[mod] redislib - optimize LUA script registration.

Instead of register the LUA script on each call, the LUA script is registered
once and the `Script` object is cached in global storage.

[1] https://github.com/searxng/searxng/pull/1047#discussion_r884143305

Signed-off-by: Markus Heiser <markus.heiser@darmarit.de>
This commit is contained in:
Markus Heiser 2022-05-30 11:05:24 +02:00
parent 4b185f0e11
commit 1a8ff10e30
1 changed files with 31 additions and 3 deletions

View File

@ -14,6 +14,34 @@ import hmac
from searx import get_setting
LUA_SCRIPT_STORAGE = {}
"""A global dictionary to cache client's ``Script`` objects, used by
:py:obj:`lua_script_storage`"""
def lua_script_storage(client, script):
"""Returns a redis :py:obj:`Script
<redis.commands.core.CoreCommands.register_script>` instance.
Due to performance reason the ``Script`` object is instantiated only once
for a client (``client.register_script(..)``) and is cached in
:py:obj:`LUA_SCRIPT_STORAGE`.
"""
# redis connection can be closed, lets use the id() of the redis connector
# as key in the script-storage:
client_id = id(client)
if LUA_SCRIPT_STORAGE.get(client_id) is None:
LUA_SCRIPT_STORAGE[client_id] = {}
if LUA_SCRIPT_STORAGE[client_id].get(script) is None:
LUA_SCRIPT_STORAGE[client_id][script] = client.register_script(script)
return LUA_SCRIPT_STORAGE[client_id][script]
PURGE_BY_PREFIX = """
local prefix = tostring(ARGV[1])
for i, name in ipairs(redis.call('KEYS', prefix .. '*')) do
@ -41,7 +69,7 @@ def purge_by_prefix(client, prefix: str = "SearXNG_"):
.. _DEL: https://redis.io/commands/del/
"""
script = client.register_script(PURGE_BY_PREFIX)
script = lua_script_storage(client, PURGE_BY_PREFIX)
script(args=[prefix])
@ -123,7 +151,7 @@ def incr_counter(client, name: str, limit: int = 0, expire: int = 0):
(5, 1)
"""
script = client.register_script(INCR_COUNTER)
script = lua_script_storage(client, INCR_COUNTER)
name = "SearXNG_counter_" + secret_hash(name)
c = script(args=[limit, expire], keys=[name])
return c
@ -207,7 +235,7 @@ def incr_sliding_window(client, name: str, duration: int):
1
"""
script = client.register_script(INCR_SLIDING_WINDOW)
script = lua_script_storage(client, INCR_SLIDING_WINDOW)
name = "SearXNG_counter_" + secret_hash(name)
c = script(args=[duration], keys=[name])
return c