in scripts/lua/lib/redis.lua [420:428]
function _M.addResourceToIndex(red, index, resourceKey, snapshotId)
if snapshotId ~= nil then
index = utils.concatStrings({'snapshots:', snapshotId, ':', index})
end
local ok, err = sadd(red, index, resourceKey)
if not ok then
request.err(500, utils.concatStrings({"Failed to update the resource index set: ", err}))
end
end