rspamd/src/rspamadm/stat_convert.lua

local sqlite3 = require "rspamd_sqlite3"
local redis = require "rspamd_redis"
local _ = require "fun"

local function send_redis(server, symbol, tokens)
  local ret = true
  local conn = redis.connect_sync({
    host = server,
  })

  if not conn then
    print('Cannot connect to ' .. server)
    return false
  end

  _.each(function(t)
    if not conn:add_cmd('HINCRBY', {symbol .. t[3], t[1], t[2]}) then
      ret = false
    end
  end, tokens)
  
  if ret then
    ret = conn:exec()
  end

  return ret
end

return function (args, res)
  local db = sqlite3.open(res['source_db'])
  local tokens = {}
  local num = 0
  local total = 0
  local nusers = 0
  local lim = 1000 -- Update each 1000 tokens
  local users_map = {}
  local learns = {}

  if not db then
    print('Cannot open source db: ' .. res['source_db'])
    return
  end

  db:sql('BEGIN;')
  -- Fill users mapping
  for row in db:rows('SELECT * FROM users;') do
    if row.id == '0' then
      users_map[row.id] = ''
    else
      users_map[row.id] = row.name
    end
    learns[row.id] = row.learned
    nusers = nusers + 1
  end
  -- Fill tokens, sending data to redis each `lim` records
  for row in db:rows('SELECT token,value,user FROM tokens;') do
    local user = ''
    if row.user ~= 0 and users_map[row.user] then
      user = users_map[row.user]
    end
    
    table.insert(tokens, {row.token, row.value, user})
    
    num = num + 1
    total = total + 1
    if num > lim then
      if not send_redis(res['redis_host'], res['symbol'], tokens, users_map) then
        print('Cannot send tokens to the redis server')
        return
      end
      
      num = 0
      tokens = {}
    end
  end
  if #tokens > 0 and 
    not send_redis(res['redis_host'], res['symbol'], tokens, users_map) then
    
    print('Cannot send tokens to the redis server')
    return
  end
  -- Now update all users
  _.each(function(id, learned)
    local user = users_map[id]
    if not redis.make_request_sync({
        host = server,
        cmd = 'HSET',
        args = {symbol .. user, 'learns', learned}
      }) then
      print('Cannot update learns for user: ' .. user)
    end
  end, learns)
  db:sql('COMMIT;')
  
  print(string.format('Migrated %d tokens for %d users for symbol %s',
    total, nusers, res['symbol']))
end