private_port

[SamuelHenriqueDeMoraisVitrio]

if props.port then

    selfobj.private.url = "http://127.0.0.1:"..selfobj.private.port
    local command = "%s --port=%d &"
    command = command:format(props.chromedriver_command, props.port)
    print("Starting chromedriver with command: " .. command)
    local ok = os.execute(command)
    if ok then
        error("Failed to start chromedriver with command: " .. command)
    end    
else

Nesse private.port deveria inicialmente receber o valor de props.port