Script to track Day Ahead prices for electricity on the ENTSOE-E Platform

[fleeceable]

Good work @tigi! 

I usually add automatic group address creation on this kind of programs so when you copy code to a new LM, you can run this program within seconds.
Also edited line 151 (group address was hard coded) and removed Average, Min and Max price Group addresses because these gonna generated automatically...
Now you need basically edit only three group address:  StartGrpAddr,  StartGrpAddrPercent and objaddrCheckUpdateTime + activate "create_addresses" on first time when running the code.

I have some ideas to create controlling part (solar inverters and battery charging/discharging) on top of this code but let's see when I have time to do that. Gonna share the results then...
 

Code:

local fetchfortommorow = true -- true for tommorow, false for today
local SecurityTokenAPI = 'your-api-key-in-here' -- your personal security token, get it at entsoe transparency platform
local EntsoeDomain = '10Y1001A1001A39I' -- find your domain for the country you are living at https://transparency.entsoe.eu/content/static_content/Static%20content/web%20api/Guide.html#_load_domain
local StartGrpAddr = '60/1' -- group addresses used to store the €/MWh prices per hour, x/x/0 is 00:00 hour, x/x/1 is 01:00 hour
local StartGrpAddrPercent = '60/2' -- group addresses to store calculated pecentages for the hours, x/x/0 is 00:00 hour
local SecondsPastTillRefetch =  39600 -- seconds that must be past till new refetch will be done, default 39600 seconds, is 11 hours
local StartTimeHours=13 -- start time in which fetching is allowed, used in function IsTimeBetween
local StartTimeMinutes=00 -- start minutes in which fetching is allowed, used in function IsTimeBetween
local StopTimeHours=23 -- stop time in which fetching is allowed, used in function IsTimeBetween
local StopTimeMinutes=59 -- stop minutes in which fetching is allowed, used in function IsTimeBetween
local objaddrCheckUpdateTime = '60/1/0' -- object to check last updated date from
--local objaddrAverageprice = '60/1/25' -- object to store average value
--local objaddrLowestprice = '60/1/26' -- object to store groupaddress of lowest price of the day
--local objaddrHighestprice = '60/1/27' -- object to store groupaddress of highest price of the day
local PrintLOG = false -- logging
local create_addresses = false

--**********CREATE GROUP ADDRESSES******************
function createga(groupaddress,datatype2,name2)
  exist = grp.alias(groupaddress)
  if exist == nil then
    address = grp.create({
    datatype = datatype2,
    address = groupaddress,
    name = name2,
    comment = 'Automatically created object',
    units = '',
    tags = { },
    })
  end
end

if create_addresses then
  for i= 0, 27, 1 do
    if i < 24 then
      createga(StartGrpAddr ..'/'..i,dt.float32,'Electric - Entsoe day ahead  ' .. i)
      createga(StartGrpAddrPercent ..'/'..i,dt.uint16,'Electric - Entsoe day ahead  ' .. i .. ' Percent')
    elseif    i==25 then
      createga(StartGrpAddr ..'/'..i,dt.float32,'Electric - Entsoe day ahead Average')
    elseif i == 26 then
      createga(StartGrpAddr ..'/'..i,dt.string,'Electric - Entsoe day ahead Lowest GrpAddr') 
    elseif i == 27 then
      createga(StartGrpAddr ..'/'..i,dt.string,'Electric - Entsoe day ahead Highest GrpAddr')
    end
  end
  os.sleep(2)
end

  -- https://stackoverflow.com/questions/35402992/how-to-check-if-current-time-is-between-two-others
  -- Function to check if current time is between 2 other defined times
  -- Returns true if time is between 2 other times
  local function getMinutes(hours, minutes)
      return (hours*60)+minutes
  end

  local function IsTimeBetween(StartH, StartM, StopH, StopM, TestH, TestM)
      if (StopH < StartH) then -- add 24 hours if endhours < starthours
          local StopHOrg=StopH
          StopH = StopH + 24
          if (TestH <= StopHOrg) then -- if endhours has increased the currenthour should also increase
              TestH = TestH + 24
          end
      end

      local StartTVal = getMinutes(StartH, StartM)
      local StopTVal = getMinutes(StopH, StopM)
      local curTVal = getMinutes(TestH, TestM)
      return (curTVal >= StartTVal and curTVal <= StopTVal)
  end   

  local function IsNowBetween(StartH,StartM,StopH,StopM)
    local time = os.date("*t")
      if PrintLOG then
    log(time.hour, time.min) --check if time is correct, if not change to os.date("!*t") for UTC time
    end
    return IsTimeBetween(StartH, StartM, StopH, StopM, time.hour, time.min)
  end
    if PrintLOG then
      log(IsNowBetween(StartTimeHours, StartTimeMinutes, StopTimeHours, StopTimeMinutes))
  end
  -- https://stackoverflow.com/questions/35402992/how-to-check-if-current-time-is-between-two-others

objectupdatedate = (grp.find(objaddrCheckUpdateTime).updatetime) -- get update date for chosen object
diff = os.difftime(os.time(),objectupdatedate) -- difference between current time and objectupdatetime in seconds
if diff > SecondsPastTillRefetch then --check if last run was more than x seconds ago https://www.google.com/search?q=seconds+to+hours
      if PrintLOG then
          log('more than '..SecondsPastTillRefetch..' seconds since last run')
    end
    if (IsNowBetween(StartTimeHours, StartTimeMinutes, StopTimeHours, StopTimeMinutes)) then --check if current time is between hours that data can be fetched
        if PrintLOG then   
            log('data can be fetched')
      end
     
      -- https://forum.logicmachine.net/showthread.php?tid=4268&highlight=entsoe
      if fetchfortommorow then
        date = os.date('%Y%m%d', os.time() + 86400) -- date is tommorow, default setting
      else
        date = os.date('%Y%m%d') --date is today
      end

      periodstart = date .. '0000'
      periodend = date .. '2300'
      log(date)

      url = 'https://web-api.tp.entsoe.eu/api?securityToken='..SecurityTokenAPI..'&' ..
        'documentType=A44&in_Domain='..EntsoeDomain..'&out_Domain='..EntsoeDomain..
        '&periodStart=' .. periodstart .. '&periodEnd=' .. periodend

      data, code = require('socket.http').request(url)
      if not data or code ~= 200 then
        log('request failed', data, code)
        return
      end

      prices = {}
      key = 0

      callbacks = {
        StartElement = function(p, tag)
          if tag == 'TimeSeries' then
            key = key + 1
            prices[ key ] = {}
          elseif tag == 'position' then
            state = 'position'
          elseif tag == 'price.amount' then
            state = 'price'
          end
        end,
        EndElement = function(p, tag)
          state = nil
        end,
        CharacterData = function(p, value)
          value = value:trim()

          if #value > 0 then
            if state == 'position' then
              position = tonumber(value)
            elseif state == 'price' then
              prices[ key ][ position ] = tonumber(value)
            end
          end
        end
      }

      parser = require('lxp').new(callbacks)
      parser:parse(data)
      parser:close()

      if key > 0 then
        for i, price in pairs(prices[ 1 ]) do
          j = i - 1 -- shifts the first key from 1 to 0, so the first groupaddress is x/x/0 for 00:00 hour, next is x/x/1 for 01:00 hour,etc...
            grp.checkupdate(StartGrpAddr..'/' .. j, price) -- update objects with newest prices
          --log('uur ' ..j..' prijs: ' ..price)
        end
            
          -- https://stackoverflow.com/questions/69359710/how-to-get-the-smallest-number-in-a-table-with-lua
               lowestprice = math.min(unpack(prices[ 1 ])) --lowest number in table
                 highestprice = math.max(unpack(prices[ 1 ])) --highest number in table
     
            -- https://stackoverflow.com/questions/25835591/how-to-calculate-percentage-between-the-range-of-two-values-a-third-value-is
                --input = grp.getvalue('34/1/13')
          for i, price in pairs(prices[ 1 ]) do
         j = i - 1
             percentage = ((price - lowestprice) * 100) / (highestprice - lowestprice)
             --log('at hour '..j..':00 price is '..math.floor(percentage)..'% higher than lowest price today')
        grp.checkupdate(StartGrpAddrPercent..'/' .. j, percentage) --update objects with newest percentages
       
          if lowestprice == price then
              grp.checkupdate(StartGrpAddr .. '/26', StartGrpAddr..'/' .. j)
          end
          if highestprice == price then
              grp.checkupdate(StartGrpAddr .. '/27', StartGrpAddr..'/' .. j)
          end
        end
     
          -- https://www.codegrepper.com/code-examples/lua/lua+calculate+average+number
          function math.average(t)
            local sum = 0
                for _,v in pairs(t) do -- Get the sum of all numbers in t
              sum = sum + v
            end
            return sum / #t
          end
        grp.checkupdate(StartGrpAddr .. '/25', math.average((prices[ 1 ])))
        end
     -- https://forum.logicmachine.net/showthread.php?tid=4268&highlight=entsoe
     else
        if PrintLOG then
            log('data cannot be fetched yet')
      end
      end 
else
  if PrintLOG then
      log('data has already been fetched and updated, not necessary to re-fetch data')
  end
end