MQTT subscribe

[pentadom]

Hello,

I'm trying to subscribe to a MQTT topic ("arqueta/humedad") and asign his value to an object of logic machine.

I'm using de test Mosquitto broker and I publish previously a value to the topic "arqueta/humedad".

I'm using this code (extracted from here) as a resident script but It seems doesn't works and I don't know what I'm doing wrong...

Code:

-- Define a function which is called by mqtt_client:handler(),
-- whenever messages are received on the subscribed topics

    function callback(topic, message)
    print("Received: " .. topic .. ": " .. message)
    if (message == "quit") then running = false end
  end

-- Create an MQTT client instance, connect to the MQTT server and
-- subscribe to the topic called "arqueta/humedad"

    MQTT = require("mosquitto")
  MQTT.Utility.set_debug(true)
    mqtt_client = MQTT.client.create("https://test.mosquitto.org", 1883, callback)
    mqtt_client:connect("logicmachine")
    local humedad = mqtt_client:subscribe("arqueta/humedad")
    grp.update('1/1/27', humedad)


-- Continously invoke mqtt_client:handler() to process the MQTT protocol and
-- handle any received messages.  Also, publish a message on topic "test/1"

  running = true

  while (running) do
    mqtt_client:handler()
    mqtt_client:publish("test/1", "test message")
    socket.sleep(1.0)  -- seconds
  end

-- Clean-up by unsubscribing from the topic and closing the MQTT connection

  mqtt_client:unsubscribe({"arqueta/humedad"})
  mqtt_client:destroy()

[admin]

Upgrade firmware to 2018 RC1. It has built-in MQTT library support and some other features required for this script.

Create resident script with 0 sleep interval. Change broker IP address and mapping tables as needed.
mqtt_to_object maps topic to a group address, object_to_mqtt maps group address to atopic.

Do full script restart via disable/enable when changing any mapping tables and/or broker address.

Code:

if not broker then
  broker = '192.168.1.101'

  function multiply(mult)
    return function(value)
      local num = tonumber(value)
      if num then
        return num * mult
      else
        return value
      end
    end
  end

  -- topic to object map
  mqtt_to_object = {
    ['in/topic1'] = '32/1/1',
    ['in/topic2'] = '32/1/2',
  }

  -- optional topic value conversion function
  mqtt_to_object_conv = {
    ['in/topic1'] = multiply(100),
    ['in/topic2'] = multiply(0.01),
  }

  -- object to topic map
  object_to_mqtt = {
    ['1/1/1'] = 'out/topic1',
    ['1/1/2'] = 'out/topic2',
  }

  datatypes = {}

  grp.sender = 'mq'
  require('socket')

  for addr, _ in pairs(object_to_mqtt) do
    local obj = grp.find(addr)
    if obj then
      datatypes[ addr ] = obj.datatype
    end
  end

  mclient = require('mosquitto').new()

  mclient.ON_CONNECT = function(res, ...)
    log('mqtt connect status', res, ...)

    if res then
      for topic, _ in pairs(mqtt_to_object) do
        mclient:subscribe(topic)
      end
    else
      mclient:disconnect()
    end
  end

  mclient.ON_MESSAGE = function(mid, topic, payload)
    local addr = mqtt_to_object[ topic ]
    if addr then
      local fn = mqtt_to_object_conv[ topic ]

      if fn then
        payload = fn(payload)
      end

      grp.write(addr, payload)
    end
  end

  mclient.ON_DISCONNECT = function(...)
    log('mqtt disconnect', ...)
    mclientfd = nil
  end

  function mconnect()
    local fd

    mclient:connect(broker)
    fd = mclient:socket()

    -- fd ref is valid
    if fd then
      mclientfd = fd
    end
  end

  mconnect()

  function publishvalue(event)
    -- message from us or client is not connected
    if event.sender == 'mq' or not mclientfd then
      return
    end

    local addr = event.dst
    local dpt = datatypes[ addr ]
    local topic = object_to_mqtt[ addr ]

    -- unknown object
    if not dpt or not topic then
      return
    end

    local value = busdatatype.decode(event.datahex, dpt)
    if value ~= nil then
      if type(value) == 'boolean' then
        value = value and 1 or 0
      end

      mclient:publish(topic, tostring(value))
    end
  end

  lbclient = require('localbus').new(1)
  lbclient:sethandler('groupwrite', publishvalue)

  lbclientfd = socket.fdmaskset(lbclient:getfd(), 'r')

  -- run timer every 5 seconds
  timer = require('timerfd').new(5)
  timerfd = socket.fdmaskset(timer:getfd(), 'r')
end

-- mqtt connected
if mclientfd then
  mclientfdset = socket.fdmaskset(mclientfd, mclient:want_write() and 'rw' or 'r')
  res, lbclientstat, timerstat, mclientstat =
      socket.selectfds(10, lbclientfd, timerfd, mclientfdset)
-- mqtt not connected
else
  res, lbclientstat, timerstat =
    socket.selectfds(10, lbclientfd, timerfd)
end

if mclientfd and mclientstat then
  if socket.fdmaskread(mclientstat) then
    mclient:loop_read()
  end

  if socket.fdmaskwrite(mclientstat) then
    mclient:loop_write()
  end
end

if lbclientstat then
  lbclient:step()
end

if timerstat then
  -- clear armed timer
  timer:read()

  if mclientfd then
    mclient:loop_misc()
  else
    mconnect()
  end
end

[pentadom]

Upgrade firmware to 2018 RC1. It has built-in MQTT library support and some other features required for this script.

Create resident script with 0 sleep interval. Change broker IP address and mapping tables as needed.
mqtt_to_object maps topic to a group address, object_to_mqtt maps group address to atopic.

Do full script restart via disable/enable when changing any mapping tables and/or broker address.

I'm trying to do this but it doesn't works. I supose that when I send a value to the broker, automatically the script must receive the value? 

I've just upgrade the firmware. Here's the actual version:



Here's my code where I put the mosquitto test broker and the topic "arqueta/humedad" I'm testing. the object 32/1/1 is a "05. 1 byte unsigned integer".

As I say, it doesn't works and I don't know what I'm doing wroing.

---

The correct line to broker is without "http://"

broker = 'test.mosquitto.org'

Now it works the suscribe.

[Dario]

Hi!

I have problem with object_to_mqtt this topic will change on MQTT when I write new value? Is it necessary event script? Now I don't see change this value on client.

[admin]

No event script is needed. Value is published to selected topic when value changes. Have you checked that MQTT client is connected? Does the reverse (mqtt_to_object) work? Does the client have access to the select topic?
You can log the publish result like this (line 83):

Code:

local r, e, c = mclient:publish(topic, tostring(value))
log('publish', r, e, c)

[Dario]

Solved! the problem was client software that I used, MQTT_to_object worked but no the reverse.

[Tifon]

Admin thank you for this code!, it works great.

But how can i apply a scale factor to one of the "mqtt_to_object"?

[admin]

I've updated example post. Edit mqtt_to_object_conv table as needed, custom conversion functions can be added as well.

[dharma@srujan-infotech.com]

I've updated example post. Edit mqtt_to_object_conv table as needed, custom conversion functions can be added as well.

Hi,
in my case am using LM as broker and i need to Publish/subscribe single topic Message payloads to different group address?


how to achieve below criteria in LM5

ex: for  relay-1 is 0/0/1 as group address  
topic=100
Payload on=C,1,1,\r\n
Payload off =C,1,0,\r\n

for relay-2 is 0/0/2 as group address 
topic=100
Payload on=C,2,1,\r\n
Payload off=C,2,0,\r\n

[admin]

Add custom logic to the MQTT callbacks:

Code:

mclient.ON_CONNECT = function(res, ...)
  log('mqtt connect status', res, ...)

  if res then
    mclient:subscribe('100')
  else
    mclient:disconnect()
  end
end

mclient.ON_MESSAGE = function(mid, topic, payload)
  if topic == '100' then
    if payload == "C,1,1,\r\n" then
      grp.write('0/0/1', true)
    elseif payload == "C,1,0,\r\n" then
      grp.write('0/0/1', false)
    elseif payload == "C,2,1,\r\n" then
      grp.write('0/0/2', true)
    elseif payload == "C,2,0,\r\n" then
      grp.write('0/0/2', false)
    end
  end
end

Using one topic for controlling multiple entities is bad system design. Each relay should have it's own topic for control if possible.

[dharma@srujan-infotech.com]

Hi,
please elaborate this custom Logic in Mqtt callbacks where we can i find
actually am adding this logic in main residence script please find it in attached file(how we have done)
am doing it in correct way...?

[admin]

Looks correct, add logging for each received message in case it does not work:

Code:

mclient.ON_MESSAGE = function(mid, topic, payload)
  log(topic, payload)
  ...
end

[dharma@srujan-infotech.com]

Looks correct, add logging for each received message in case it does not work:

Code:

mclient.ON_MESSAGE = function(mid, topic, payload)
  log(topic, payload)
  ...
end

Hi,

Please find attached snap shots of Logs

[admin]

Check the latest log entry, it shows what data was published to the topic named "100". Modify the ON_MESSAGE callback function to execute actions based on the received payload:

Code:

mclient.ON_MESSAGE = function(mid, topic, payload)
  log('ON_MESSAGE ', topic, payload)
  if topic == '100' then
    if payload == "11" then
      grp.write('0/0/1', true)
    elseif payload == "10" then
      grp.write('0/0/1', false)
   end
  end
end

You can use MQTT explorer (http://mqtt-explorer.com/) to connect to LM and send any data to any topics to test your scripts.

[myg]

alternatively you can use my declarative binding for mqtt2knx integration, although it was created for zigbee2mqtt topics
https://forum.logicmachine.net/showthread.php?tid=2671

[dharma@srujan-infotech.com]

Hi,
in this case the publishing topic=100, and Payload=C,1,1,1,\r\n like this format while subscribing topic=100 and msg Payload=$FD;2;4;0;0;0;0;0;0;@ while watching from LM log  we found this.

[admin]

Modify the example in my previous post and implement your custom actions based on the received payload value.

[dharma@srujan-infotech.com]

Modify the example in my previous post and implement your custom actions based on the received payload value.

Hi, 
modification according to the log it is working fine... for Boolean objects but when it comes to light Dimming and Fan regulator the commands are different for each value can you please update that conversation according to the following parameters..

group address to Mqttpublish)
fan speed1_very low----->C,5,1,\r\n
fanspped-low         ------>C,5,2,\r\n
fanspeed_medium  ------>C,5,3,\r\n
fanspeed_High        ----->C,5,4,\r\n
fan_off                    ----->C,5,0\r\n

mqtt to group addressSubscribe)
fan speed1_very low----->C,5,1
fanspped-low         ------>C,5,2
fanspeed_medium  ------>C,5,3
fanspeed_High        ----->C,5,4
fan_off                    ----->C,5,0

[admin]

You can use 1-byte object with custom values to control values as is (0=off, 4=highest).
Then to convert object value to payload use this:

Code:

payload = 'C,5,' .. value .. '\r\n'

To convert payload back to the value use this:

Code:

value = payload:match('C,%d,(%d)')

[a455115]

Hello,

I use the thread to ask:
I need to introduce MQTT actuators of damphos in many rooms. How can I scan the broker for devices and automatically create objects with their names? For example, my punishments will have a topic:
Danfos /room_001...
Danfos /room_200....
How to get the names directly from the broker and create the objects I need - I will need several objects with different types of variables?