MQTT protocol using resident scripts

[admin]

For testing you can enable "Allow anonymous connections (no username/password)" and remove client:login_set(...) from your script.

Instead of adding log calls to the script you can enable logging for a certain object that will be written to via MQTT. Then you can check the timestamps in Object logs to determine how many telegrams are handled per second.

Code:

require('json')
broker = '127.0.0.1'
port = 1883

mqtt = require('mosquitto')
client = mqtt.new()

client.ON_CONNECT = function(status, rc, msg)
  log('connect', status, rc, msg)

  if status then
    client:subscribe('#')
  else
    client:disconnect()
  end
end

client.ON_MESSAGE = function(mid, topic, payload)
  local decoded = json.pdecode(payload)

  if type(decoded) == 'table' then
    for i, m in ipairs(decoded.commands) do
      grp.write(m.alias, m.value)
    end
  end
end

status, rc, msg = client:connect(broker, port)

client:loop_forever()

Some further improvements can be made with object datatype caching. Otherwise each grp.write call requires a database query to determine the object data type. But keep in mind that the main bottleneck is KNX/TP low speed.