(VB.NET UWP/WinRT) WebSocket over TLS

Establishing a WebSocket connection over TLS is exactly the same as for TCP, except for a few arguments passed to the Connect method.

Chilkat Universal Windows Platform (UWP) / WinRT Downloads Chilkat for the Universal Windows Platform (UWP)

'  This example requires the Chilkat API to have been previously unlocked.
'  See Global Unlock Sample for sample code.


'  --------------------------------------------------
'  A WebSocket connection begins life as an HTTP GET request containing a few special header fields,
'  such as "Upgrade: websocket".

'  Your application will use the Chilkat Rest class to send the initial HTTP GET.  This allows you
'  to use the full capability of the Chilkat Rest class to customize the GET for any particular situation.
'  For example:
' 
'    - If custom HTTP request header fields must be added.
'    - If authentication is required, such as OAuth2, OAuth1, Basic HTTP Auth, etc.
'    - If HTTPS, SSH Tunneling, Proxies (HTTP or SOCKS), or other advanced connection or TLS features are required.
' 

Dim rest As New Chilkat.Rest
'  ------------------------------------------------------------------
'  To use TLS, connect to the TLS port (typically 443) and tell the rest.Connect method
'  that it's a TLS connection.
'  ------------------------------------------------------------------
Dim bUseTls As Boolean = True
Dim success As Boolean = Await rest.ConnectAsync("someserver.com",443,bUseTls,False)
If (success <> True) Then
    Debug.WriteLine(rest.LastErrorText)
    Exit Sub
End If


Dim ws As New Chilkat.WebSocket

'  Tell the WebSocket to use this connection.
success = ws.UseConnection(rest)
If (success <> True) Then
    Debug.WriteLine(ws.LastErrorText)
    Exit Sub
End If


'  Add the standard WebSocket open handshake headers that will be needed.
'  (This adds the required HTTP request headers to the rest object.)
ws.AddClientHeaders()

'  Add any additional headers that might be desired.
'  Two common WebSocketSpecific headers are "Sec-WebSocket-Protocol" and "Origin".
rest.AddHeader("Sec-WebSocket-Protocol","x-something")
rest.AddHeader("Origin","http://someserver.com")

'  Do the open handshake.
Dim responseBody As String = Await rest.FullRequestNoBodyAsync("GET","/something")
If (rest.LastMethodSuccess <> True) Then
    Debug.WriteLine(rest.LastErrorText)
    Exit Sub
End If


'  If successful, the HTTP response status code should be 101,
'  and the response body will be empty. (If it failed, we'll have a look
'  at the response body..)
Dim statusCode As Integer = rest.ResponseStatusCode
Debug.WriteLine("Response status code: " & statusCode)

If (statusCode <> 101) Then
    Debug.WriteLine(responseBody)
    Debug.WriteLine("-- Failed because of unexpected response status code.")
    Exit Sub
End If


'  We have the expected 101 response, so let's now validate the
'  contents of the response, such as the value sent by the server in the
'  Sec-WebSocket-Accept header.
success = ws.ValidateServerHandshake()
If (success <> True) Then
    Debug.WriteLine(ws.LastErrorText)
    Exit Sub
End If


Debug.WriteLine("WebSocket connection successful.")

'  The application may now begin sending and receiving frames on the WebSocket connection.
'  (At this point, we're done with the rest object...)