConnection.TraceWriter = Console.Out;
IHubProxy chatHubProxy = hubConnection.CreateHubProxy("ChatHub");
await hubConnection.Start();
chatHubProxy.On<string, string>("onSend", (name, message) =>
{
Trace.TraceInformation("onSend name : " + name);
Trace.TraceInformation("onSend message : " + message);
ev.Set();
});
Trace.TraceInformation("chatHubProxy.Invoke");
await chatHubProxy.Invoke("Send", "hhd2002", "hello");
}
catch (Exception ex)
{
Trace.TraceInformation("ex : " + ex);
}
});
ev.WaitOne();
}
full exception message on client program
vstest.executionengine.x86.exe Information: 0 : ex : System.Net.Http.HttpRequestException: An error occurred while sending the request. ---> System.Net.WebException: The underlying connection was closed: Could not establish trust relationship for the SSL/TLS secure channel. ---> System.Security.Authentication.AuthenticationException: The remote certificate is invalid according to the validation procedure.
at System.Net.TlsStream.EndWrite(IAsyncResult asyncResult)
at System.Net.PooledStream.EndWrite(IAsyncResult asyncResult)
at System.Net.ConnectStream.WriteHeadersCallback(IAsyncResult ar)
It looks like your actual exception message is
The remote certificate is invalid according to the validation procedure.
This is most likely due to it being self-signed and not signed by a trusted certificate authority. It looks like this has already been answered here:
C# Ignore certificate errors?
I had this issue and it was due to an expired/missing Digi Cert Global Root G2 certificate.
I believe if you raise it with Microsoft they provide you a new certificate, however I just applied it from another machine.
The underlying connection was closed: Could not establish trust relationship for the SSL/TLS secure channel

Call specific clients in SignalR

I'm developing a SignalR application in which set of .NET console clients connecting to a web server. How can I call a specific client from the server using SignalR.
In the current application I did, when I click button from the server side. It triggers all the Console clients. But what I want to trigger is keeping all client information on server.html and call specific client.
Currently this is my console application
class Program
{
static void Main(string[] args)
{
var connection = new Connection("http://localhost:65145/printer");
//Establishing the connection
connection.Start().ContinueWith(task =>
{
if (task.IsFaulted)
{
Console.WriteLine("Failed to start: {0}", task.Exception.GetBaseException());
}
else
{
Console.WriteLine("Success! Connected with client connection id {0}", connection.ConnectionId);
}
});
//Reciveing data from the server
connection.Received += data =>
{
Console.WriteLine("Receiving print request from server");
Console.WriteLine(data);
};
Console.ReadLine();
}
}
This is the server side.
server html which calls clients
<script type="text/javascript">
$(function () {
var connection = $.connection('/printer');
connection.received(function (data) {
//$('#messages').append('<li>' + data + '</li>');
});
connection.start().done(function() {
$('#print').click(function () {
var printThis = { value: 113, reportId: 'Report', printer: '3rd Floor Lazer Printer', Copies: 1 };
connection.send(JSON.stringify(printThis));
});
});
});
</script>
Global.asax
protected void Application_Start(object sender, EventArgs e)
{
RouteTable.Routes.MapHubs();
RouteTable.Routes.MapConnection<MyConnection>("printer", "/printer");
}
The documentation shows how to do this https://github.com/SignalR/SignalR/wiki/PersistentConnection#sending-to-a-specific-connection

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