python爬虫scrapy框架遇到一个bug，求解决！！

[Heng360]

目标：爬取豆瓣TOP250电影名字，简介：

movies.py:

import scrapy
from douban.items import DoubanItem

class MoviesSpider(scrapy.Spider):
    name = "movies"
    allowed_domains = ["movie.douban.com"]
    start_urls = ["https://movie.douban.com/top250"]

    def parse(self, response):
        item = DoubanItem()
        print(response.headers["user_agent"])

        li_list = response.xpath("//ol[@class='grid_view']/li")

        for li in li_list:
            item["name"] = li.xpath(".//div[@class='hd']/a/span[1]/text()")[0].extract_first()
            item["score"] = li.xpath(".//div[@class='star']/span[2]/text()")[0].extract_first()
            item["desc"] = li.xpath(".//p[@class='quote']/span/text()")[0].extract_first()
            item["src"] = li.xpath(".//div[@class='pic']/a/img/@src")[0].extract_first()
            yield item
        url = response.xpath("//span[@class='next']/a/@href")[0].extract_first()
        if url is not None:
            url = response.urljoin(url)
            yield scrapy.Request(url=url,callback=self.parse)

middlewares.py:

def process_request(self, request, spider):
    # Called for each request that goes through the downloader
    # middleware.

    # Must either:
    # - return None: continue processing this request
    # - or return a Response object
    # - or return a Request object
    # - or raise IgnoreRequest: process_exception() methods of
    #   installed downloader middleware will be called
    referer = request.referer
    if referer:
        request.headers["referer"] = referer
    ua = random.choice(USER_AGENT_LIST)
    request.headers["user_agent"] = ua
    return None
pipelines.py:

class JsonPipeline:
    def __init__(self):
        self.file = open("top250.json","wb")
    def process_item(self, item, spider):
        # 强行转化为字典类型
        item = dict(item)
        # 将数据序列化
        data = json.dumps(item,ensure_ascii=False) + ",\n"
        self.file.write(data.encode("utf-8"))
        self.file.close()



        return item

Terminal:

2024-02-04 01:53:09 [scrapy.utils.log] INFO: Versions: lxml 5.1.0.0, libxml2 2.10.3, cssselect 1.2.0, parsel 1.8.1, w3lib 2.1.2, Twisted 22.10.0, Python 3.9.6 (tags/v3.9.6:db3ff76, Jun 28 2021, 15:26:21) [MSC v.1929 64 bit (AMD64)], pyOpenSSL 24.0.0 (OpenSSL 3.2.0 23 Nov 2023), cryptography 42.0.1, Platform Windows-10-10.0.22621-SP0
2024-02-04 01:53:09 [scrapy.addons] INFO: Enabled addons:
[]
2024-02-04 01:53:09 [asyncio] DEBUG: Using selector: SelectSelector
2024-02-04 01:53:09 [scrapy.utils.log] DEBUG: Using reactor: twisted.internet.asyncioreactor.AsyncioSelectorReactor
2024-02-04 01:53:09 [scrapy.utils.log] DEBUG: Using asyncio event loop: asyncio.windows_events._WindowsSelectorEventLoop
2024-02-04 01:53:09 [scrapy.extensions.telnet] INFO: Telnet Password: 6c6a92b61900eb9a
2024-02-04 01:53:09 [scrapy.middleware] INFO: Enabled extensions:
['scrapy.extensions.corestats.CoreStats',
 'scrapy.extensions.telnet.TelnetConsole',
 'scrapy.extensions.logstats.LogStats']
2024-02-04 01:53:09 [scrapy.crawler] INFO: Overridden settings:
{'BOT_NAME': 'douban',
 'FEED_EXPORT_ENCODING': 'utf-8',
 'NEWSPIDER_MODULE': 'douban.spiders',
 'REQUEST_FINGERPRINTER_IMPLEMENTATION': '2.7',
 'SPIDER_MODULES': ['douban.spiders'],
 'TWISTED_REACTOR': 'twisted.internet.asyncioreactor.AsyncioSelectorReactor'}
2024-02-04 01:53:11 [scrapy.middleware] INFO: Enabled downloader middlewares:
['scrapy.downloadermiddlewares.httpauth.HttpAuthMiddleware',
 'scrapy.downloadermiddlewares.downloadtimeout.DownloadTimeoutMiddleware',
 'scrapy.downloadermiddlewares.defaultheaders.DefaultHeadersMiddleware',
 'scrapy.downloadermiddlewares.useragent.UserAgentMiddleware',
 'douban.middlewares.DoubanDownloaderMiddleware',
 'scrapy.downloadermiddlewares.retry.RetryMiddleware',
 'scrapy.downloadermiddlewares.redirect.MetaRefreshMiddleware',
 'scrapy.downloadermiddlewares.httpcompression.HttpCompressionMiddleware',
 'scrapy.downloadermiddlewares.redirect.RedirectMiddleware',
 'scrapy.downloadermiddlewares.cookies.CookiesMiddleware',
 'scrapy.downloadermiddlewares.httpproxy.HttpProxyMiddleware',
 'scrapy.downloadermiddlewares.stats.DownloaderStats']
2024-02-04 01:53:11 [scrapy.middleware] INFO: Enabled spider middlewares:
['scrapy.spidermiddlewares.httperror.HttpErrorMiddleware',
 'scrapy.spidermiddlewares.offsite.OffsiteMiddleware',
 'scrapy.spidermiddlewares.referer.RefererMiddleware',
 'scrapy.spidermiddlewares.urllength.UrlLengthMiddleware',
 'scrapy.spidermiddlewares.depth.DepthMiddleware']
2024-02-04 01:53:11 [scrapy.middleware] INFO: Enabled item pipelines:
['douban.pipelines.JsonPipeline']
2024-02-04 01:53:11 [scrapy.core.engine] INFO: Spider opened
2024-02-04 01:53:11 [scrapy.extensions.logstats] INFO: Crawled 0 pages (at 0 pages/min), scraped 0 items (at 0 items/min)
2024-02-04 01:53:11 [movies] INFO: Spider opened: movies
2024-02-04 01:53:11 [scrapy.extensions.telnet] INFO: Telnet console listening on 127.0.0.1:6023
2024-02-04 01:53:11 [scrapy.core.scraper] ERROR: Error downloading <GET https://movie.douban.com/top250>
Traceback (most recent call last):
  File "F:\pythonProject\pythonProject\venv\lib\site-packages\twisted\internet\defer.py", line 1697, in _inlineCallbacks
    result = context.run(gen.send, result)
  File "F:\pythonProject\pythonProject\venv\lib\site-packages\scrapy\core\downloader\middleware.py", line 43, in process_request
    method(request=request, spider=spider)
  File "F:\pythonProject\pythonProject\douban\douban\middlewares.py", line 83, in process_request
    referer = request.referer
AttributeError: 'Request' object has no attribute 'referer'
2024-02-04 01:53:11 [scrapy.core.engine] INFO: Closing spider (finished)
2024-02-04 01:53:11 [scrapy.statscollectors] INFO: Dumping Scrapy stats:
{'downloader/exception_count': 1,
 'downloader/exception_type_count/builtins.AttributeError': 1,
 'elapsed_time_seconds': 0.244997,
 'finish_reason': 'finished',
 'finish_time': datetime.datetime(2024, 2, 3, 17, 53, 11, 599786, tzinfo=datetime.timezone.utc),
 'log_count/DEBUG': 3,
 'log_count/ERROR': 1,
 'log_count/INFO': 11,
 'scheduler/dequeued': 1,
 'scheduler/dequeued/memory': 1,
 'scheduler/enqueued': 1,
 'scheduler/enqueued/memory': 1,
 'start_time': datetime.datetime(2024, 2, 3, 17, 53, 11, 354789, tzinfo=datetime.timezone.utc)}
2024-02-04 01:53:11 [scrapy.core.engine] INFO: Spider closed (finished)
 

 

这个bug怎么解决呢？