Xbase++

WebSocket Connect

See more WebSocket Examples

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.) Xbase++

LOCAL nSuccess
LOCAL oRest
LOCAL oWs
LOCAL cResponseBody
LOCAL nStatusCode

nSuccess := 0

//  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.
//  

oRest := CreateObject("Chilkat.Rest")
nSuccess := oRest:Connect("someserver.com", 80, 0, 0)
IF (nSuccess != 1)
    ? oRest:LastErrorText
    oRest:destroy()
    RETURN
ENDIF

oWs := CreateObject("Chilkat.WebSocket")

//  Tell the WebSocket to use this connection.
nSuccess := oWs:UseConnection(oRest)
IF (nSuccess != 1)
    ? oWs:LastErrorText
    oRest:destroy()
    oWs:destroy()
    RETURN
ENDIF

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

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

//  Do the open handshake.
cResponseBody := oRest:FullRequestNoBody("GET", "/something")
IF (oRest:LastMethodSuccess != 1)
    ? oRest:LastErrorText
    oRest:destroy()
    oWs:destroy()
    RETURN
ENDIF

//  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..)
nStatusCode := oRest:ResponseStatusCode
? "Response status code: " + Str(nStatusCode)

IF (nStatusCode != 101)
    ? cResponseBody
    ? "-- Failed because of unexpected response status code."
    oRest:destroy()
    oWs:destroy()
    RETURN
ENDIF

//  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. 
nSuccess := oWs:ValidateServerHandshake()
IF (nSuccess != 1)
    ? oWs:LastErrorText
    oRest:destroy()
    oWs:destroy()
    RETURN
ENDIF

? "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...)

oRest:destroy()
oWs:destroy()