SQL Server

Duplicate Python websockets

See more WebSocket Examples

Demonstrates how to duplicate the following Python client-side websocket snippet:

async with websockets.connect('ws://192.168.1.35/websocket') as websocket:
await websocket.send("http.controller_login:username=xxx&password=xxxxx")
response = await websocket.recv()

SQL Server

-- Important: See this note about string length limitations for strings returned by sp_OAMethod calls.
--
CREATE PROCEDURE ChilkatSample
AS
BEGIN
    DECLARE @hr int
    DECLARE @iTmp0 int
    -- Important: Do not use nvarchar(max).  See the warning about using nvarchar(max).
    DECLARE @sTmp0 nvarchar(4000)
    DECLARE @success int
    SELECT @success = 0

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

    -- In Python, the following line of code does more than just connect:
    -- 
    --      websockets.connect('ws://192.168.1.35/websocket')
    -- 
    -- It is connecting to 192.168.1.35 without using TLS.  If the URI starts with "wss://", then TLS should be used.
    -- But this URI begins with just "ws:/", so no TLS.

    -- Also, after connecting, a GET request is sent to the /websocket endpoint.
    -- In summary, the websockets.connect function is establishing the connection and it sends a GET request.

    -- First establish the connection.
    -- No TLS, use the default HTTP port 80.
    DECLARE @rest int
    EXEC @hr = sp_OACreate 'Chilkat.Rest', @rest OUT
    IF @hr <> 0
    BEGIN
        PRINT 'Failed to create ActiveX component'
        RETURN
    END

    EXEC sp_OAMethod @rest, 'Connect', @success OUT, '192.168.1.35', 80, 0, 0
    IF @success <> 1
      BEGIN
        EXEC sp_OAGetProperty @rest, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @rest
        RETURN
      END

    DECLARE @ws int
    EXEC @hr = sp_OACreate 'Chilkat.WebSocket', @ws OUT

    -- Tell the WebSocket to use this connection.
    EXEC sp_OAMethod @ws, 'UseConnection', @success OUT, @rest
    IF @success <> 1
      BEGIN
        EXEC sp_OAGetProperty @ws, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @rest
        EXEC @hr = sp_OADestroy @ws
        RETURN
      END

    -- Add the standard WebSocket open handshake headers that will be needed.
    -- (This adds the required HTTP request headers to the rest object.)
    EXEC sp_OAMethod @ws, 'AddClientHeaders', @success OUT

    -- Now send the GET request to /websockets.
    DECLARE @responseBody nvarchar(4000)
    EXEC sp_OAMethod @rest, 'FullRequestNoBody', @responseBody OUT, 'GET', '/websockets'
    EXEC sp_OAGetProperty @rest, 'LastMethodSuccess', @iTmp0 OUT
    IF @iTmp0 <> 1
      BEGIN
        EXEC sp_OAGetProperty @rest, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @rest
        EXEC @hr = sp_OADestroy @ws
        RETURN
      END

    -- 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..)
    DECLARE @statusCode int
    EXEC sp_OAGetProperty @rest, 'ResponseStatusCode', @statusCode OUT

    PRINT 'Response status code: ' + @statusCode

    IF @statusCode <> 101
      BEGIN

        PRINT @responseBody

        PRINT '-- Failed because of unexpected response status code.'
        EXEC @hr = sp_OADestroy @rest
        EXEC @hr = sp_OADestroy @ws
        RETURN
      END

    -- We have the expected 101 response, so let's now validate the 
    -- contents of the response.
    EXEC sp_OAMethod @ws, 'ValidateServerHandshake', @success OUT
    IF @success <> 1
      BEGIN
        EXEC sp_OAGetProperty @ws, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @rest
        EXEC @hr = sp_OADestroy @ws
        RETURN
      END


    PRINT 'WebSocket connection successful.'

    -- The application may now begin sending and receiving frames on the WebSocket connection.

    -- The 1st frame sent by the Python snippet is:
    -- 
    --     websocket.send("http.controller_login:username=xxx&password=xxxxx")
    -- 

    -- Send the same using Chilkat, and get the response.
    DECLARE @finalFrame int
    SELECT @finalFrame = 1
    EXEC sp_OAMethod @ws, 'SendFrame', @success OUT, 'http.controller_login:username=xxx&password=xxxxx', @finalFrame
    IF @success <> 1
      BEGIN
        EXEC sp_OAGetProperty @ws, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @rest
        EXEC @hr = sp_OADestroy @ws
        RETURN
      END

    -- Read an incoming frame.
    EXEC sp_OAMethod @ws, 'ReadFrame', @success OUT
    IF @success <> 1
      BEGIN

        PRINT 'Failed to receive a frame'

        EXEC sp_OAGetProperty @ws, 'ReadFrameFailReason', @iTmp0 OUT
        PRINT 'ReadFrame fail reason = ' + @iTmp0
        EXEC sp_OAGetProperty @ws, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @rest
        EXEC @hr = sp_OADestroy @ws
        RETURN
      END

    -- Show the string that was received.
    DECLARE @receivedStr nvarchar(4000)
    EXEC sp_OAMethod @ws, 'GetFrameData', @receivedStr OUT

    PRINT 'Received: ' + @receivedStr

    -- Continue with whatever additional communications are desired...
    -- ....
    -- 

    EXEC @hr = sp_OADestroy @rest
    EXEC @hr = sp_OADestroy @ws


END
GO