"""
MemoryDebugger extension
See documentation in docs/topics/extensions.rst
"""
from __future__ import annotations
import gc
from typing import TYPE_CHECKING
from scrapy import Spider, signals
from scrapy.crawler import Crawler
from scrapy.exceptions import NotConfigured
from scrapy.statscollectors import StatsCollector
from scrapy.utils.trackref import live_refs
if TYPE_CHECKING:
# typing.Self requires Python 3.11
from typing_extensions import Self
[docs]class MemoryDebugger:
def __init__(self, stats: StatsCollector):
self.stats: StatsCollector = stats
@classmethod
def from_crawler(cls, crawler: Crawler) -> Self:
if not crawler.settings.getbool("MEMDEBUG_ENABLED"):
raise NotConfigured
assert crawler.stats
o = cls(crawler.stats)
crawler.signals.connect(o.spider_closed, signal=signals.spider_closed)
return o
def spider_closed(self, spider: Spider, reason: str) -> None:
gc.collect()
self.stats.set_value(
"memdebug/gc_garbage_count", len(gc.garbage), spider=spider
)
for cls, wdict in live_refs.items():
if not wdict:
continue
self.stats.set_value(
f"memdebug/live_refs/{cls.__name__}", len(wdict), spider=spider
)