(Lianja) 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.

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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.
// 

loRest = createobject("CkRest")
//  ------------------------------------------------------------------
//  To use TLS, connect to the TLS port (typically 443) and tell the rest.Connect method
//  that it's a TLS connection.
//  ------------------------------------------------------------------
llBUseTls = .T.
llSuccess = loRest.Connect("someserver.com",443,llBUseTls,.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