scrapy 爬虫 报错如下

2019-01-04 17:55:52 [csrc][scrapy.core.downloader.handlers.http11] WARNING: Got data loss in http://www.csrc.gov.cn/pub/zjhpublic/G00306202/201810/P020181012566963570242.pdf. If you want to process broken responses set the setting DOWNLOAD_FAIL_ON_DATALOSS = False -- This message won't be shown in further requests
2019-01-04 17:55:52 [csrc][scrapy.downloadermiddlewares.retry] DEBUG: Retrying <GET http://www.csrc.gov.cn/pub/zjhpublic/G00306202/201810/P020181012566963570242.pdf> (failed 1 times): [<twisted.python.failure.Failure twisted.internet.error.ConnectionDone: Connection was closed cleanly.>, <twisted.python.failure.Failure twisted.web.http._DataLoss: >]


寻原因