Lianja

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.) Lianja

llSuccess = .F.

// 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.
// 

loRest = createobject("CkRest")
llSuccess = loRest.Connect("someserver.com",80,.F.,.F.)
if (llSuccess <> .T.) then
    ? loRest.LastErrorText
    release loRest
    return
endif

loWs = createobject("CkWebSocket")

// Tell the WebSocket to use this connection.
llSuccess = loWs.UseConnection(loRest)
if (llSuccess <> .T.) then
    ? loWs.LastErrorText
    release loRest
    release loWs
    return
endif

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

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

// Do the open handshake.
lcResponseBody = loRest.FullRequestNoBody("GET","/something")
if (loRest.LastMethodSuccess <> .T.) then
    ? loRest.LastErrorText
    release loRest
    release loWs
    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..)
lnStatusCode = loRest.ResponseStatusCode
? "Response status code: " + str(lnStatusCode)

if (lnStatusCode <> 101) then
    ? lcResponseBody
    ? "-- Failed because of unexpected response status code."
    release loRest
    release loWs
    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. 
llSuccess = loWs.ValidateServerHandshake()
if (llSuccess <> .T.) then
    ? loWs.LastErrorText
    release loRest
    release loWs
    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...)


release loRest
release loWs