(Excel) WebSocket Connect

Demonstrates how to establish a WebSocket connection. Once the connection is established, messages may be sent back-and-forth. Messages are sent in frames, where the last frame in the message is indicated by a "final" bit. A frame constitutes the entire message if the first frame sent has the "final" bit sent. (In most cases, you'll probably be sending single-frame messages.)

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'  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 Chilkat.Rest
Set rest = Chilkat.NewRest

success = rest.Connect("someserver.com",80,False,False)
If (success <> True) Then
    Debug.Print rest.LastErrorText
    Exit Sub
End If

Dim ws As Chilkat.WebSocket
Set ws = Chilkat.NewWebSocket

'  Tell the WebSocket to use this connection.
success = ws.UseConnection(rest)
If (success <> True) Then
    Debug.Print 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.)
success = ws.AddClientHeaders()

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

'  Do the open handshake.

responseBody = rest.FullRequestNoBody("GET","/something")
If (rest.LastMethodSuccess <> True) Then
    Debug.Print 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..)

statusCode = rest.ResponseStatusCode
Debug.Print "Response status code: "; statusCode

If (statusCode <> 101) Then
    Debug.Print responseBody
    Debug.Print "-- 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.Print ws.LastErrorText
    Exit Sub
End If

Debug.Print "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...)