Logging & Monitoring KNX activity

[admin]

Some issues with your code:
1. Don't use var1 and similiar variable names. It makes the code hard to read and understand.
2. You should not use storage.all() as it's quite an expensive operation when there is a lot of data in the storage.
3. Your MySQL query does not properly escape input variables. For example, query will fail if object name contains double quotes.

For your task you can use list data type of the storage engine. It allows to create a queue system with multiple scripts adding data to queue and one script reading and removing data from it.

Add item to list:

Code:

list_name = 'log_1'
data = '1234'
storage.exec('rpush', list_name, data)

Get last element of the list (or nil when list is empty):

Code:

function get_last_list_item(key)
  local items = storage.exec('lrange', key, -1, -1)
  if type(items) == 'table' then
    return items[ 1 ]
  end
end

list_name = 'log_1'
last = get_last_list_item(list_name)

Read all entries from multiple lists and remove this data. This code read all storage lists which name starts with "log_".

Code:

-- open single connection for better performance when multiple storage commands are used
storage.openconn()

-- find all matching keys
keys = storage.keys('log_*')

for _, key in ipairs(keys) do
  -- get all elements from the list
  data = storage.exec('lrange', key, 0, -1)

  if type(data) == 'table' then
    for _, item in ipairs(data) do
      -- do something with data
    end

    -- remove read entries from the list
    storage.exec('ltrim', key, #data, -1)
  end
end

storage.closeconn()