completed redis lock release functions

server/src/_luaScriptsV2/deduction/lock/lockReceipt.lua

@@ -0,0 +1,59 @@
+-- ============================================================================
+-- LOCK RECEIPT HELPERS
+-- Helpers for loading, building, and storing lock receipts in RedisJSON
+-- ============================================================================
+
+-- ============================================================================
+-- HELPER: Decode a RedisJSON root value
+-- JSON.GET on '$' returns an array of matches, so unwrap the first element.
+-- ============================================================================
+local function decode_root_json(result)
+  if is_nil(result) then
+    return nil
+  end
+
+  local decoded = cjson.decode(result)
+  if type(decoded) == 'table' and decoded[1] ~= nil then
+    decoded = decoded[1]
+  end
+
+  if type(decoded) ~= 'table' then
+    return nil
+  end
+
+  return decoded
+end
+
+-- ============================================================================
+-- HELPER: Load lock receipt from Redis
+-- Returns the decoded receipt table or nil if the key does not exist.
+-- ============================================================================
+local function load_lock_receipt(lock_receipt_key)
+  local result = redis.call('JSON.GET', lock_receipt_key, '$')
+  return decode_root_json(result)
+end
+
+-- ============================================================================
+-- HELPER: Store lock receipt in Redis
+-- Overwrites the full receipt document at the lock receipt key.
+-- ============================================================================
+local function store_lock_receipt(lock_receipt_key, receipt)
+  redis.call('JSON.SET', lock_receipt_key, '$', cjson.encode(receipt))
+  return receipt
+end
+
+-- ============================================================================
+-- HELPER: Save a lock receipt from deduction update objects
+--
+-- params:
+--   lock_receipt_key: string
+--   receipt: table (base receipt metadata to persist)
+--   mutation_logs: table | nil
+-- ============================================================================
+local function save_lock_receipt_from_updates(params)
+  local receipt = params.receipt or {}
+  local mutation_logs = params.mutation_logs or {}
+  receipt.items = #mutation_logs > 0 and mutation_logs or cjson.decode('[]')
+
+  return store_lock_receipt(params.lock_receipt_key, receipt)
+end