smart-tiering.lua

-- Lua script to auto-tier S3 object PUT requests
-- based on this: https://ceph.io/en/news/blog/2024/auto-tiering-ceph-object-storage-part-2/

-- exit script quickly if it is not a PUT request
if Request == nil or Request.RGWOp ~= "put_obj" then
  return
end

local threshold = 1024*1024 -- 1MB
local debug = true

-- apply StorageClass only if user hasn't already assigned a storage-class
if Request.HTTP.StorageClass == nil or Request.HTTP.StorageClass == '' then
  if Request.ContentLength < threshold then
    Request.HTTP.StorageClass = "SMALL_OBJ"
  else
    Request.HTTP.StorageClass = "STANDARD"
  end
  if debug then
    RGWDebugLog("applied '" .. Request.HTTP.StorageClass .. "' to object '" .. Request.Object.Name .. "'")
  end
end