Connecting to Qlik sense Server using .NET SDK

[#1]

Hi,

I am using qlik sense server version 2.1.1 and have .net sdk version also 2.1.1. I am trying to build a windows forms application which simply displays the server version. When I run the code, it gives me an error "unable to keep connection opened".

I am attaching the screenshot of error and below is my code.

     private void Form1_Load(object sender, EventArgs e)

        {          

            Uri uri = new Uri("https://abdullah-pc:4747");  // abdullah-pc is my server machine

            ILocation location = Qlik.Engine.Location.FromUri(uri);

            location.AsNtlmUserViaProxy();

            using (IHub hub = location.Hub())

            {

                label1.Text = hub.ProductVersion();

            }

        }

If anyone helps, I'll be thankful.

AbdulRahman

[Øystein_Kolsrud]

Do you use virtual proxies? You might have to do a proxy setting on the location object. Something like this:

location.VirtualProxyPath = "myproxypath"

[#3]

Hi Kolsrud,

Thanks for your quick reply. Actually I have installed sense server locally on my laptop. And I haven't configured any virtual proxy in it. but default virtual proxy set to Central is already setup. Attaching the screenshot.

One thing more, I use to give username, password each time when want to access qmc or hub. Also attaching the screenshot of that. may be it could be helpful resolving my issue. Also, I have added my machine name "Abdullah-PC"  to web socket whitelist in virtual proxy.

Thanks

[konrad_mattheis]

Hi Abdul,

I think you use the wrong uri:

just remove the :4747

Uri uri = new Uri("https://abdullah-pc/);  // abdullah-pc is my server machine

bye

Konrad

[#5]

Hello Konard,

I have tried that all things. like  ws://localhost:4848,  https://abdullah-pc:4244, https://localhost:4848, https://abdullah-pc.  But same error popping out

AbdulRahman

[konrad_mattheis]

Hi Abdul,

it should work. I do the same with no problems. Please go through that checklist:

1. Qlik Sense Server on your PC Version 2.1.1

2. If you open Qlik Sense in "Internet Explorer" you can connect without any ssl error

3. please try just:

       using (var db= new DebugConsole())

            {

           location = Qlik.Engine.Location.FromUri(new URI("https://abdullah-pc"));

          location.AsNtlmUserViaProxy(ssl);

       using (IHub hub = location.Hub())

            {

                label1.Text = hub.ProductVersion();

            }

     }

Please also add Screenshots and the output in the Console.

thx Konrad

[#7]

Thanks Konard for your help. I am able to open qlik sense in IE 11. Also I have used DebugConsole() function and got a complete error trace. Attaching the text file of error description.

[#8]

Sorry Konard,

I was unable to attach file. I am writing here the error log from console. ! !

### WebSocket Error: Object reference not set to an instance of an object. ### 43927528

### WebSocket Stack Trace: 43927528

   at Qlik.Sense.Communication.Communication.Tcp.StreamFactory.NegotiateAsClient(ITcpClientWrapper tcpClient, Uri remoteUri, SslConnection sslConnection, Action`1 onComplete, Action`1 onError)

   at Qlik.Sense.Communication.Communication.WebSocketProtocol.WebSocketHandler.<>c__DisplayClass6.<NewClientWebSocketAsync>b__4(ITcpClientWrapper client)

   at Qlik.Sense.Communication.Communication.Tcp.TcpClientWrapperFactory`1.<>c__DisplayClass5.<NewAndConnectedTcpClient>b__4(IAsyncResult result)

### Failed to ensure open connection ### 43927528

### Failed attempt 1 ### 43927528

### Failure message: Failed to ensure open connection: One or more errors occurred.

### WebSocket Error: Object reference not set to an instance of an object. ### 43927528

### WebSocket Stack Trace: 43927528

   at Qlik.Sense.Communication.Communication.Tcp.StreamFactory.NegotiateAsClient(ITcpClientWrapper tcpClient, Uri remoteUri, SslConnection sslConnection, Action`1 onComplete, Action`1 onError)

   at Qlik.Sense.Communication.Communication.WebSocketProtocol.WebSocketHandler.<>c__DisplayClass6.<NewClientWebSocketAsync>b__4(ITcpClientWrapper client)

   at Qlik.Sense.Communication.Communication.Tcp.TcpClientWrapperFactory`1.<>c__DisplayClass5.<NewAndConnectedTcpClient>b__4(IAsyncResult result)

### Failed to ensure open connection ### 43927528

### Failed attempt 2 ### 43927528

### Failure message: Failed to ensure open connection: One or more errors occurred.

### WebSocket Error: Object reference not set to an instance of an object. ### 43927528

### WebSocket Stack Trace: 43927528

   at Qlik.Sense.Communication.Communication.Tcp.StreamFactory.NegotiateAsClient(ITcpClientWrapper tcpClient, Uri remoteUri, SslConnection sslConnection, Action`1 onComplete, Action`1 onError)

   at Qlik.Sense.Communication.Communication.WebSocketProtocol.WebSocketHandler.<>c__DisplayClass6.<NewClientWebSocketAsync>b__4(ITcpClientWrapper client)

   at Qlik.Sense.Communication.Communication.Tcp.TcpClientWrapperFactory`1.<>c__DisplayClass5.<NewAndConnectedTcpClient>b__4(IAsyncResult result)

### Failed to ensure open connection ### 43927528

### Failed attempt 3 ### 43927528

### Failure message: Failed to ensure open connection: One or more errors occurred.

### WebSocket Error: Object reference not set to an instance of an object. ### 43927528

### WebSocket Stack Trace: 43927528

   at Qlik.Sense.Communication.Communication.Tcp.StreamFactory.NegotiateAsClient(ITcpClientWrapper tcpA first chance exception of type 'Qlik.Engine.Communication.CommunicationErrorException' occurred in Qlik.Engine.dll

Client, Uri remoteUri, SslConnection sslConnection, Action`1 onComplete, Action`1 onError)

   at Qlik.Sense.Communication.Communication.WebSocketProtocol.WebSocketHandler.<>c__DisplayClass6.<NewClientWebSocketAsync>b__4(ITcpClientWrapper client)

   at Qlik.Sense.Communication.Communication.Tcp.TcpClientWrapperFactory`1.<>c__DisplayClass5.<NewAndConnectedTcpClient>b__4(IAsyncResult result)

### Failed to ensure open connection ### 43927528

### WebSocket Error: Connection failed after 4 attempts. Unable to keep connection open: Failed to ensure open connection: One or more errors occurred. ### 43927528

[Øystein_Kolsrud]

Sounds like your Qlik Sense server is not set configured to utilize your windows credentials. You might want to look into the settings your QMC. For instance, have a look at the "User Directory Connectors" under "Manage Resources" and check that the relevant user directory is included there.

[Øystein_Kolsrud]

Since your server is running locally, it could also be possible for you to do a direct connection to it. So instead of doing "AsNtlmUserViaProxy" you would do "AsDirectConnection" like this:

location.AsDirectConnection(<your user directory name>, <your user id>);

But if you want to be able to use your application so that it can connect to non-local servers, then this is probably not your long term solution.