# Source code for scrapy.downloadermiddlewares.stats

    from scrapy.exceptions import NotConfigured
    from scrapy.utils.request import request_httprepr
    from scrapy.utils.response import response_httprepr
    from scrapy.utils.python import global_object_name

    class DownloaderStats:

        def __init__(self, stats):
            self.stats = stats

        @classmethod
        def from_crawler(cls, crawler):
            if not crawler.settings.getbool('DOWNLOADER_STATS'):
                raise NotConfigured
            return cls(crawler.stats)

        def process_request(self, request, spider):
            self.stats.inc_value('downloader/request_count', spider=spider)
            self.stats.inc_value(f'downloader/request_method_count/{request.method}', spider=spider)
            reqlen = len(request_httprepr(request))
            self.stats.inc_value('downloader/request_bytes', reqlen, spider=spider)

        def process_response(self, request, response, spider):
            self.stats.inc_value('downloader/response_count', spider=spider)
            self.stats.inc_value(f'downloader/response_status_count/{response.status}', spider=spider)
            reslen = len(response_httprepr(response))
            self.stats.inc_value('downloader/response_bytes', reslen, spider=spider)
            return response

        def process_exception(self, request, exception, spider):
            ex_class = global_object_name(exception.__class__)
            self.stats.inc_value('downloader/exception_count', spider=spider)
            self.stats.inc_value(f'downloader/exception_type_count/{ex_class}', spider=spider)