python - Scrapy 不下载图像并出现管道错误

Question

我有这个代码

class MyImagesPipeline(ImagesPipeline):
    def get_media_requests(self, item, info):
            for image_url in item['image_urls']:
                yield Request(image_url)

这是 BaseSpider 的子类蜘蛛。这只蜘蛛给我带来了噩梦

def parse(self, response):

    hxs = HtmlXPathSelector(response)
    sites = hxs.select('//strong[@class="genmed"]')
    items = []


    for site in sites[:5]:

        item = PanduItem()
        item['username'] = site.select('dl/dd/h2/a').select("string()").extract()
        item['number_posts'] = site.select('dl/dd/h2/em').select("string()").extract()
        item['profile_link'] = site.select('a/@href').extract()



        request =  Request("http://www.example/profile.php?mode=viewprofile&u=5",
        callback = self.parseUserProfile)
        request.meta['item'] = item
        return request

---

 def parseUserProfile(self, response):

        hxs = HtmlXPathSelector(response)
        sites = hxs.select('//div[@id="current')
        myurl = sites[0].select('img/@src').extract()

        item = response.meta['item']

        image_absolute_url = urljoin(response.url, myurl[0].strip())
        item['image_urls'] = [image_absolute_url]

        return item

---

这是我收到的错误。我找不到。看起来像是正在获取元素，但我不确定

ERROR

File "/app_crawler/crawler/pipelines.py", line 9, in get_media_requests
            for image_url in item['image_urls']:
        exceptions.TypeError: 'NoneType' object has no attribute '__getitem__'

Answer 1

您的 pipelines.py 中缺少一个方法 该文件包含3个方法:

• 处理项目
• 获取媒体请求
• item_completed

item_completed 方法负责将图像保存到指定路径。该路径在settings.py中设置如下:

ITEM_PIPELINES = ['scrapy.contrib.pipeline.images.ImagesPipeline']
IMAGES_STORE = '/your/path/here'

如上所示，settings.py 中还包含启用 imagepipeline 的行。

我尝试以我能理解的最好方式来解释它。如需进一步引用，请查看官方scrapy documentation .