Shelly - WiFi IoT-Devices

[a455115]

Code:

if not broker then   broker = '127.0.0.1'   function multiply(mult)     return function(value)       local num = tonumber(value)       if num then         return num * mult       else         return value       end     end   end   -- topic to object map   mqtt_to_object = {     ['shellies/shellyplug-s-D9AA39/relay/0'] = '32/1/1',     ['shellies/shellyplug-s-D9AA39/temperature'] = '32/1/2',   } -- optional topic value conversion function mqtt_to_object_conv = {   ['shellies/shellyplug-s-D9AA39/relay/0'] = multiply(1),    ['shellies/shellyplug-s-D9AA39/temperature'] = multiply(1), }   -- object to topic map object_to_mqtt = {    -- ['1/1/1'] = 'out/topic1',    -- ['1/1/2'] = 'out/topic2',   }   datatypes = {}   grp.sender = 'mq'   require('socket')   for addr, _ in pairs(object_to_mqtt) do     local obj = grp.find(addr)     if obj then       datatypes[ addr ] = obj.datatype     end   end   mclient = require('mosquitto').new()   mclient.ON_CONNECT = function(res, ...)     log('mqtt connect status', res, ...)     if res then       for topic, _ in pairs(mqtt_to_object) do         mclient:subscribe(topic)       end     else       mclient:disconnect()     end   end   mclient.ON_MESSAGE = function(mid, topic, payload)     local addr = mqtt_to_object[ topic ]     if addr then       local fn = mqtt_to_object_conv[ topic ]       if fn then         payload = fn(payload)       end       grp.write(addr, payload)     end   end   mclient.ON_DISCONNECT = function(...)     log('mqtt disconnect', ...)     mclientfd = nil   end   function mconnect()     local fd     mclient:connect(broker)     fd = mclient:socket()     -- fd ref is valid     if fd then       mclientfd = fd     end   end   mconnect()   function publishvalue(event)     -- message from us or client is not connected     if event.sender == 'mq' or not mclientfd then       return     end     local addr = event.dst     local dpt = datatypes[ addr ]     local topic = object_to_mqtt[ addr ]     -- unknown object     if not dpt or not topic then       return     end     local value = busdatatype.decode(event.datahex, dpt)     if value ~= nil then       if type(value) == 'boolean' then         value = value and 1 or 0       end       mclient:publish(topic, tostring(value))     end   end   lbclient = require('localbus').new(1)   lbclient:sethandler('groupwrite', publishvalue)   lbclientfd = socket.fdmaskset(lbclient:getfd(), 'r')   -- run timer every 5 seconds   timer = require('timerfd').new(5)   timerfd = socket.fdmaskset(timer:getfd(), 'r') end -- mqtt connected if mclientfd then   mclientfdset = socket.fdmaskset(mclientfd, mclient:want_write() and 'rw' or 'r')   res, lbclientstat, timerstat, mclientstat =       socket.selectfds(10, lbclientfd, timerfd, mclientfdset) -- mqtt not connected else   res, lbclientstat, timerstat =     socket.selectfds(10, lbclientfd, timerfd) end if mclientfd and mclientstat then   if socket.fdmaskread(mclientstat) then     mclient:loop_read()   end   if socket.fdmaskwrite(mclientstat) then     mclient:loop_write()   end end if lbclientstat then   lbclient:step() end if timerstat then   -- clear armed timer   timer:read()   if mclientfd then     mclient:loop_misc()   else     mconnect()   end end

Hi admin,
How do I convert directly from the code to get a specific parameter from the Json it returns? For an example of a specific topic it returns json to me 

shellies/shellytrv-14B457E5C2C8/info
return
{"tmp": {"value":24.5,"units": "C","is_valid": true},"target_t":{"enabled":false,"value":22.0,"units":"C "},"temperature_offset":0.0,"bat":99}

I only want to extract from it:
target_t - value - 1/1/1
bat - 1/1/2
How can I extract only this with the above code?