How to send Mattermost authentication headers to check whether the socket is connected successfully?

I need to check whether the socket connection established successfully. In order to verify that how to send the following mattermost authentication header over the connection?
{
"seq": 1,
"action": "authentication_challenge",
"data": {
"token": "mattermosttokengoeshere"
}
}

Can you please refer me any tutorial to refer this. How can I verify that the socket is connected successfully in my project.

[gaming-hacker]

did you get the echoTest to work?