# Source code for scrapy.spidermiddlewares.httperror

    """
    HttpError Spider Middleware

    See documentation in docs/topics/spider-middleware.rst
    """
    import logging

    from scrapy.exceptions import IgnoreRequest

    logger = logging.getLogger(__name__)

    class HttpError(IgnoreRequest):
        """A non-200 response was filtered"""

        def __init__(self, response, *args, **kwargs):
            self.response = response
            super().__init__(*args, **kwargs)

    class HttpErrorMiddleware:

        @classmethod
        def from_crawler(cls, crawler):
            return cls(crawler.settings)

        def __init__(self, settings):
            self.handle_httpstatus_all = settings.getbool('HTTPERROR_ALLOW_ALL')
            self.handle_httpstatus_list = settings.getlist('HTTPERROR_ALLOWED_CODES')

        def process_spider_input(self, response, spider):
            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, exception, spider):
            if isinstance(exception, HttpError):
                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 []