Function cgiGet()

Execute HTTP GET call to given url and read the response. The call is asynchronous: the code execution proceeds immediately and when the response arrives, callback function is called. To perform simple HTTP GET call without response handling, use simpler devices.system.CustomCGI()

nil devices.system.cgiGet{config}

Parameters

table config{url, callback, timeout, bufferSize}

• string url address to call
• function{response} callback this function is called when response arrives
• optional number timeout maximum seconds to wait for response (default 30)
• optional number bufferSize bytes of memory to allocate for response (min. 4k, max 1M)

Callback Parameters

table response{result, errInfo, received, buffer}

• number result error code of the response (see below)
• string errInfo error description (if result>0)
• number received response length
• string buffer response body

Error Code of the response

• 0 success, response HTTP/GET 2xx
• 22 response HTTP/GET 4xx
• 27 buffer overflow
• 28 response is timed out

Return value

nil

Usage

-- callback function to read the response
local function getResponse{response}
  if response.result > 0 then
    logf("response failed with error code %d.", response.result)
  else
    logf("current credit is %d", tonumber(response.buffer))
  end
end

-- sends HTTP request and handles the response
devices.system.CgiGet{url="http://example.com/getcredit?id=42",getResponse}

Requirements

Netio FirmWare 2.3.5+

See also

• devices.system.CustomCGI() to send HTTP request without response handling