"""
HttpError Spider Middleware
See documentation in docs/topics/spider-middleware.rst
"""
from __future__ import annotations
import logging
from typing import TYPE_CHECKING, Any, Iterable, List, Optional
from scrapy import Spider
from scrapy.crawler import Crawler
from scrapy.exceptions import IgnoreRequest
from scrapy.http import Response
from scrapy.settings import BaseSettings
if TYPE_CHECKING:
# typing.Self requires Python 3.11
from typing_extensions import Self
logger = logging.getLogger(__name__)
class HttpError(IgnoreRequest):
"""A non-200 response was filtered"""
def __init__(self, response: Response, *args: Any, **kwargs: Any):
self.response = response
super().__init__(*args, **kwargs)
[docs]class HttpErrorMiddleware:
@classmethod
def from_crawler(cls, crawler: Crawler) -> Self:
return cls(crawler.settings)
def __init__(self, settings: BaseSettings):
self.handle_httpstatus_all: bool = settings.getbool("HTTPERROR_ALLOW_ALL")
self.handle_httpstatus_list: List[int] = settings.getlist(
"HTTPERROR_ALLOWED_CODES"
)
def process_spider_input(self, response: Response, spider: Spider) -> None:
if 200 <= response.status < 300: # common case
return
meta = response.meta
if meta.get("handle_httpstatus_all", False):
return
if "handle_httpstatus_list" in meta:
allowed_statuses = meta["handle_httpstatus_list"]
elif self.handle_httpstatus_all:
return
else:
allowed_statuses = getattr(
spider, "handle_httpstatus_list", self.handle_httpstatus_list
)
if response.status in allowed_statuses:
return
raise HttpError(response, "Ignoring non-200 response")
def process_spider_exception(
self, response: Response, exception: Exception, spider: Spider
) -> Optional[Iterable[Any]]:
if isinstance(exception, HttpError):
assert spider.crawler.stats
spider.crawler.stats.inc_value("httperror/response_ignored_count")
spider.crawler.stats.inc_value(
f"httperror/response_ignored_status_count/{response.status}"
)
logger.info(
"Ignoring response %(response)r: HTTP status code is not handled or not allowed",
{"response": response},
extra={"spider": spider},
)
return []
return None