SHAC/MQTT/HomeAssistant recall previous level

TL: DR> Get HomeAssistant working with CBus with a SHAC and without C-Gate.

I got sick of MisterHouse. OMG, it's sooo ten years ago and no longer developed, and good riddance given the bolts-hanging-out-of-its-neck integration with CBus and Google Assistant.

And then on replacing it, I rapidly got sick of HomeAssistant with Google integration setting my CBus lights to 100% for 'on' every time I barked "Hoy Google, Turn on the dunny light"... I wanted Google/HA to remember the previous 'on' ramp level. MisterHouse used to do it, even if it was a pig (so I s'pose it had some lipstick after all...)

Which it turned out was easier said than done for HA.

Sooo I did... my code below.

Some notes:

• I don't care about security on my MQTT broker. There is no username/password, so adjust to suit.
• Obviously change the broker address
• Obviously change the client names to avoid collissions with existing clients
• 'Last Levels' are stored frequently when changed, so should survive reboots / script restarts on the SHAC
• I had to set a MQTT client keep-alive to 25 seconds. I'm using mosquitto broker on my network, and anything 30 seconds or above it hated for some reason and kicked the connections repeatedly. I had to do the same with HomeAssistant too. It shouldn't be needed, as default should have worked, but it didn't, because the server should listen to what the client wants. So that's the '25' in each client:connect statement. YMMV depending on broker...
• I haven't implemented MQTT discovery. Ugh. Next level. That's for another day.

And lastly, if there is another far easier way to achieve this, like a "FFS Remember My Last Levels" setting anywhere in HA then PLEASE ... shoot me down and point out that setting in HA ASAP... I would gladly throw away a day of wasted coding for that nugget.

I might have forgotten to share some aspect. If I have, hit me up for whatever.

Event-based script, on tag = MQTT for the groups you want integrated:

Code:

--[[
Pushes CBus events to MQTT resident scripts via internal sockets.

Tag required objects with the "MQTT" keyword and this script will run whenever one of those objects change.
--]]

dataparts = string.split(event.dst, "/")
lastLevel = GetCBusLevel(dataparts[1], dataparts[2], dataparts[3])

-- Send an event to MQTT send to publish
require('socket').udp():sendto(event.dst .. "/" .. event.getvalue(), '127.0.0.1', 5432)

-- Send an event to MQTT receive to save lastlevel
require('socket').udp():sendto(event.dst .. "/" .. event.getvalue(), '127.0.0.1', 5433)

Resident 'MQTT send', seleep interval zero, but that doesn't matter as it never exits...

Code:

--[[
Push Cbus events to MQTT
--]]

logging = false

mqtt_broker = '192.168.9.10'
-- mqtt_username = 'YOUR_MQTT_USERNAME'
-- mqtt_password = 'YOUR_MQTT_PASSWORD'
mqtt_clientid = 'shac-send'

mqtt_read_topic = 'cbus/read/'

socket = require('socket')

unpublished = {}
notify = true

function publishCurrent()
  mqttP = GetCBusByKW('MQTT', 'or')
  n = 1
  for k, v in pairs(mqttP) do
    app = tonumber(v['address'][2])
    group = tonumber(v['address'][3])
    unpublished[n] = {app=app, group=group}
    n = n + 1
  end
end

mqtt = require('mosquitto')
client = mqtt.new(mqtt_clientid)
server = require('socket').udp()
server:settimeout(0.5)
server:setsockname('127.0.0.1', 5432)

client.ON_CONNECT = function()
  log('MQTT send connected')
  publishCurrent()
end

client.ON_DISCONNECT = function(...)
  log('MQTT send disconnected')
  notify = true
end

-- client:login_set(mqtt_username, mqtt_password)
client:connect(mqtt_broker, 1883, 25)
client:loop_start()

while true do
  function publish(network, app, group, level)
      state = (level ~= 0) and 'ON' or 'OFF'
    client:publish(mqtt_read_topic .. network .. '/' .. app .. '/' .. group .. '/state', state, 1, true)
    client:publish(mqtt_read_topic .. network .. '/' .. app .. '/' .. group .. '/level', level, 1, true)
    if logging then log('Publishing state and level ' .. mqtt_read_topic .. network .. '/' .. app .. '/' .. group .. ' to ' .. state .. '/' .. level) end
  end
 
    cmd = server:receive()
    if cmd and type(cmd) == 'string' then
    parts = string.split(cmd, '/')
    publish(254, tonumber(parts[2]), tonumber(parts[3]), tonumber(parts[4]))
    end
  if #unpublished > 0 then
        if notify then
      log('Publishing current levels')
      notify = false
    end
    publish(255, unpublished[1].app, unpublished[1].group, GetCBusLevel(0, unpublished[1].app, unpublished[1].group))
    table.remove(unpublished, 1)
    if #unpublished == 0 then log('Publishing current levels completed') end
  end
end

And a resident 'MQTT receive', again sleep doesn't matter...

Code:

--[[
Push MQTT events to Cbus
--]]

logging = false

mqtt_broker = '192.168.9.10'
-- mqtt_username = 'YOUR_MQTT_USERNAME'
-- mqtt_password = 'YOUR_MQTT_PASSWORD'
mqtt_clientid = 'shac-receive'

mqtt_read_topic = 'cbus/read/'
mqtt_write_topic = 'cbus/write/#';

-- load mqtt module and create UDP server
mqtt = require('mosquitto')
server = require('socket').udp()
server:settimeout(0.5)
server:setsockname('127.0.0.1', 5433)


lastLevel = {}

function saveLastLevel()
  local ll = {}
  for k, v in pairs(lastLevel) do
    table.insert(ll, k..'='..v)
  end
  local lls = table.concat(ll, ',')
  old = storage.get('lastLevel', '')
  if lls ~= old then
    log('Saving last levels')
      storage.set('lastLevel', lls)
  end
end

function loadLastLevel()
  local lls = storage.get('lastLevel', '')
  local llt = string.split(lls, ',')
  for _, v in ipairs(llt) do
    parts = string.split(v, '=')
    lastLevel[parts[1]] = parts[2]
  end
end

loadLastLevel()


-- create new mqtt client
client = mqtt.new(mqtt_clientid)

client.ON_CONNECT = function(success)
  if (success) then
    log('MQTT receive connected')
    local mid = client:subscribe(mqtt_write_topic, 2)
  end
end

client.ON_DISCONNECT = function(...)
  log('MQTT receive disconnected')
end

client.ON_MESSAGE = function(mid, topic, payload)
  if logging then log(topic .. ' to ' .. payload) end
 
  parts = string.split(topic, '/')

  if not parts[6] then
    log('MQTT error: Invalid message format')

  elseif parts[6] == 'getall' then
    datatable = grp.all()
    for key,value in pairs(datatable) do
      parts = string.split(value.address, '/')
            network = tonumber(parts[1])
            app = tonumber(parts[2])
      group = tonumber(parts[3])
      if app == tonumber(parts[4]) and group ~= 0 then
                level = tonumber(value.data)
                state = (level ~= 0) and 'ON' or 'OFF'
        if logging then log(parts[3], app, group, state, level) end
        client:publish(mqtt_read_topic .. parts[3] .. '/' .. app .. '/' .. group .. '/state', state, 1, true)
                client:publish(mqtt_read_topic .. parts[3] .. '/' .. app .. '/' .. group .. '/level', level, 1, true)
            end   
        end

  elseif parts[6] == 'switch' then
    if payload == 'ON' then
      if logging then log('Payload is ON') end
            SetCBusLevel(0, parts[4], parts[5], 255, 0)
    elseif payload == 'OFF' then
      if logging then log('Payload is OFF') end
      SetCBusLevel(0, parts[4], parts[5], 0, 0)
    end
    
  elseif parts[6] == 'measurement' then        -- UNTESTED
        SetCBusMeasurement(0, parts[4], parts[5], payload, 0)
    
  elseif parts[6] == 'ramp' then
    if payload == 'ON' then
      if logging then log('Payload is ON') end
            SetCBusLevel(0, parts[4], parts[5], 255, 0)
    elseif payload == 'OFF' then
      if logging then log('Payload is OFF') end
      SetCBusLevel(0, parts[4], parts[5], 0, 0)
    else
      ramp = string.split(payload, ',')
      num = math.floor(ramp[1] + 0.5)
      if num and num < 256 then
        key = '0'..'/'..parts[4]..'/'..parts[5]
        if lastLevel[key] then toSet = lastLevel[key] else toSet = num end
        if ramp[2] ~= nil and tonumber(ramp[2]) > 1 then
                    SetCBusLevel(0, parts[4], parts[5], toSet, ramp[2])
        else
                    SetCBusLevel(0, parts[4], parts[5], toSet, 0)
        end
      end
    end
  end
end

-- client:login_set(mqtt_username, mqtt_password)
client:connect(mqtt_broker, 1883, 25)
client:loop_start()

receivedOff = {}
rampDetect = {}
lastSaved = os.time()

-- Loop looking for lastlevel values
while true do
  cmd = server:receive()
    if cmd and type(cmd) == 'string' then
    if logging then log('Command received: '..cmd) end
    parts = string.split(cmd, '/')
    key = parts[1]..'/'..parts[2]..'/'..parts[3]
    level = tonumber(parts[4])
    if level == 0 then
      if (receivedOff[key] and os.time() - receivedOff[key] >= 30) or not receivedOff[key] then
        receivedOff[key] = os.time()
        rampDetect[key] = nil
        if logging then log('Executing OFF ' .. key) end
        if logging then log('Last received OFF '..receivedOff[key]) end
      end
    else
      if logging then log('Executing ON ' .. key) end
      ll = 0
      if not rampDetect[key] then
        rampDetect[key] = level
      end
      if receivedOff[key] and os.time() - receivedOff[key] < 30 then
        if logging then log('Last received OFF '..receivedOff[key]) end
        if level > rampDetect[key] then -- must be ramping on
          ll = level
        end
      end
      if not receivedOff[key] or os.time() - receivedOff[key] > 30 then
        ll = level
      end
      if ll > 0 then
        if logging then log('Saving lastlevel of '..level) end
        lastLevel[key] = ll
            end
    end
    end
  if os.time() - lastSaved > 60 then
    saveLastLevel()
    lastSaved = os.time()
  end
end

And in HomeAssistant configuration.yaml...

Code:

mqtt:
   client_id: hass     
   keepalive: 20   
                  
light: !include map59-light.yaml
switch: !include map59-switch.yaml

And an example in map59-light.yaml...

Code:

  - platform: mqtt
    state_topic: "cbus/read/254/56/7/state"
    command_topic: "cbus/write/254/56/7/switch"
    brightness_state_topic: "cbus/read/254/56/7/level"
    brightness_command_topic: "cbus/write/254/56/7/ramp"
    payload_off: "OFF"
    on_command_type: "brightness"
    name: Main
    unique_id: mq_dining_room

And map59-switch.yaml...

Code:

  - platform: mqtt
    state_topic: "cbus/read/254/56/111/state"
    command_topic: "cbus/write/254/56/111/switch"
    payload_off: "OFF"
    payload_on: "ON"
    name: Pool Side Heater 1
    unique_id: mq_hutch_heater_1

 

Bug in 'MQTT receive'... sorry...

Line that reads:

Code:

        if lastLevel[key] then toSet = lastLevel[key] else toSet = num end

Should be:

Code:

        if lastLevel[key] and payload == 255 then toSet = lastLevel[key] else toSet = num end

And another one in 'MQTT send'... again sorry...

Line that reads:

Code:

    publish(255, unpublished[1].app, unpublished[1].group, GetCBusLevel(0, unpublished[1].app, unpublished[1].group))

Should be:

Code:

    publish(254, unpublished[1].app, unpublished[1].group, GetCBusLevel(0, unpublished[1].app, unpublished[1].group))[CODE]

 

Stupid 120 minute edit limit...

Code:

        if lastLevel[key] and num == 255 then toSet = lastLevel[key] else toSet = num end

Plus, I have number/string confusion. I love/hate LUA... In 'MQTT receive':

Code:

    lastLevel[parts[1]] = tonumber(parts[2])

And for some LUA reason:

Code:

        lastLevel[key] = tonumber(ll)

I'll get back to you with MQTT discovery code. It's not simple in my case, but my example should turn on light bulbs, pardon the pun for some in terms of setting icons/preferred areas and manipulating desired names for HomeAssistant.

 

MQTT / HomeAssistant discovery is implemented. That bit is a bit of a dog's breakfast, but simple enough to follow.

So it turns out that trying to use a UDP socket to receive "last levels" in conjunction with the same mosquitto receive resident script ends in badness. This is what I had previously. A kind of lock-up-the-script-and-stop-working badness... and at one stage, power off/on the SHAC badness. Weird stuff that staring at the code to find an issue could not resolve. So I split out the "last level" business into its own resident and used SHAC storage.

The issues doing this with the code earlier seemed to occur randomly, but occurred always when asking HomeAssistant to do many things together, like turn on a whole room. Some things would turn on, and then scripts would hang.

It seems to work like a champ now, plus with no manual configuration of entities in HomeAssistant because discovery. HA needs to be configured to listen to the topic 'cbus'. I tossed this in my configuration.yaml:

Code:

mqtt:
  client_id: hass
  keepalive: 20
  discovery_prefix: cbus

Cheers.

Event-based on keyword "MQTT", or whatever you choose:

Code:

--[[
Pushes CBus events to MQTT resident scripts via internal sockets.

Tag required objects with the "MQTT" keyword and this script will run whenever one of those objects change
--]]

-- Send an event to MQTT send to publish
require('socket').udp():sendto(event.dst .. "/" .. event.getvalue(), '127.0.0.1', 5432)

-- Send an event to MQTT receive to save lastlevel
require('socket').udp():sendto(event.dst .. "/" .. event.getvalue(), '127.0.0.1', 5433)

Resident MQTT send/zero sleep because infinte loop so it doesn't Parramatta. Note the dog's breakfast name/suggested area/image manipulation:

Code:

--[[
Push Cbus events to MQTT
--]]

logging = false

mqtt_broker = '192.168.9.10'
-- mqtt_username = 'YOUR_MQTT_USERNAME'
-- mqtt_password = 'YOUR_MQTT_PASSWORD'
mqtt_clientid = 'shac-send'

mqtt_read_topic = 'cbus/read/'
mqtt_discovery_topic = 'cbus'

socket = require('socket')

unpublished = {}
notify = true
status = 0

function publishCurrent()
  mqttP = GetCBusByKW('MQTT', 'or')
  n = 1
  for k, v in pairs(mqttP) do
    app = tonumber(v['address'][2])
    group = tonumber(v['address'][3])
    unpublished[n] = {app=app, group=group}
    n = n + 1
  end
end

mqtt = require('mosquitto')
client = mqtt.new(mqtt_clientid)
server = require('socket').udp()
server:settimeout(0.25)
server:setsockname('127.0.0.1', 5432)

client.ON_CONNECT = function(success)
  if success then
      log('MQTT send connected')
    status = 1
      publishCurrent()
  end
end

client.ON_DISCONNECT = function(...)
  log('MQTT send disconnected')
  notify = true
  status = 2
end

-- client:login_set(mqtt_username, mqtt_password)
client:connect(mqtt_broker, 1883, 25)
client:loop_start()

function publish(net, app, group, level)
  state = (level ~= 0) and 'ON' or 'OFF'
  client:publish(mqtt_read_topic..net..'/'..app..'/'..group..'/state', state, 1, true)
  client:publish(mqtt_read_topic..net..'/'..app..'/'..group..'/level', level, 1, true)
  if logging then log('Publishing state and level '..mqtt_read_topic..net..'/'..app..'/'..group..' to '..state..'/'..level) end
end

function unpublish(net, app, group)
  client:publish(mqtt_read_topic..net..'/'..app..'/'..group..'/state', '', 1, true)
  client:publish(mqtt_read_topic..net..'/'..app..'/'..group..'/level', '', 1, true)
end

function begins(prefix, text)
  pos = text:find(prefix, 1, true)
  if pos then return pos == 1 else return false end
end

function contains(prefix, text)
  pos = text:find(prefix, 1, true)
  if pos then return pos >= 1 else return false end
end

function addDiscover(net, app, group)
  local name = GetCBusGroupTag(0, app, group)
  local sa = ''
  local img = ''
  local dType = ''
  local preferName = ''

  -- Set suggested area
    if     begins('Kitchen', name) then sa = 'Kitchen'
  elseif begins('Family', name) then sa = 'Family Room'
  elseif begins('Formal', name) then sa = 'Front Lounge'
  elseif begins('Dining', name) then sa = 'Dining Room'
  elseif begins('Bedroom 1', name) then sa = 'Bedroom 1'
  elseif begins('Bedroom 2', name) then sa = 'Bedroom 2'
  elseif begins('Bedroom 3', name) then sa = 'Bedroom 3'
  elseif begins('Bathroom 1', name) then sa = 'Bathroom 1'
  elseif begins('Bathroom 2', name) then sa = 'Bathroom 2'
  elseif begins('Hall', name) then sa = 'Hall'
  elseif begins('Den', name) then sa = 'Den'
  elseif begins('Laundry', name) then sa = 'Den'
  elseif begins('Outside', name) then sa = 'Outside'
    elseif begins('Hutch Bathroom', name) then sa = 'Hutch Bathroom'
  elseif begins('Hutch Kitchen', name) then sa = 'Hutch Kitchen'
  elseif begins('Hutch', name) then sa = 'Hutch'
  elseif begins('Open', name) then sa = 'Outside'
  elseif begins('Close', name) then sa = 'Outside'
  elseif begins('Pool', name) then sa = 'Pool'
  elseif begins('Spa', name) then sa = 'Pool'
  else sa = 'Unknown'
  end
  log(name..' in '..sa)

  -- Set image
    if     contains('Pool Heat', name) then img = 'mdi:pump'
    elseif contains('Heat', name) then img = 'mdi:radiator'
    elseif contains('Pump', name) then img = 'mdi:pump'
    elseif contains('Blower', name) then img = 'mdi:chart-bubble'
    elseif contains('Gate', name) and contains('Open', name) then img = 'mdi:gate-open'
    elseif contains('Gate', name) and contains('Close', name) then img = 'mdi:gate'
    elseif contains('Sensors', name) then img = 'mdi:motion-sensor-off'
    elseif contains('Fan', name) then img = 'mdi:fan'
    elseif contains('Rail Enable', name) then img = 'mdi:radiator-disabled'
    elseif contains('Towel Rail', name) then img = 'mdi:radiator'
    elseif contains('Floor Enable', name) then img = 'mdi:radiator-disabled'
    elseif contains('Under Floor', name) then img = 'mdi:radiator'
  else img = 'mdi:lightbulb'
  end

    -- Adjust the device name
    if     contains('Pantry LV', name) then preferName = 'Pantry'
    elseif contains('Dining LV', name) then preferName = 'Perimeter'
    elseif contains('Formal LV', name) then preferName = 'Perimeter'
    --elseif contains('Perimeter', name) then preferName = 'Perimeter'
    elseif contains('Hall Front', name) then preferName = 'Front Hall'
    elseif contains('Hall Mid', name) then preferName = 'Hall'
    elseif contains('Kitchen', name) and contains('LV', name) then preferName = 'Main'
    elseif contains('Bathroom 2', name) and contains('LV 1', name) then preferName = 'Main'
    elseif contains('Bathroom 2', name) and contains('LV 2', name) then preferName = 'Spa'
    elseif contains('Laundry', name) and not contains('Outside', name) then preferName = 'Laundry'
    elseif contains('Bedroom 1 LV', name) then preferName = 'Wardrobe'
    elseif contains('Dining Garden', name) then preferName = 'Outside Cat Hutch'
    elseif contains('Verandah Pendant', name) then preferName = 'Verandah'
    elseif contains('Verandah LV', name) then preferName = 'Verandah Perimeter'
    elseif contains('Hutch Bathroom', name) then preferName = 'Main'
    elseif contains('Hutch Kitchen', name) then preferName = 'Galley'
    elseif contains('Heat 1', name) then preferName = 'Pool Side Heater 1'
    elseif contains('Heat 2', name) then preferName = 'Pool Side Heater 2'
    elseif contains('Heat 3', name) then preferName = 'TV Side Heater 1'
    elseif contains('Heat 4', name) then preferName = 'TV Side Heater 2'
    elseif contains('Pendant', name) then preferName = 'Main'
    elseif contains('LV', name) then preferName = 'Main'
  else preferName = name
  end

  -- Set type of device
  if img == 'mdi:lightbulb' then
    dType = 'light'
  else
    dType = 'switch'
  end

  oid = 'cbus_mqtt_'..net..'_'.. app..'_'.. group

  if dType == 'light' then
    payload = {
      ['name'] = preferName,
      ['unique_id'] = oid,
      ['ic'] = img,
      ['dev'] = {
        ['ids'] = oid,
        ['sa'] = sa
      },
      ['stat_t'] = 'cbus/read/'..net..'/'..app..'/'..group..'/state',
      ['cmd_t'] = 'cbus/write/'..net..'/'..app..'/'..group..'/switch',
      ['bri_stat_t'] = 'cbus/read/'..net..'/'..app..'/'..group..'/level',
      ['bri_cmd_t'] = 'cbus/write/'..net..'/'..app..'/'..group..'/ramp',
      ['pl_off'] = 'OFF',
      ['on_cmd_type'] = 'brightness',
    }
  elseif dType == 'switch' then
    payload = {
      ['name'] = preferName,
      ['unique_id'] = oid,
      ['ic'] = img,
      ['dev'] = {
        ['ids'] = oid,
        ['sa'] = sa
      },
      ['stat_t'] = 'cbus/read/'..net..'/'..app..'/'..group..'/state',
      ['cmd_t'] = 'cbus/write/'..net..'/'..app..'/'..group..'/switch',
      ['pl_on'] = 'ON',
      ['pl_off'] = 'OFF',
    }
  end

  local j = json.encode(payload)
  local topic = mqtt_discovery_topic..'/'..dType..'/'..oid..'/config'
--  log(topic)
--  log(j)

    client:publish(mqtt_discovery_topic..'/'..'light'..'/'..'cbus_mqtt_254_56_33'..'/config', '', 1, true)
  if sa == 'deleteme' then
    client:publish(topic, '', 1, true)
  else
      client:publish(topic, j, 1, true)
  end
end

while true do
    cmd = server:receive()
    if cmd and type(cmd) == 'string' then
    parts = string.split(cmd, '/')
    publish(254, tonumber(parts[2]), tonumber(parts[3]), tonumber(parts[4]))
    end

  if #unpublished > 0 then
        if notify then
      log('Publishing current levels')
      notify = false
    end
    addDiscover(254, unpublished[1].app, unpublished[1].group)
    -- unpublish(255, unpublished[1].app, unpublished[1].group) -- clean up from a bug
    publish(254, unpublished[1].app, unpublished[1].group, GetCBusLevel(0, unpublished[1].app, unpublished[1].group))
    table.remove(unpublished, 1)
    if #unpublished == 0 then log('Publishing current levels completed') end
  end

  if status == 2 then
    log('MQTT send reconnection')
    if client:reconnect() then
      status = 1
    end
  end
end

And then the MQTT receive resident/zero. There's a "getall" that still wants work. The major change here from earlier is to switch to a loop_forever() in favour of loop_start(), from which I subsequently looked for socket receive in an infinite loop, which worked usually, but broke when loaded up with many things to do.

Code:

--[[
Push MQTT events to Cbus
--]]

logging = false

mqtt_broker = '192.168.9.10'
-- mqtt_username = 'YOUR_MQTT_USERNAME'
-- mqtt_password = 'YOUR_MQTT_PASSWORD'
mqtt_clientid = 'shac-receive'

mqtt_read_topic = 'cbus/read/'
mqtt_write_topic = 'cbus/write/#';

-- load mqtt module and create UDP server
mqtt = require('mosquitto')

status = 0

lastLevel = {}
lls = ''

function loadLastLevel()
  local llsTest = storage.get('lastLevel', '')
  if llsTest ~= lls then
    lls = llsTest
    local llt = string.split(lls, ',')
    for _, v in ipairs(llt) do
      parts = string.split(v, '=')
      lastLevel[parts[1]] = tonumber(parts[2])
    end
    end
end


-- create new mqtt client
client = mqtt.new(mqtt_clientid)

client.ON_CONNECT = function(success)
  if (success) then
    log('MQTT receive connected')
    status = 1
    local mid = client:subscribe(mqtt_write_topic, 2)
  end
end

client.ON_DISCONNECT = function(...)
  log('MQTT receive disconnected')
  status = 2
end

client.ON_MESSAGE = function(mid, topic, payload)
  if logging then log(topic .. ' to ' .. payload) end

  loadLastLevel()

  local parts = string.split(topic, '/')
  local net = 0
  local app = tonumber(parts[4])
  local group = tonumber(parts[5])

  if not parts[6] then
    log('MQTT error: Invalid message format')

  --[[
  NEEDS TO BE MODIFIED to just publish our groups of interest!!! Currently doing all groups
    GetCBusByKW('MQTT', 'or')

  elseif parts[6] == 'getall' then
    local datatable = grp.all()
    for key,value in pairs(datatable) do
      parts = string.split(value.address, '/')
            net = tonumber(parts[1])
            app = tonumber(parts[2])
      group = tonumber(parts[3])
      if app == tonumber(parts[4]) and group ~= 0 then
                level = tonumber(value.data)
                state = (level ~= 0) and 'ON' or 'OFF'
        if logging then log(parts[3], app, group, state, level) end
        client:publish(mqtt_read_topic .. net .. '/' .. app .. '/' .. group .. '/state', state, 1, true)
                client:publish(mqtt_read_topic .. net .. '/' .. app .. '/' .. group .. '/level', level, 1, true)
            end 
        end
  --]]

  elseif parts[6] == 'switch' then
    if payload == 'ON' then
      if logging then log('Payload is ON') end
            SetCBusLevel(0, app, group, 255, 0)
    elseif payload == 'OFF' then
      if logging then log('Payload is OFF') end
      SetCBusLevel(0, app, group, 0, 0)
    end
  
  elseif parts[6] == 'measurement' then        -- UNTESTED
        SetCBusMeasurement(0, app, group, payload, 0)
  
  elseif parts[6] == 'ramp' then
    if payload == 'ON' then
      if logging then log('Payload is ON') end
            SetCBusLevel(0, app, group, 255, 0)
    elseif payload == 'OFF' then
      if logging then log('Payload is OFF') end
      SetCBusLevel(0, app, group, 0, 0)
    else
      local key = '0'..'/'..app..'/'..group
      parts = string.split(payload, ',')
      local lev = tonumber(parts[1])
      local num = math.floor(lev + 0.5)
      if num and num < 256 then
          if logging then log('Payload is RAMP '..payload) end
        local toSet = 0
        local ramp = 0
        if logging and lastLevel[key] then log('Last level '..lastLevel[key]) end
        if lastLevel[key] and num == 255 then toSet = lastLevel[key] else toSet = num end
        if parts[2] ~= nil then ramp = tonumber(parts[2]) else ramp = 0 end
                SetCBusLevel(0, app, group, toSet, ramp)
      end
    end
  end
end

-- client:login_set(mqtt_username, mqtt_password)
client:connect(mqtt_broker, 1883, 25)
client:loop_forever()

And finally the MQTT lastlevel resident/zero sleep script, which receives messages from groups of interest and manages the lastLevel storage. Saves every two seconds should there be any change.

Code:

logging = false

server = require('socket').udp()
server:settimeout(0.5)
server:setsockname('127.0.0.1', 5433)

lastLevel = {}
receivedOff = {}
rampDetect = {}
lastSaved = os.time()

function loadLastLevel()
    lls = storage.get('lastLevel', '')
  llt = string.split(lls, ',')
  for _, v in ipairs(llt) do
    parts = string.split(v, '=')
    lastLevel[parts[1]] = tonumber(parts[2])
  end
end

function saveLastLevel()
  local ll = {}
  for k, v in pairs(lastLevel) do
    table.insert(ll, k..'='..v)
  end
  local lls = table.concat(ll, ',')
  old = storage.get('lastLevel', '')
  if lls ~= old then
      storage.set('lastLevel', lls)
    log('Saved last levels')
  end
end

function processCommand(cmd)
    if logging then log('Command received: '..cmd) end
  local parts = string.split(cmd, '/')
  local key = parts[1]..'/'..parts[2]..'/'..parts[3]
  local level = tonumber(parts[4])
  if level == 0 then
    if not receivedOff[key] or (receivedOff[key] and os.time() - receivedOff[key] >= 30) then
      receivedOff[key] = os.time()
      rampDetect[key] = nil
      if logging then log('Executing OFF ' .. key) end
      if logging then
        if receivedOff[key] then log('Last received OFF '..receivedOff[key]..' more than 30 seconds ago') else log('Last received OFF never') end
      end
    end
  else
    if logging then log('Executing ON ' .. key) end
    local ll = 0
    if not rampDetect[key] then
      rampDetect[key] = level
    end
    if receivedOff[key] and (os.time() - receivedOff[key] < 30) then
      if logging then log('Last received OFF '..receivedOff[key]..' within 30 seconds') end
      if level > rampDetect[key] then -- must be ramping on
        ll = level
      end
    end
    if not receivedOff[key] or (os.time() - receivedOff[key] > 30) then
      if logging then log('Last received off key does not exist or off key is older than 30 seconds') end
      ll = level
    end
    if ll > 0 then
      if logging then log('Saving lastlevel of '..level) end
      lastLevel[key] = ll
    end
  end
end

loadLastLevel()

-- Loop looking for lastlevel values
while true do
  cmd = server:receive()
    if cmd and type(cmd) == 'string' then
    processCommand(cmd)
    end

  if os.time() - lastSaved > 2 then
    saveLastLevel()
    lastSaved = os.time()
  end
end

 

For posterity, in case someone needs/wants similar functionality, the following code has been further tested/debugged/extended.

Discovery and send/receive now incorporates 'covers' and 'fans' as well, as I have some Somfy blinds and a sweep fan controller. The MQTT send script was also sometimes unreliable on re-connect, so keep-alive messaging is implemented to automatically enable/disable that script should it become unresponsive.

To get everything I wanted with CBus/Mosquitto/Home Assistant working well with the SHAC has been quite a learning curve, so it's possible that other strange behaviour will rear its head in future that my code doesn't cover, so your (and my) mileage may vary.

I've been replying to myself in this thread exclusively, so please forgive that. But I don't mind. I'm not a stranger to chatting with myself.

My sincere thanks to others out there that helped me get to this point.

Event-based on keyword "MQTT":

Code:

--[[
Pushes CBus events to MQTT resident scripts via internal sockets.

Tag required objects with the "MQTT" keyword and this script will run whenever one of those objects change
--]]

-- Send an event to publish to broker
require('socket').udp():sendto(event.dst .. "/" .. event.getvalue(), '127.0.0.1', 5432)

-- Send an event to save lastlevel
require('socket').udp():sendto(event.dst .. "/" .. event.getvalue(), '127.0.0.1', 5433)

Resident 'MQTT send' (zero sleep, the name of the script is significant for keep-alive):

Code:

--[[
Push Cbus events to MQTT
--]]

logging = false

mqtt_broker = '192.168.9.10'
-- mqtt_username = 'YOUR_MQTT_USERNAME'
-- mqtt_password = 'YOUR_MQTT_PASSWORD'
mqtt_clientid = 'shac-send'

mqtt_read_topic = 'cbus/read/'
mqtt_discovery_topic = 'cbus'

socket = require('socket')

unpublished = {}
toPublish = 0
published = 0
notify = true
status = 0

function publishCurrent()
  local mqttP = GetCBusByKW('MQTT', 'or')
  n = 1
  for k, v in pairs(mqttP) do
    app = tonumber(v['address'][2])
    group = tonumber(v['address'][3])
    unpublished[n] = {app=app, group=group}
    n = n + 1
  end
  toPublish = n - 1
    published = 0
  log('Queued '..toPublish..' objects with keyword MQTT for publication')
end

function begins(prefix, text)
  pos = text:find(prefix, 1, true)
  if pos then return pos == 1 else return false end
end

function contains(prefix, text)
  pos = text:find(prefix, 1, true)
  if pos then return pos >= 1 else return false end
end

mqtt = require('mosquitto')
client = mqtt.new(mqtt_clientid)
server = require('socket').udp()
server:settimeout(0.5)
server:setsockname('127.0.0.1', 5432)

client.ON_CONNECT = function(success)
  if success then
      log('MQTT send connected')
    status = 1
      publishCurrent()
  end
end

client.ON_DISCONNECT = function(...)
  log('MQTT send disconnected')
  notify = true
  status = 2
end

-- client:login_set(mqtt_username, mqtt_password)
client:connect(mqtt_broker, 1883, 25)
client:loop_start()

function publish(net, app, group, level)
  if contains('Blind', GetCBusGroupTag(0, app, group)) then
      -- state = (level ~= 0) and 'open' or 'closed'
    state = 'stopped'
  else
      state = (level ~= 0) and 'ON' or 'OFF'
  end
  client:publish(mqtt_read_topic..net..'/'..app..'/'..group..'/state', state, 1, true)
  client:publish(mqtt_read_topic..net..'/'..app..'/'..group..'/level', level, 1, true)
  if logging then log('Publishing state and level '..mqtt_read_topic..net..'/'..app..'/'..group..' to '..state..'/'..level) end
end

function unpublish(net, app, group)
  client:publish(mqtt_read_topic..net..'/'..app..'/'..group..'/state', '', 1, true)
  client:publish(mqtt_read_topic..net..'/'..app..'/'..group..'/level', '', 1, true)
  if logging then log('Un-publishing state and level '..mqtt_read_topic..net..'/'..app..'/'..group) end
end

function addDiscover(net, app, group)
  local name = GetCBusGroupTag(0, app, group)
  local sa = ''
  local img = ''
  local dType = ''
  local preferName = ''

  -- Set suggested area
    if     begins('Kitchen', name) then sa = 'Kitchen'
  elseif begins('Family', name) then sa = 'Family Room'
  elseif begins('Formal', name) then sa = 'Front Lounge'
  elseif begins('Dining', name) then sa = 'Dining Room'
  elseif begins('Bedroom 1', name) then sa = 'Bedroom 1'
  elseif begins('Bedroom 2', name) then sa = 'Bedroom 2'
  elseif begins('Bedroom 3', name) then sa = 'Bedroom 3'
  elseif begins('Bathroom 1', name) then sa = 'Bathroom 1'
  elseif begins('Bathroom 2', name) then sa = 'Bathroom 2'
  elseif begins('Hall', name) then sa = 'Hall'
  elseif begins('Den', name) then sa = 'Den'
  elseif begins('Laundry', name) then sa = 'Den'
  elseif begins('Outside', name) then sa = 'Outside'
  elseif contains('Storage', name) then sa = 'Store'
    elseif begins('Hutch Bathroom', name) then sa = 'Hutch Bathroom'
  elseif begins('Hutch Kitchen', name) then sa = 'Hutch Kitchen'
  elseif begins('Hutch', name) then sa = 'Hutch'
  elseif begins('Open', name) then sa = 'Outside'
  elseif begins('Close', name) then sa = 'Outside'
  elseif begins('Pool', name) then sa = 'Pool'
  elseif begins('Spa', name) then sa = 'Pool'
  else sa = 'Unknown'
  end

  -- Set image
    if     contains('Pool Heat', name) then img = 'mdi:pump'
    elseif contains('Heat', name) then img = 'mdi:radiator'
    elseif contains('Pump', name) then img = 'mdi:pump'
    elseif contains('Blower', name) then img = 'mdi:chart-bubble'
    elseif contains('Gate', name) and contains('Open', name) then img = 'mdi:gate-open'
    elseif contains('Gate', name) and contains('Close', name) then img = 'mdi:gate'
    elseif contains('Sensors', name) then img = 'mdi:motion-sensor-off'
  elseif contains('Sweep Fan', name) then img =  'mdi:ceiling-fan'
    elseif contains('Fan', name) then img = 'mdi:fan'
    elseif contains('Rail Enable', name) then img = 'mdi:radiator-disabled'
    elseif contains('Towel Rail', name) then img = 'mdi:radiator'
    elseif contains('Floor Enable', name) then img = 'mdi:radiator-disabled'
    elseif contains('Under Floor', name) then img = 'mdi:radiator'
    elseif contains('Blind', name) then img = 'mdi:blinds'
  else img = 'mdi:lightbulb'
  end

  -- Set type of device
  if img == 'mdi:lightbulb' then dType = 'light'
  elseif img == 'mdi:ceiling-fan' then dType = 'fan'
  elseif img == 'mdi:blinds' then dType = 'cover'
  else dType = 'switch' end

    -- Adjust the device name
    if     contains('Pantry LV', name) then preferName = sa..' Pantry Light'
    elseif contains('Dining LV', name) then preferName = sa..' Perimeter Lights'
    elseif contains('Formal LV', name) then preferName = sa..' Perimeter Lights'
    elseif contains('Bedroom 2', name) then preferName = sa..' Light'
    elseif contains('Bedroom 3', name) then preferName = sa..' Light'
    elseif contains('Hall Front', name) then preferName = 'Front Hall'
    elseif contains('Hall Mid', name) then preferName = 'Hall'
    elseif contains('Floor Enable',name) then preferName = sa..' Under Floor Heating Enable'
    elseif contains('Under Floor', name) then preferName = sa..' Under Floor Heating'
    elseif contains('Kitchen', name) and contains('LV', name) then preferName = sa..' Main Lights'
    elseif contains('Bathroom 2', name) and contains('LV 1', name) then preferName = sa..' Main Lights'
    elseif contains('Bathroom 2', name) and contains('LV 2', name) then preferName = sa..' Spa Lights'
    elseif contains('Laundry', name) and not contains('Outside', name) then preferName = 'Laundry Lights'
    elseif contains('Bedroom 1 LV', name) then preferName = sa..' Wardrobe Lights'
    elseif contains('Dining Garden', name) then preferName = 'Outside Cat Hutch Light'
    elseif contains('Verandah Pendant', name) then preferName = 'Verandah Light'
    elseif contains('Verandah LV', name) then preferName = 'Verandah Perimeter Lights'
    elseif contains('Hutch Bathroom', name) then preferName = sa..' Main Light'
    elseif contains('Hutch Kitchen', name) then preferName = 'Galley Lights'
    elseif contains('Central', name) then preferName = sa..' Central Light'
    elseif contains('Hutch Perimeter', name) then preferName = sa..' Perimeter Lights'
    elseif contains('Hutch Shrubbery', name) then preferName = sa..' Shrubbery Lights'
    elseif contains('Hutch Storage', name) then preferName = 'Store Light'
    elseif contains('BBQ', name) then preferName = sa..' BBQ Light'
    elseif contains('Store Flood', name) then preferName = sa..' Store Flood Light'
    elseif contains('Side Door', name) then preferName = sa..' Side Door Light'
    elseif contains('Laundry Door', name) then preferName = sa..' Laundry Door Light'
  elseif contains('Heat 1', name) then preferName = 'Pool Side Heater 1'
    elseif contains('Heat 2', name) then preferName = 'Pool Side Heater 2'
    elseif contains('Heat 3', name) then preferName = 'TV Side Heater 1'
    elseif contains('Heat 4', name) then preferName = 'TV Side Heater 2'
    elseif contains('Pendant', name) then preferName = sa..' Main Light'
    elseif contains('LV', name) then preferName = sa..' Main Lights'
  elseif dType == 'light' then preferName = name..' Lights'
  else preferName = name
  end

  if logging then log('Publish discovery '..name..' as '..dType..':'..preferName..' in area '..sa) end

  oid = 'cbus_mqtt_'..net..'_'.. app..'_'.. group

  if dType == 'light' then
    payload = {
      ['name'] = preferName,
      ['unique_id'] = oid,
      ['ic'] = img,
      ['dev'] = {
        ['ids'] = oid,
        ['sa'] = sa
      },
      ['stat_t'] = 'cbus/read/'..net..'/'..app..'/'..group..'/state',
      ['cmd_t'] = 'cbus/write/'..net..'/'..app..'/'..group..'/switch',
      ['bri_stat_t'] = 'cbus/read/'..net..'/'..app..'/'..group..'/level',
      ['bri_cmd_t'] = 'cbus/write/'..net..'/'..app..'/'..group..'/ramp',
      ['pl_off'] = 'OFF',
      ['on_cmd_type'] = 'brightness',
    }
  elseif dType == 'switch' then
    payload = {
      ['name'] = preferName,
      ['unique_id'] = oid,
      ['ic'] = img,
      ['dev'] = {
        ['ids'] = oid,
        ['sa'] = sa
      },
      ['stat_t'] = 'cbus/read/'..net..'/'..app..'/'..group..'/state',
      ['cmd_t'] = 'cbus/write/'..net..'/'..app..'/'..group..'/switch',
      ['pl_on'] = 'ON',
      ['pl_off'] = 'OFF',
    }
  elseif dType == 'fan' then
    payload = {
      ['name'] = preferName,
      ['unique_id'] = oid,
      ['ic'] = img,
      ['dev'] = {
        ['ids'] = oid,
        ['sa'] = sa
      },
      ['stat_t'] = 'cbus/read/'..net..'/'..app..'/'..group..'/state',
      ['cmd_t'] = 'cbus/write/'..net..'/'..app..'/'..group..'/ramp',
      ['pl_on'] = 'ON',
      ['pl_off'] = 'OFF',
      ['pr_mode_cmd_t'] = 'cbus/write/'..net..'/'..app..'/'..group..'/ramp',
      ['pr_mode_cmd_tpl'] = '{% if value == "low" %} 86 {% elif value == "medium" %} 170 {% elif value == "high" %} 255 {% endif %}',
      ['pr_mode_stat_t'] = 'cbus/read/'..net..'/'..app..'/'..group..'/level',
      ['pr_mode_val_tpl'] = '{% if value == 0 %} OFF {% elif value == 86 %} low {% elif value == 170 %} medium {% elif value == 255 %} high {% endif %}',
      ['pr_modes'] = {'low', 'medium', 'high'}
        }
  elseif dType == 'cover' then
    payload = {
      ['name'] = preferName,
      ['unique_id'] = oid,
      ['ic'] = img,
      ['dev'] = {
        ['ids'] = oid,
        ['sa'] = sa
      },
      ['stat_t'] = 'cbus/read/'..net..'/'..app..'/'..group..'/state',
      ['cmd_t'] = 'cbus/write/'..net..'/'..app..'/'..group..'/ramp',
      ['pos_open'] = 255,
      ['pos_clsd'] = 0,
        ['pl_open'] = 'OPEN',
        ['pl_cls'] = 'CLOSE',
      ['pos_t'] = 'cbus/read/'..net..'/'..app..'/'..group..'/level',
      ['set_pos_t'] = 'cbus/write/'..net..'/'..app..'/'..group..'/ramp',
        }
  end

  local j = json.encode(payload)
  local topic = mqtt_discovery_topic..'/'..dType..'/'..oid..'/config'

  if sa == 'changeme' then -- Alter 'changeme' to an area name to remove all topics in that area instead of publishing - for debug
    client:publish(topic, '', 1, true)
  else
      client:publish(topic, j, 1, true)
  end
end

heartbeat = os.time()

while true do
    cmd = server:receive()
    if cmd and type(cmd) == 'string' then
    parts = string.split(cmd, '/')
    publish(254, tonumber(parts[2]), tonumber(parts[3]), tonumber(parts[4]))
    end

  if #unpublished > 0 then
        if notify then
      log('Publishing discovery and current level topics')
      notify = false
    end
    addDiscover(254, unpublished[1].app, unpublished[1].group)
    -- unpublish(255, unpublished[1].app, unpublished[1].group) -- clean up from a bug
    publish(254, unpublished[1].app, unpublished[1].group, GetCBusLevel(0, unpublished[1].app, unpublished[1].group))
    table.remove(unpublished, 1)
    published = published + 1
    if #unpublished == 0 then log('Publishing completed of '..published..' discovery and current level topics') end
  end

  if status == 2 then
    log('MQTT send reconnection')
    if client:reconnect() then
      status = 1
    end
  end
 
  --[[
  Send a heartbeat periodically to port 5433. If execution is disrupted by an error then
  this script will be re-started by the 'MQTT lastlevel' resident script
  --]]
  if os.time() - heartbeat >= 10 then
    heartbeat = os.time()
    require('socket').udp():sendto('MQTTsend+'..heartbeat, '127.0.0.1', 5433)
  end
end

MQTT receive (resident, 0 sleep):

Code:

--[[
Push MQTT events to Cbus
--]]

logging = false

mqtt_broker = '192.168.9.10'
-- mqtt_username = 'YOUR_MQTT_USERNAME'
-- mqtt_password = 'YOUR_MQTT_PASSWORD'
mqtt_clientid = 'shac-receive'

mqtt_read_topic = 'cbus/read/'
mqtt_write_topic = 'cbus/write/#';

lastLevel = {}
lls = ''

function loadLastLevel()
  local llsTest = storage.get('lastLevel', '')
  if llsTest ~= lls then
    lls = llsTest
    local llt = string.split(lls, ',')
    for _, v in ipairs(llt) do
      parts = string.split(v, '=')
      lastLevel[parts[1]] = tonumber(parts[2])
    end
    end
end


function contains(prefix, text)
  pos = text:find(prefix, 1, true)
  if pos then return pos >= 1 else return false end
end


-- Load MQTT module and create new client
mqtt = require('mosquitto')
client = mqtt.new(mqtt_clientid)
status = 0


-- MQTT callbacks

client.ON_CONNECT = function(success)
  if (success) then
    log('MQTT receive connected')
    status = 1
    local mid = client:subscribe(mqtt_write_topic, 2)
  end
end

client.ON_DISCONNECT = function(...)
  log('MQTT receive disconnected')
  status = 2
end

client.ON_MESSAGE = function(mid, topic, payload)
  if logging then log(topic .. ' to ' .. payload) end

  loadLastLevel()

  local parts = string.split(topic, '/')
  local net = 0
  local app = tonumber(parts[4])
  local group = tonumber(parts[5])

  if not parts[6] then
    log('MQTT error: Invalid message format')

  elseif parts[6] == 'getall' then
    local mqttP = GetCBusByKW('MQTT', 'or')
    local mqttPs = ''
    for k, v in pairs(mqttP) do mqttPs = mqttPs..v['address'][2]..'/'..v['address'][3] end

    local datatable = grp.all()
    for key,value in pairs(datatable) do
      parts = string.split(value.address, '/')
            net = tonumber(parts[1])
            app = tonumber(parts[2])
      group = tonumber(parts[3])
        if contains(parts[2]..'/'..parts[3], mqttPs) then -- only publish groups of interest (keyword 'MQTT')
        if app == tonumber(parts[4]) and parts[3] then
          level = tonumber(value.data)
          state = (level ~= 0) and 'ON' or 'OFF'
          if logging then log(parts[3], app, group, state, level) end
          client:publish(mqtt_read_topic .. net .. '/' .. app .. '/' .. group .. '/state', state, 1, true)
          client:publish(mqtt_read_topic .. net .. '/' .. app .. '/' .. group .. '/level', level, 1, true)
        end
        end
        end

  elseif parts[6] == 'switch' then
    if payload == 'ON' then
      if logging then log('Payload is ON') end
            SetCBusLevel(0, app, group, 255, 0)
    elseif payload == 'OFF' then
      if logging then log('Payload is OFF') end
      SetCBusLevel(0, app, group, 0, 0)
    end
    
  elseif parts[6] == 'measurement' then        -- UNTESTED
        SetCBusMeasurement(0, app, group, payload, 0)
    
  elseif parts[6] == 'ramp' then
    if payload == 'OPEN' then
      if logging then log("Payload is OPEN, so using RAMP instead") end
      payload = '255'
    elseif payload == 'CLOSE' then
      if logging then log("Payload is CLOSE, so using RAMP instead") end
      payload = '0'
    elseif payload == 'STOP' then
      -- Once a blind level has been set for CBus it is set regardless of the current blind position, which is not updated like a ramp, so a stop command is nonsensical
      if logging then log("Payload is STOP, which is incompatible with CBus... ignoring") end
      do return end
    elseif payload == 'ON' then
      if contains('Fan', GetCBusGroupTag(net, app, group)) then
        if logging then log("Payload is 'Fan' ON, so using RAMP instead") end
        payload = '255'
      else
        if logging then log('Payload is ON') end
        SetCBusLevel(0, app, group, 255, 0)
        do return end
      end
    end
    if payload == 'OFF' then
      if logging then log('Payload is OFF') end
      SetCBusLevel(0, app, group, 0, 0)
    else
      local key = '0'..'/'..app..'/'..group
      parts = string.split(payload, ',')
      local lev = tonumber(parts[1])
      local num = math.floor(lev + 0.5)
      if num and num < 256 then
          if logging then log('Payload is RAMP '..payload) end
        local toSet = 0
        local ramp = 0
        if logging and lastLevel[key] then log('Last level '..lastLevel[key]) end
        if lastLevel[key] and num == 255 then
          if contains('Blindzzz', GetCBusGroupTag(net, app, group)) then -- If blind fully open is desirable instead of lastlevel, then change to actually match a 'Blind' tag
            if logging then log("Payload is 'Blind' ramp on, so ignoring lastlevel") end
            toSet = num
          else
              toSet = lastLevel[key]
          end
        else
          toSet = num
        end
        if parts[2] ~= nil then ramp = tonumber(parts[2]) else ramp = 0 end
                SetCBusLevel(0, app, group, toSet, ramp)
      end
    end
  end
end


-- client:login_set(mqtt_username, mqtt_password)
client:connect(mqtt_broker, 1883, 25)
client:loop_forever()

MQTT lastlevel (resident, 0 sleep):

Code:

--[[
Maintain Cbus 'lastlevels'

Used so that MQTT 'on'/ ramp 255 events can return a light/fan/blind to the last known set level.

Also monitors keepalive messages from 'MQTT send', and disables/enables that script should it fail for whatever reason.
--]]

logging = false

server = require('socket').udp()
server:settimeout(0.5)
server:setsockname('127.0.0.1', 5433)

lastLevel = {}
receivedOff = {}
rampDetect = {}
lastSaved = os.time()

function loadLastLevel()
    lls = storage.get('lastLevel', '')
  llt = string.split(lls, ',')
  for _, v in ipairs(llt) do
    parts = string.split(v, '=')
    lastLevel[parts[1]] = tonumber(parts[2])
  end
end

function saveLastLevel()
  local ll = {}
  for k, v in pairs(lastLevel) do
    table.insert(ll, k..'='..v)
  end
  table.sort(ll)
  local lls = table.concat(ll, ',')
  old = storage.get('lastLevel', '')
  if lls ~= old then
      storage.set('lastLevel', lls)
    log('Saved last levels')
  end
end

function processCommand(cmd)
    if logging then log('Command received: '..cmd) end
  local parts = string.split(cmd, '/')
  if not parts[1] or not parts[2] or not parts[3] or not parts[4] then
    do return end
  end
  local key = parts[1]..'/'..parts[2]..'/'..parts[3]
  local level = tonumber(parts[4])
  if level == 0 then
    if not receivedOff[key] or (receivedOff[key] and os.time() - receivedOff[key] >= 30) then
      receivedOff[key] = os.time()
      rampDetect[key] = nil
      if logging then log('Executing OFF ' .. key) end
      if logging then
        if receivedOff[key] then log('Last received OFF '..receivedOff[key]..' more than 30 seconds ago') else log('Last received OFF never') end
      end
    end
  else
    if logging then log('Executing ON ' .. key) end
    local ll = 0
    if not rampDetect[key] then
      rampDetect[key] = level
    end
    if receivedOff[key] and (os.time() - receivedOff[key] < 30) then
      if logging then log('Last received OFF '..receivedOff[key]..' within 30 seconds') end
      if level > rampDetect[key] then -- must be ramping on
        ll = level
      end
    end
    if not receivedOff[key] or (os.time() - receivedOff[key] > 30) then
      if logging then log('Last received off key does not exist or off key is older than 30 seconds') end
      ll = level
    end
    if ll > 0 then
      if logging then log('Saving lastlevel of '..level) end
      lastLevel[key] = ll
    end
  end
end

function contains(prefix, text)
  pos = text:find(prefix, 1, true)
  if pos then return pos >= 1 else return false end
end

loadLastLevel()

log('MQTT lastlevel initialised')

-- Loop looking for lastlevel values
while true do
  cmd = server:receive()
    if cmd and type(cmd) == 'string' then
    if contains('/', cmd) then
        processCommand(cmd)
    elseif contains('+', cmd) then
      parts = string.split(cmd, '+')
      if parts[1] == 'MQTTsend' then
          MQTTsendHeartbeat = tonumber(parts[2])
      end
    end
  end
 
  if os.time() - lastSaved > 2 then
    saveLastLevel()
    lastSaved = os.time()
  end

  --[[
  Heartbeats:
 
  The MQTT send script infinite loop occasionally fails, stopping that script. To ensure it
  gets restarted without intervention, this script listens for a heartbeat from it every ten
  seconds. If two consecutive heartbeats are not received then that script is disabled and re-
  enabled.
  --]]
 
  -- If last heartbeat is nil (i.e. not yet received) then initialise it
  if not MQTTsendHeartbeat then
    MQTTsendHeartbeat = os.time()
  end
 
  MQTTsendSecondsSince = os.time() - MQTTsendHeartbeat
  if MQTTsendSecondsSince > 20 then -- Missed two heartbeats, so re-start script
    log('Missed MQTT send heartbeat (last received '..MQTTsendSecondsSince..' seconds ago) - Re-starting MQTT send')
    script.disable('MQTT send')
    script.enable('MQTT send')
    MQTTsendHeartbeat = nil
  end
end

 

So to continue this thread of chatting amongst myself, I've had to make some changes to ensure reliability.

The first relates to how the 'last level' of groups are detected. The previous method was messed up by groups ramping on. Nothing broke, but last levels were repeatedly saved during the ramp. The code below fixes this.

The second relates to occasional MQTT disconnects, and how this is handled. Some changes were required to ensure that any restart of the MQTT broker was handled well, and also for any failure of the SHAC send script given it uses an infinite loop.

And the third is the saving of 'last levels' to storage, which should only happen when a change is made. Sorting the list was required prior to old value comparison to prevent some 'false saves' because of LUA not guaranteeing list order.

It's been a week of running perfectly, with broker restarted a few times, and much house activity.

Enjoy. I'm delighted with the result.

Event-based 'MQTT' script, on required groups having a 'MQTT' label:

Code:

--[[
Pushes CBus events to MQTT resident scripts via internal sockets.

Tag required objects with the "MQTT" keyword and this script will run whenever one of those objects change.

It seems that this script must be disabled/enabled to enable it to be tied to new objects assigned the MQTT keyword.
--]]

-- Send an event to publish to broker
require('socket').udp():sendto(event.dst .. "/" .. event.getvalue(), '127.0.0.1', 5432)

-- Send an event to monitor for lastlevel
require('socket').udp():sendto(event.dst, '127.0.0.1', 5433)

'MQTT send' resident, zero sleep. Modify tag translation for publishing to the broker using preferred names, as yours definitely will not match mine:

Code:

--[[
Push CBus events to MQTT
--]]

logging = false

socketTimeout = 0.4 -- Timeout should not be any less to ensure reliability
mqttBroker = '192.168.9.10'
-- Un-comment and set values for authentication if needed for the broker
-- mqttUsername = 'YOUR_mqttUsername'
-- mqttPassword = 'YOUR_mqttPassword'
mqttClientId = 'shac-send'

mqttReadTopic = 'cbus/read/'
mqttDiscoveryTopic = 'cbus'

socket = require('socket')

unpublished = {}
toPublish = 0
published = 0
notify = true
status = 0

function publishCurrent()
  local mqttP = {}
  retry = 3
  while retry > 0 do -- Very occasionally GetCBusByKW will return no results, so retry three times
    mqttP = GetCBusByKW('MQTT', 'or')
    if #mqttP > 0 then
      retry = 0
    else
      socket.sleep(1)
      retry = retry - 1
    end
  end
 
  n = 1
  for k, v in pairs(mqttP) do
    app = tonumber(v['address'][2])
    group = tonumber(v['address'][3])
    unpublished[n] = {app=app, group=group}
    n = n + 1
  end
  toPublish = n - 1
  published = 0
  log('Queued '..toPublish..' objects with keyword MQTT for publication')
end

function begins(prefix, text)
  pos = text:find(prefix, 1, true)
  if pos then return pos == 1 else return false end
end

function contains(prefix, text)
  pos = text:find(prefix, 1, true)
  if pos then return pos >= 1 else return false end
end

mqtt = require('mosquitto')
client = mqtt.new(mqttClientId)
server = require('socket').udp()
server:settimeout(socketTimeout)
server:setsockname('127.0.0.1', 5432)

client.ON_CONNECT = function(success)
  if success then
    log('MQTT send connected')
    status = 1
    publishCurrent()
  end
end

client.ON_DISCONNECT = function(...)
  log('MQTT send disconnected')
  notify = true
  status = 2
end

if mqttUsername then
  client:login_set(mqttUsername, mqttPassword)
end
client:connect(mqttBroker, 1883, 25)
client:loop_start()

function publish(net, app, group, level)
  if contains('Blind', GetCBusGroupTag(0, app, group)) then
    -- state = (level ~= 0) and 'open' or 'closed'
    state = 'stopped'
  else
    state = (level ~= 0) and 'ON' or 'OFF'
  end
  client:publish(mqttReadTopic..net..'/'..app..'/'..group..'/state', state, 1, true)
  client:publish(mqttReadTopic..net..'/'..app..'/'..group..'/level', level, 1, true)
  if logging then log('Publishing state and level '..mqttReadTopic..net..'/'..app..'/'..group..' to '..state..'/'..level) end
end

function unpublish(net, app, group)
  client:publish(mqttReadTopic..net..'/'..app..'/'..group..'/state', '', 1, true)
  client:publish(mqttReadTopic..net..'/'..app..'/'..group..'/level', '', 1, true)
  if logging then log('Un-publishing state and level '..mqttReadTopic..net..'/'..app..'/'..group) end
end

function addDiscover(net, app, group)
  local name = GetCBusGroupTag(0, app, group)
  local sa = ''
  local img = ''
  local dType = ''
  local preferName = ''

  -- Set suggested area
  if     begins('Kitchen', name) then sa = 'Kitchen'
  elseif begins('Family', name) then sa = 'Family Room'
  elseif begins('Formal', name) then sa = 'Front Lounge'
  elseif begins('Dining', name) then sa = 'Dining Room'
  elseif begins('Bedroom 1', name) then sa = 'Bedroom 1'
  elseif begins('Bedroom 2', name) then sa = 'Bedroom 2'
  elseif begins('Bedroom 3', name) then sa = 'Bedroom 3'
  elseif begins('Bathroom 1', name) then sa = 'Bathroom 1'
  elseif begins('Bathroom 2', name) then sa = 'Bathroom 2'
  elseif begins('Hall', name) then sa = 'Hall'
  elseif begins('Den', name) then sa = 'Den'
  elseif begins('Laundry', name) then sa = 'Den'
  elseif begins('Outside', name) then sa = 'Outside'
  elseif contains('Storage', name) then sa = 'Store'
  elseif begins('Hutch Bathroom', name) then sa = 'Hutch Bathroom'
  elseif begins('Hutch Kitchen', name) then sa = 'Hutch Kitchen'
  elseif begins('Hutch', name) then sa = 'Hutch'
  elseif begins('Open', name) then sa = 'Outside'
  elseif begins('Close', name) then sa = 'Outside'
  elseif begins('Pool', name) then sa = 'Pool'
  elseif begins('Spa', name) then sa = 'Pool'
  else sa = 'Unknown'
  end

  -- Set image
  if     contains('Pool Heat', name) then img = 'mdi:pump'
  elseif contains('Heat', name) then img = 'mdi:radiator'
  elseif contains('Pump', name) then img = 'mdi:pump'
  elseif contains('Blower', name) then img = 'mdi:chart-bubble'
  elseif contains('Gate', name) and contains('Open', name) then img = 'mdi:gate-open'
  elseif contains('Gate', name) and contains('Close', name) then img = 'mdi:gate'
  elseif contains('Sensors', name) then img = 'mdi:motion-sensor-off'
  elseif contains('Sweep Fan', name) then img =  'mdi:ceiling-fan'
  elseif contains('Fan', name) then img = 'mdi:fan'
  elseif contains('Rail Enable', name) then img = 'mdi:radiator-disabled'
  elseif contains('Towel Rail', name) then img = 'mdi:radiator'
  elseif contains('Floor Enable', name) then img = 'mdi:radiator-disabled'
  elseif contains('Under Floor', name) then img = 'mdi:radiator'
  elseif contains('Blind', name) then img = 'mdi:blinds'
  else img = 'mdi:lightbulb'
  end

  -- Set type of device
  if img == 'mdi:lightbulb' then dType = 'light'
  elseif img == 'mdi:ceiling-fan' then dType = 'fan'
  elseif img == 'mdi:blinds' then dType = 'cover'
  else dType = 'switch' end

  -- Adjust the device name
  if     contains('Pantry LV', name) then preferName = sa..' Pantry Light'
  elseif contains('Dining LV', name) then preferName = sa..' Perimeter Lights'
  elseif contains('Formal LV', name) then preferName = sa..' Perimeter Lights'
  elseif contains('Bedroom 2', name) then preferName = sa..' Light'
  elseif contains('Bedroom 3', name) then preferName = sa..' Light'
  elseif contains('Hall Front', name) then preferName = 'Front Hall'
  elseif contains('Hall Mid', name) then preferName = 'Hall'
  elseif contains('Floor Enable',name) then preferName = sa..' Under Floor Heating Enable'
  elseif contains('Under Floor', name) then preferName = sa..' Under Floor Heating'
  elseif contains('Kitchen', name) and contains('LV', name) then preferName = sa..' Main Lights'
  elseif contains('Bathroom 2', name) and contains('LV 1', name) then preferName = sa..' Main Lights'
  elseif contains('Bathroom 2', name) and contains('LV 2', name) then preferName = sa..' Spa Lights'
  elseif contains('Laundry', name) and not contains('Outside', name) then preferName = 'Laundry Lights'
  elseif contains('Bedroom 1 LV', name) then preferName = sa..' Wardrobe Lights'
  elseif contains('Dining Garden', name) then preferName = 'Outside Cat Hutch Light'
  elseif contains('Verandah Pendant', name) then preferName = 'Verandah Light'
  elseif contains('Verandah LV', name) then preferName = 'Verandah Perimeter Lights'
  elseif contains('Hutch Bathroom', name) then preferName = sa..' Main Light'
  elseif contains('Hutch Kitchen', name) then preferName = 'Galley Lights'
  elseif contains('Central', name) then preferName = sa..' Central Light'
  elseif contains('Hutch Perimeter', name) then preferName = sa..' Perimeter Lights'
  elseif contains('Hutch Shrubbery', name) then preferName = sa..' Shrubbery Lights'
  elseif contains('Hutch Storage', name) then preferName = 'Store Light'
  elseif contains('BBQ', name) then preferName = sa..' BBQ Light'
  elseif contains('Store Flood', name) then preferName = sa..' Store Flood Light'
  elseif contains('Side Door', name) then preferName = sa..' Side Door Light'
  elseif contains('Laundry Door', name) then preferName = sa..' Laundry Door Light'
  elseif contains('Heat 1', name) then preferName = 'Pool Side Heater 1'
  elseif contains('Heat 2', name) then preferName = 'Pool Side Heater 2'
  elseif contains('Heat 3', name) then preferName = 'TV Side Heater 1'
  elseif contains('Heat 4', name) then preferName = 'TV Side Heater 2'
  elseif contains('Pendant', name) then preferName = sa..' Main Light'
  elseif contains('LV', name) then preferName = sa..' Main Lights'
  elseif dType == 'light' then preferName = name..' Lights'
  else preferName = name
  end

  if logging then log('Publish discovery '..name..' as '..dType..':'..preferName..' in area '..sa) end

  oid = 'cbus_mqtt_'..net..'_'.. app..'_'.. group

  if dType == 'light' then
    payload = {
      ['name'] = preferName,
      ['unique_id'] = oid,
      ['ic'] = img,
      ['dev'] = {
        ['ids'] = oid,
        ['sa'] = sa
      },
      ['stat_t'] = 'cbus/read/'..net..'/'..app..'/'..group..'/state',
      ['cmd_t'] = 'cbus/write/'..net..'/'..app..'/'..group..'/switch',
      ['bri_stat_t'] = 'cbus/read/'..net..'/'..app..'/'..group..'/level',
      ['bri_cmd_t'] = 'cbus/write/'..net..'/'..app..'/'..group..'/ramp',
      ['pl_off'] = 'OFF',
      ['on_cmd_type'] = 'brightness',
    }
  elseif dType == 'switch' then
    payload = {
      ['name'] = preferName,
      ['unique_id'] = oid,
      ['ic'] = img,
      ['dev'] = {
        ['ids'] = oid,
        ['sa'] = sa
      },
      ['stat_t'] = 'cbus/read/'..net..'/'..app..'/'..group..'/state',
      ['cmd_t'] = 'cbus/write/'..net..'/'..app..'/'..group..'/switch',
      ['pl_on'] = 'ON',
      ['pl_off'] = 'OFF',
    }
  elseif dType == 'fan' then
    payload = {
      ['name'] = preferName,
      ['unique_id'] = oid,
      ['ic'] = img,
      ['dev'] = {
        ['ids'] = oid,
        ['sa'] = sa
      },
      ['stat_t'] = 'cbus/read/'..net..'/'..app..'/'..group..'/state',
      ['cmd_t'] = 'cbus/write/'..net..'/'..app..'/'..group..'/ramp',
      ['pl_on'] = 'ON',
      ['pl_off'] = 'OFF',
      ['pr_mode_cmd_t'] = 'cbus/write/'..net..'/'..app..'/'..group..'/ramp',
      ['pr_mode_cmd_tpl'] = '{% if value == "low" %} 86 {% elif value == "medium" %} 170 {% elif value == "high" %} 255 {% endif %}',
      ['pr_mode_stat_t'] = 'cbus/read/'..net..'/'..app..'/'..group..'/level',
      ['pr_mode_val_tpl'] = '{% if value == 0 %} OFF {% elif value == 86 %} low {% elif value == 170 %} medium {% elif value == 255 %} high {% endif %}',
      ['pr_modes'] = {'low', 'medium', 'high'}
    }
  elseif dType == 'cover' then
    payload = {
      ['name'] = preferName,
      ['unique_id'] = oid,
      ['ic'] = img,
      ['dev'] = {
        ['ids'] = oid,
        ['sa'] = sa
      },
      ['stat_t'] = 'cbus/read/'..net..'/'..app..'/'..group..'/state',
      ['cmd_t'] = 'cbus/write/'..net..'/'..app..'/'..group..'/ramp',
      ['pos_open'] = 255,
      ['pos_clsd'] = 0,
      ['pl_open'] = 'OPEN',
      ['pl_cls'] = 'CLOSE',
      ['pos_t'] = 'cbus/read/'..net..'/'..app..'/'..group..'/level',
      ['set_pos_t'] = 'cbus/write/'..net..'/'..app..'/'..group..'/ramp',
    }
  end

  local j = json.encode(payload)
  local topic = mqttDiscoveryTopic..'/'..dType..'/'..oid..'/config'

  if sa == 'changeme' then -- Alter 'changeme' to an area name to remove all topics in that area instead of publishing - for debug
    client:publish(topic, '', 1, true)
  else
    client:publish(topic, j, 1, true)
  end
end

heartbeat = os.time()

while true do
  cmd = server:receive()
  if cmd and type(cmd) == 'string' then
    parts = string.split(cmd, '/')
    publish(254, tonumber(parts[2]), tonumber(parts[3]), tonumber(parts[4]))
  end

  if #unpublished > 0 then
    if notify then
      log('Publishing discovery and current level topics')
      notify = false
    end
    addDiscover(254, unpublished[1].app, unpublished[1].group)
    publish(254, unpublished[1].app, unpublished[1].group, GetCBusLevel(0, unpublished[1].app, unpublished[1].group))
    table.remove(unpublished, 1)
    published = published + 1
    if #unpublished == 0 then log('Publishing completed for '..published..' discovery and current level topics') end
  end

  --[[
  Send a heartbeat periodically to port 5433. If execution is disrupted by an error then
  this script will be re-started by the 'MQTT lastlevel' resident script
  --]]
  local stat, err = pcall(function ()
    if os.time() - heartbeat >= 10  and status ~= 2 then
      heartbeat = os.time()
      require('socket').udp():sendto('MQTTsend+'..heartbeat, '127.0.0.1', 5433)
    end
  end)
  if not stat then -- If sending the heartbeat faults then exit the loop - the script will re-start
    log('A fault occurred sending heartbeat. Restarting...')
    do return end
  end
end

'MQTT receive' resident, zero sleep:

Code:

--[[
Push MQTT events to CBus
--]]

logging = false

mqttBroker = '192.168.9.10'
-- Un-comment and set values for authentication if needed for the broker
-- mqttUsername = 'YOUR_mqttUsername'
-- mqttPassword = 'YOUR_mqttPassword'
mqttClientId = 'shac-receive'

mqttReadTopic = 'cbus/read/'
mqttWriteTopic = 'cbus/write/#';

lastLevel = {}
lls = ''

function loadLastLevel()
  local llsTest = storage.get('lastLevel', '')
  if llsTest ~= lls then
    lls = llsTest
    local llt = string.split(lls, ',')
    for _, v in ipairs(llt) do
      parts = string.split(v, '=')
      lastLevel[parts[1]] = tonumber(parts[2])
    end
  end
end


function contains(prefix, text)
  pos = text:find(prefix, 1, true)
  if pos then return pos >= 1 else return false end
end


-- Load MQTT module and create new client
mqtt = require('mosquitto')
client = mqtt.new(mqttClientId)
status = 0


-- MQTT callbacks

client.ON_CONNECT = function(success)
  if (success) then
    log('MQTT receive connected')
    status = 1
    local mid = client:subscribe(mqttWriteTopic, 2)
  end
end

client.ON_DISCONNECT = function(...)
  log('MQTT receive disconnected')
  status = 2
end

client.ON_MESSAGE = function(mid, topic, payload)
  if logging then log(topic .. ' to ' .. payload) end

  loadLastLevel()

  local parts = string.split(topic, '/')
  local net = 0
  local app = tonumber(parts[4])
  local group = tonumber(parts[5])

  if not parts[6] then
    log('MQTT error: Invalid message format')

  elseif parts[6] == 'getall' then
    local mqttP = GetCBusByKW('MQTT', 'or')
    local mqttPs = ''
    for k, v in pairs(mqttP) do mqttPs = mqttPs..v['address'][2]..'/'..v['address'][3] end

    local datatable = grp.all()
    for key,value in pairs(datatable) do
      parts = string.split(value.address, '/')
      net = tonumber(parts[1])
      app = tonumber(parts[2])
      group = tonumber(parts[3])
      if contains(parts[2]..'/'..parts[3], mqttPs) then -- only publish groups of interest (keyword 'MQTT')
        if app == tonumber(parts[4]) and parts[3] then
          level = tonumber(value.data)
          state = (level ~= 0) and 'ON' or 'OFF'
          if logging then log(parts[3], app, group, state, level) end
          client:publish(mqttReadTopic .. net .. '/' .. app .. '/' .. group .. '/state', state, 1, true)
          client:publish(mqttReadTopic .. net .. '/' .. app .. '/' .. group .. '/level', level, 1, true)
        end
      end
    end

  elseif parts[6] == 'switch' then
    if payload == 'ON' then
      if logging then log('Payload is ON') end
      SetCBusLevel(0, app, group, 255, 0)
    elseif payload == 'OFF' then
      if logging then log('Payload is OFF') end
      SetCBusLevel(0, app, group, 0, 0)
    end
  
  elseif parts[6] == 'measurement' then    -- UNTESTED
    SetCBusMeasurement(0, app, group, payload, 0)

  elseif parts[6] == 'ramp' then
    if payload == 'OPEN' then
      if logging then log("Payload is OPEN, so using RAMP instead") end
      payload = '255'
    elseif payload == 'CLOSE' then
      if logging then log("Payload is CLOSE, so using RAMP instead") end
      payload = '0'
    elseif payload == 'STOP' then
      -- Once a blind level has been set for CBus it is set regardless of the current blind position, which is not updated like a ramp, so a stop command is nonsensical
      if logging then log("Payload is STOP, which is incompatible with CBus... ignoring") end
      do return end
    elseif payload == 'ON' then
      if contains('Fan', GetCBusGroupTag(net, app, group)) then
        if logging then log("Payload is 'Fan' ON, so using RAMP instead") end
        payload = '255'
      else
        if logging then log('Payload is ON') end
        SetCBusLevel(0, app, group, 255, 0)
        do return end
      end
    end
    if payload == 'OFF' then
      if logging then log('Payload is OFF') end
      SetCBusLevel(0, app, group, 0, 0)
    else
      local key = '0'..'/'..app..'/'..group
      parts = string.split(payload, ',')
      local lev = tonumber(parts[1])
      local num = math.floor(lev + 0.5)
      if num and num < 256 then
        if logging then log('Payload is RAMP '..payload) end
        local toSet = 0
        local ramp = 0
        if logging and lastLevel[key] then log('Last level '..lastLevel[key]) end
        if lastLevel[key] and num == 255 then
          if contains('Blindzzz', GetCBusGroupTag(net, app, group)) then -- If blind fully open is desirable instead of lastlevel, then change to actually match a 'Blind' tag
            if logging then log("Payload is 'Blind' ramp on, so ignoring lastlevel") end
            toSet = num
          else
            toSet = lastLevel[key]
          end
        else
          toSet = num
        end
        if parts[2] ~= nil then ramp = tonumber(parts[2]) else ramp = 0 end
        SetCBusLevel(0, app, group, toSet, ramp)
      end
    end
  end
end


if mqttUsername then
  client:login_set(mqttUsername, mqttPassword)
end
client:connect(mqttBroker, 1883, 25)
client:loop_forever()

And finally, 'MQTT lastlevel' resident, zero sleep:

Code:

--[[
Maintain CBus 'lastlevels'

Used so that MQTT 'on' events can return a light/fan/blind to the last known set level.

Also monitors keepalive messages from 'MQTT send', and disables/enables that script should it fail for whatever reason.
--]]

function loadLastLevel()
  lls = storage.get('lastLevel', '')
  llt = string.split(lls, ',')
  for _, v in ipairs(llt) do
    parts = string.split(v, '=')
    lastLevel[parts[1]] = tonumber(parts[2])
  end
end

if not initialised then
  logging = false

  server = require('socket').udp()
  server:settimeout(0.5)
  server:setsockname('127.0.0.1', 5433)

  monitoring = {}
  iterations = {}
  last = {}

  lastLevel = {}
  loadLastLevel()

  log('MQTT lastlevel initialised')

  initialised = true
end

function saveLastLevel()
  local ll = {}
  for k, v in pairs(lastLevel) do
    table.insert(ll, k..'='..v)
  end
  table.sort(ll)
  local lls = table.concat(ll, ',')
  old = storage.get('lastLevel', '')
  if lls ~= old then
    storage.set('lastLevel', lls)
    log('Saved last levels')
  end
end


remove = {}

for g, ts in pairs(monitoring) do
  parts = string.split(g, '/')
  net = tonumber(parts[1])
  app = tonumber(parts[2])
  grp = tonumber(parts[3])
  current = GetCBusLevel(net, app, grp)

  -- If the monitored group stays at the same level for six iterations then it's a stable value and not ramping (0.5s per iteration)
  if current == last[g] then
    if iterations[g] > 6 then
      table.insert(remove, g)
      if current > 0 then -- If the stable value is non-zero then save it as the lastLevel
        lastLevel[g] = current
        if logging then log('Setting lastLevel to '..current..' for '..g) end
        saveLastLevel()
      end
    else
      iterations[g] = iterations[g] + 1
    end
  else
    iterations[g] = 0 -- Level changed, so reset
    last[g] = current
  end
 
  if os.time() - ts > 30 then -- Level has been changing for more than 30 seconds, so terminate the monitor
    if logging then log('Terminating monitor for '..g..' (30 second timeout)') end
    table.insert(remove, g)
  end
end

for i=1,#remove do
  if logging then log('Stopping monitor for '..remove[i]..' at '..os.time()) end
  monitoring[remove[i]] = nil -- Clean up removed monitors
  iterations[remove[i]] = nil
  last[remove[i]] = nil
end


function contains(prefix, text)
  pos = text:find(prefix, 1, true)
  if pos then return pos >= 1 else return false end
end

-- Look for lastlevel values
cmd = server:receive()
if cmd and type(cmd) == 'string' then

  -- If the command contains a slash it's to start monitoring a group
  if contains('/', cmd) then
    -- processCommand(cmd)
    if not monitoring[cmd] then
      last[cmd] = -1
      iterations[cmd] = 0
      monitoring[cmd] = os.time()
      if logging then log('Starting monitor for '..cmd..' at '..os.time()) end
    end

  -- If it contains a plus then it's a heartbeat
  elseif contains('+', cmd) then
    parts = string.split(cmd, '+')
    if parts[1] == 'MQTTsend' then
      MQTTsendHeartbeat = tonumber(parts[2])
    end
  end
end


--[[
Heartbeats:

The MQTT send script infinite loop can fail, stopping that script. To ensure it gets
restarted without intervention, this script listens for a heartbeat from it every ten
seconds. If two consecutive heartbeats are not received then that script is disabled
and re-enabled.
--]]

-- If last heartbeat is nil (i.e. not yet received) then initialise it
if not MQTTsendHeartbeat then
  MQTTsendHeartbeat = os.time()
end

MQTTsendSecondsSince = os.time() - MQTTsendHeartbeat
if MQTTsendSecondsSince > 20 then -- Missed two heartbeats, so re-start script
  log('Missed two MQTT send heartbeats (last received '..MQTTsendSecondsSince..' seconds ago) - Re-starting MQTT send')
  script.disable('MQTT send')
  script.enable('MQTT send')
  MQTTsendHeartbeat = nil
end

 

In a further development, I think this is quite a good generic approach to MQTT discovery.

In short, I use a series of keywords tagged to each group of interest in the SHAC to allow setting of Home Assistant preferred name, image, type of discovery topic and more. The script polls every ten seconds for changes and applies create/remove/update messages to the MQTT broker.

If preferred name isn't set it will use name. Default scale = 1, default decimal places = 2, default image and unit = none.

MQTT send (sleep zero)...

Code:

--[[
Push CBus events to MQTT, and publish discovery topics

Add the keyword 'MQTT' to groups for discovery, plus...

  One of  light, fan, cover, sensor or switch
  Plus...
  sa=     Suggested area
  img=    Image
  pn=     Preferred name
  dec=    Decimal places
  unit=   Unit of measurement
  scale=  Multiplier / divider

Examples:

MQTT, light, sa=Outside, pn=Outside Laundry Door Light, img=mdi:lightbulb,
MQTT, switch, sa=Outside, img=mdi:gate-open,
MQTT, fan, sa=Hutch, img=mdi:ceiling-fan,
MQTT, cover, sa=Bathroom 2, img=mdi:blinds,
MQTT, sensor, sa=Pool, pn=Pool Pool Temperature, unit= °C, dec=1,
MQTT, sensor, sa=Pool, pn=Pool Level, unit= mm, dec=0, scale=1000,
--]]

logging = false

socketTimeout = 0.5 -- Timeout should not be any less to ensure reliability as lower values can cause script lock-up for some reason...
mqttBroker = '192.168.10.21'
mqttUsername = 'mqtt'
mqttPassword = 'password'
mqttClientId = 'shac-send'

mqttReadTopic = 'cbus/read/'
mqttDiscoveryTopic = 'cbus'

socket = require('socket')

covers = {}
publishAdj = {}
unpublished = {}
toPublish = 0
published = 0
notify = true
status = 0

allgrps = grp.all()

function publishCurrent()
  local mqttP = {}
  mqttP = GetCBusByKW('MQTT', 'or')
  n = 1
  for k, v in pairs(mqttP) do
    app = tonumber(v['address'][2])
    group = tonumber(v['address'][3])
    if v['address'][4] ~= nil then channel = tonumber(v['address'][4]) else channel = nil end
    unpublished[n] = {app=app, group=group, channel=channel}
    n = n + 1
  end
  toPublish = n - 1
  published = 0
  log('Queued '..toPublish..' objects with keyword MQTT for publication')
  status = 3
end

function begins(prefix, text)
  pos = text:find(prefix, 1, true)
  if pos then return pos == 1 else return false end
end

function contains(prefix, text)
  pos = text:find(prefix, 1, true)
  if pos then return pos >= 1 else return false end
end

mqtt = require('mosquitto')
client = mqtt.new(mqttClientId)
server = require('socket').udp()
server:settimeout(socketTimeout)
server:setsockname('127.0.0.1', 5432)

client.ON_CONNECT = function(success)
  if success then
    log('MQTT send connected')
    status = 1
    publishCurrent()
  end
end

client.ON_DISCONNECT = function(...)
  log('MQTT send disconnected')
  notify = true
  status = 2
end

if mqttUsername then
  client:login_set(mqttUsername, mqttPassword)
end
client:connect(mqttBroker, 1883, 25)
client:loop_start()

function publish(net, app, group, level)
  if covers[net..'/'..app..'/'..group] then
    state = 'stopped' -- For CBus blind controllers
  else
    state = (level ~= 0) and 'ON' or 'OFF'
  end
  client:publish(mqttReadTopic..net..'/'..app..'/'..group..'/state', state, 1, true)
  client:publish(mqttReadTopic..net..'/'..app..'/'..group..'/level', level, 1, true)
  if logging then log('Publishing state and level '..mqttReadTopic..net..'/'..app..'/'..group..' to '..state..'/'..level) end
end

function publishMeasurement(net, app, group, channel, value)
  local adjust = publishAdj[net..'/'..app..'/'..group..'/'..channel]
  if adjust then v = tonumber(string.format('%.'..adjust['dec']..'f', value * adjust['scale'])) else v = value end
  client:publish(mqttReadTopic..net..'/'..app..'/'..group..'_'..channel..'/state', v, 1, true)
  if logging then log('Publishing measurement '..mqttReadTopic..net..'/'..app..'/'..group..'_'..channel..' to '..v) end
end


function addDiscover(net, app, group, channel)
  local name = GetCBusGroupTag(0, app, group)
  if not name then name = '' end
  local pn = name
  local sa = ''
  local img = ''
  local units = ''
  local scale = 1
  local decimals = 2
  local dType = ''
  local preferName = ''
  local tagcache = ''

  -- Build an alias to refer to each group
  alias = '0'..'/'..app..'/'..group;  if channel then alias = alias..'/'..channel end

  -- Find the keywords (aka tagcache) for the group
  for _, v in ipairs(allgrps) do
    if v['address'] == alias then
      tagcache = v['tagcache']
      break
    end
  end

  -- Extract MQTT topic settings
  tags = string.split(tagcache, ', ')
  for _, t in ipairs(tags) do
    tp = string.split(t, '=')
    if tp[2] then
      if tp[1] == 'sa' then sa = tp[2]
      elseif tp[1] == 'pn' then pn = tp[2]
      elseif tp[1] == 'img' then img = tp[2]
      elseif tp[1] == 'unit' then units = tp[2]
      elseif tp[1] == 'dec' then decimals = tonumber(tp[2])
      elseif tp[1] == 'scale' then scale = tonumber(tp[2])
      end
    else
      if tp[1] ~= 'MQTT' then dType = tp[1] end
    end
  end
 
  if logging then log('Publish discovery '..name..' as '..dType..':'..preferName..' in area '..sa) end

  -- Build an OID (measurement application gets a channel as well)
  if not channel then
    oid = 'cbus_mqtt_'..net..'_'.. app..'_'..group
  else
    oid = 'cbus_mqtt_'..net..'_'.. app..'_'..group..'_'..channel
  end

  -- Build the type-specific payload to publish
  if dType == 'light' then
    payload = {
      ['stat_t'] = 'cbus/read/'..net..'/'..app..'/'..group..'/state',
      ['cmd_t'] = 'cbus/write/'..net..'/'..app..'/'..group..'/switch',
      ['bri_stat_t'] = 'cbus/read/'..net..'/'..app..'/'..group..'/level',
      ['bri_cmd_t'] = 'cbus/write/'..net..'/'..app..'/'..group..'/ramp',
      ['pl_off'] = 'OFF',
      ['on_cmd_type'] = 'brightness',
    }
  elseif dType == 'switch' then
    payload = {
      ['stat_t'] = 'cbus/read/'..net..'/'..app..'/'..group..'/state',
      ['cmd_t'] = 'cbus/write/'..net..'/'..app..'/'..group..'/switch',
      ['pl_on'] = 'ON',
      ['pl_off'] = 'OFF',
    }
  elseif dType == 'fan' then
    payload = {
      ['stat_t'] = 'cbus/read/'..net..'/'..app..'/'..group..'/state',
      ['cmd_t'] = 'cbus/write/'..net..'/'..app..'/'..group..'/ramp',
      ['pl_on'] = 'ON',
      ['pl_off'] = 'OFF',
      ['pr_mode_cmd_t'] = 'cbus/write/'..net..'/'..app..'/'..group..'/ramp',
      ['pr_mode_cmd_tpl'] = '{% if value == "low" %} 86 {% elif value == "medium" %} 170 {% elif value == "high" %} 255 {% endif %}',
      ['pr_mode_stat_t'] = 'cbus/read/'..net..'/'..app..'/'..group..'/level',
      ['pr_mode_val_tpl'] = '{% if value == 0 %} OFF {% elif value == 86 %} low {% elif value == 170 %} medium {% elif value == 255 %} high {% endif %}',
      ['pr_modes'] = {'low', 'medium', 'high'}
    }
  elseif dType == 'cover' then
    payload = {
      ['stat_t'] = 'cbus/read/'..net..'/'..app..'/'..group..'/state',
      ['cmd_t'] = 'cbus/write/'..net..'/'..app..'/'..group..'/ramp',
      ['pos_open'] = 255,
      ['pos_clsd'] = 0,
      ['pl_open'] = 'OPEN',
      ['pl_cls'] = 'CLOSE',
      ['pos_t'] = 'cbus/read/'..net..'/'..app..'/'..group..'/level',
      ['set_pos_t'] = 'cbus/write/'..net..'/'..app..'/'..group..'/ramp',
    }
  elseif dType == 'sensor' then
    payload = {
      ['stat_t'] = 'cbus/read/'..net..'/'..app..'/'..group..'_'..channel..'/state',
    }
  end

  -- Add payload common to all
  payload['name'] = pn
  payload['uniq_id'] = oid
  payload['dev'] = { ['ids'] = oid, ['sa'] = sa, ['mf'] = 'Schneider Electric', ['mdl'] = 'CBus' }
  if img ~= '' then payload['ic'] = img end
  if units ~= '' then payload['unit_of_meas'] = units end

  local j = json.encode(payload)
  local topic = mqttDiscoveryTopic..'/'..dType..'/'..oid..'/config'

  client:publish(topic, j, 1, true)
 
  -- Adjust alias for CBus local network
  alias = '254'..'/'..app..'/'..group
  if channel then alias = alias..'/'..channel end

  if decimals ~= 2 or scale ~= 1 then publishAdj[alias] = { ['dec'] = decimals, ['scale'] = scale } end
  if dType == 'cover' then covers[alias] = true end
end


heartbeat = os.time()
tagcaches = 0

while true do
  cmd = server:receive()
  if cmd and type(cmd) == 'string' then
    parts = string.split(cmd, '/')
    if not parts[5] then
      publish(254, tonumber(parts[2]), tonumber(parts[3]), tonumber(parts[4]))
    else
      publishMeasurement(254, tonumber(parts[2]), tonumber(parts[3]), tonumber(parts[4]), tonumber(parts[5]))
    end
  end

  -- Add/update/delete MQTT items
  if os.time() - tagcaches >= 10 and #unpublished == 0 and status == 3 then
    if currTagcache then
      tagcaches = os.time()
      allgrps = grp.all()
      -- Check for differences in keywords set, and for new groups to publish
      newTagcache = {}; for _, v in ipairs(allgrps) do if v['tagcache'] and contains('MQTT', v['tagcache']) then newTagcache[v['address']] = v['tagcache'] end end
      unpublished = {}
      n = 1
      for k, v in pairs(newTagcache) do
        modified = false
        if not currTagcache[k] then modified = true
        elseif currTagcache[k] ~= v then modified = true end
        if modified then
          p = string.split(k, '/')
          app = tonumber(p[2])
          group = tonumber(p[3])
          if p[4] ~= nil then channel = tonumber(p[4]) else channel = nil end
          unpublished[n] = {app=app, group=group, channel=channel}
          n = n + 1
        end
      end
      toPublish = n - 1
      published = 0
      if toPublish > 0 then log('Queued '..toPublish..' objects with keyword MQTT for publication') end
      -- Handle deletions
      for k, v in pairs(currTagcache) do
        if not newTagcache[k] then
          tags = string.split(v, ', ')
          for _, t in ipairs(tags) do
            tp = string.split(t, '=')
            if not tp[2] and tp[1] ~= 'MQTT' then dType = tp[1]; break end
          end
          parts = string.split(k, '/')
          net = 254; app = parts[2]; group = parts[3];
          if parts[4] then oid = 'cbus_mqtt_'..net..'_'.. app..'_'..group..'_'..parts[4] else oid = 'cbus_mqtt_'..net..'_'.. app..'_'..group end
          local topic = mqttDiscoveryTopic..'/'..dType..'/'..oid..'/config'
          log('Remove discovery topic '..topic)
          client:publish(topic, '', 1, true)
          local topic = mqttDiscoveryTopic..'/read/254/'..app..'/'..group;
          client:publish(topic..'/state', '', 1, true)
          client:publish(topic..'/level', '', 1, true)
        end
      end
      currTagcache = newTagcache
    else
      allgrps = grp.all()
      currTagcache = {}; for _, v in ipairs(allgrps) do if v['tagcache'] and contains('MQTT', v['tagcache']) then currTagcache[v['address']] = v['tagcache'] end end
    end
  end

  -- Publish any queued additions
  if #unpublished > 0 then
    if notify then
      log('Publishing discovery and current level topics')
      notify = false
    end
    addDiscover(254, unpublished[1].app, unpublished[1].group, unpublished[1].channel)
    if unpublished[1].app ~= 228 then
      publish(254, unpublished[1].app, unpublished[1].group, GetCBusLevel(0, unpublished[1].app, unpublished[1].group))
    else
      publishMeasurement(254, unpublished[1].app, unpublished[1].group, unpublished[1].channel, GetCBusMeasurement(0, unpublished[1].group, unpublished[1].channel))
    end
    table.remove(unpublished, 1)
    published = published + 1
    if #unpublished == 0 then log('Publishing completed for '..published..' discovery and current level topics') end
  end

  --[[
  Send a heartbeat periodically to port 5433. If execution is disrupted by an error then
  this script will be re-started by the 'MQTT lastlevel' resident script
  --]]
  local stat, err = pcall(function ()
    if os.time() - heartbeat >= 10  and status ~= 2 then
      heartbeat = os.time()
      require('socket').udp():sendto('MQTTsend+'..heartbeat, '127.0.0.1', 5433)
    end
  end)
  if not stat then -- If sending the heartbeat faults then exit the loop - the script will re-start
    log('A fault occurred sending heartbeat. Restarting...')
    do return end
  end
end

 

Probably better, here's my blog post on the subject that will be updated if there are further developments. I've added seamless Philips Hue integration with CBus (so I now get a true "All Off" button from a scene - YAY), and improved a bunch of other aspects.

https://www.map59.com/home-assistant-cbus-mqtt-and-philips-hue/

 

Looks like you have had some fun digging into this.

I went through a similar adventure a few years back with this.

https://github.com/ribenajuice/NACSHAC-Lua/tree/main/MQTTHomeAssistant

 

Nice work!

 

Hi @ssaunders, Just want to say Hi and to say thanks a million for posting all that info on your blog, amazing stuff!
You've put a ton of work into that, and have saved me days, if not weeks, of effort!
I got it all going in about 10 mins, and it has been working perfectly for a week now - Kudos for sharing

 

A pleasure, and G'day! You might want to check out the changes I made over the past few days, posted only yesterday as an update to that blog article. +Panasonic AC, +ESPHome sensors, plus a significant performance improvement and a crash fix.

I have 74 MQTT tagged objects, and encounted a crash every evening when I pressed an "all off" button before bed. I think I introduced this bug after my code was posted to the article the last time, so it may not affect you, but the code optimisation I've done is definitely worth checking out as it vastly improves performance for some things. Some functions were taking just under a second to run at my scale, and now execute in around 200ms...

It also consolidates MQTT send and receive as a single script and lowers traffic by avoiding setting topics if they're already at the same value.

https://www.map59.com/home-assistant-cbus-mqtt-and-philips-hue/

 

Thanks to a prod from @Timbo, I've uploaded this code to Github. Blog will still be maintained, and Git can track the changes.

https://github.com/autoSteve/acMqtt

Things are improved @paddyb & @vworp.

 

Many thanks, Steve! I've been following your blog for updates, Github will make it a bit easier to spot the differences between revisions. Really appreciate the continued effort. I've used this method now on a couple of clients installs also and am getting positive results. When you couple this MQTT integration with the relatively new Cloudflared addon in Homeassistant, it provides a fantastic and simple-to-use GUI interface to a C-Bus system, even when the system is installed behind carrier-grade NATs etc. This can only help to aid the longevity of the system as a whole.

 

Hopefully I'm near done with the code at https://github.com/autoSteve/acMqtt for integration of CBus with Home Assistant. It has given, and is still giving me much satisfaction.

Supported now are:

• Light
• Fan
• Cover
• Select - set a CBus level to specific values from HA, which I use for blind pre-sets
• Sensor
• Switch
• Binary_sensor
• Bsensor - a (binary) sensor configurable with custom on/off strings like Motion detected/No motion, or Door open/Door closed
• Button - trigger level set to trigger things like scenes, or pulse the group for lighting app

Implemented are lighting, measurement, user parameter and trigger apps on multiple networks, with discoverability by Home Assistant, and a return to last level set for HA 'on' commands.

Plus bonus Philips Hue integration with CBus, and ESPHome ESP-32 device support in CBus of environment sensors and Panasonic air conditioners.

Availability with last will/status MQTT topics has now also been added, so if the script stops the devices/entities show in HA as unavailable.

I love this code. It's made integrating CBus and Home Assistant using an automation controller ultimately so simple and flexible. Thanks to everyone on the CBus forum for their knowledge, tid-bits, hints and suggestions.

I have licensed it Creative Commons Zero, declaring it public domain. If it's of use, just beer me to say thanks should our paths cross.

Feel free to hit me up at GitHub for further improvements.

 

Hi, I fell in love with your scripts when I ran across this project this weekend. Auto discovery for CBUS in HA is a must and you've helped another soul clean up their HA config... Thankyou!

I was wondering if your sensor config is exposing CBUS sensors for light values or even just occupancy? I've never had them displayed in HA given their config in CBUS system.

 

Bloody great to hear @arrikhan. Glad it's helped.

I currently use 'sensor' types to display things like pool and spa temperature, rainfall stats, and a near-term forecast. The NAC gets forecast from the Weatherzone API (setting user parameters), and rainfall using a rain sensor that pulses an analogue input. I use the local rainfall to vary irrigation timing, displaying it in HA for no reason whatsoever other than interest.

The bsensor/binary sensor types I do not personally use, but developed the code for someone else who wanted a motion sensor state indication in HA.

 

This is simply brilliant - thank you. The instructions are easy to follow and very complete. I now have a couple of switches working 2 ways and some sensors working Cbus to HASS but not vice versa. I am keen to publish my powerwall SOC from HASS to CBus and have created a user variable in CBus and have it visible in MQTT explorer but have failed to publish the sensor value from HASS to MQTT - any hints please?

 

My pleasure.

Some kind of automation in HASS to mirror a powerwall sensor value to a user parameter exposed to HASS via MQTT from a SHAC/NAC?

Or, you could go get the PowerWall SOC directly using a CBus automation controller in LUA?

Auth hints: https://forum.logicmachine.net/showthread.php?tid=3308
API hints: https://github.com/vloschiavo/powerwall2

I don't have a PowerWall, so can't try things out for you, but the API seems straightforward enough. There's a GET call for state of charge.

My HUE code makes REST calls, but auth will be different. There may be some hints in that LUA for you if you want to go the PowerWall API via Automation Controller route. I tried to get HA to do the heavy lifting with Philips Hue integration to provide a bridge to CBus. I failed. The HUE LUA code I wrote is the result, where both HA and my NAC talk to the Hue Bridge. So you could do the same with the PowerWall.

 

sorry - hit the send button before I started!

I have put an automation in HASS to publish the sensor value to MQTT broker. I then added a resident script in SHAC to moniitor that parameter and update SHAC when it changes. it works but seems to be "inelegant" compared to some of the other types of devices. "switches", for instance, appear to work 2 ways natively. Is it a characteristic of sensors that it is only one way (which makes sense after all).

Powerwall drect from SHAC is messy and I have just got it working with HASS (thanks to other good people like you) so will not be taking that route.....

let's hope I can fumble through with the other stuff I need!