环境

Python：2.7.6(64位)
Scrapy：0.22.2(64位)
操作系统：Windows7(64位)

问题需求

默认情况下，使用ImagePipeline组件下载图片的时候，图片名称是以图片URL的SHA1值进行保存的。
如：
图片URL:http://www.example.com/image.jpg
SHA1结果：3afec3b4765f8f0a07b78f98c07b83f013567a0a
则图片名称：3afec3b4765f8f0a07b78f98c07b83f013567a0a.jpg
但是，我想要以原来的图片名称进行保存，比如上面例子中的图片保存到本地的话，图片名称就应该是：image.jpg
stackoverflow上说是可以重写image_key函数，不过我试了下，结果发现不行，重写的image_key函数没被调用。后面查看了下ImagePipeline的源码：

class ImagesPipeline(FilesPipeline): """Abstract pipeline that implement the image thumbnail generation logic """ MEDIA_NAME = 'image' MIN_WIDTH = 0 MIN_HEIGHT = 0 THUMBS = {} DEFAULT_IMAGES_URLS_FIELD = 'image_urls' DEFAULT_IMAGES_RESULT_FIELD = 'images' ...省略 def file_path(self, request, response=None, info=None): ## start of deprecation warning block (can be removed in the future) def _warn(): from scrapy.exceptions import ScrapyDeprecationWarning import warnings warnings.warn('ImagesPipeline.image_key(url) and file_key(url) methods are deprecated, ' 'please use file_path(request, response=None, info=None) instead', category=ScrapyDeprecationWarning, stacklevel=1) # check if called from image_key or file_key with url as first argument if not isinstance(request, Request): _warn() url = request else: url = request.url # detect if file_key() or image_key() methods have been overridden if not hasattr(self.file_key, '_base'): _warn() return self.file_key(url) elif not hasattr(self.image_key, '_base'): _warn() return self.image_key(url) ## end of deprecation warning block image_guid = hashlib.sha1(url).hexdigest() # change to request.url after deprecation return 'full/%s.jpg' % (image_guid) # deprecated def image_key(self, url): return self.file_path(url) image_key._base = True ...省略

其中，有这么一句话：
ImagesPipeline.image_key(url) and file_key(url) methods are deprecated, please use file_path(request, response=None, info=None) instead
也就是说，在最新版本的Scrapy中（0.22.2），使用file_path代替image_key函数。
因此，我在自定义的ImagePipeline类中，重写了file_path函数，但是结果运行的时候，发现也没法被调用。
代码如下：

from scrapy.contrib.pipeline.images import ImagesPipeline from scrapy.exceptions import DropItem from scrapy.http import Request import os class DownPhotosPipeline(ImagesPipeline): def file_path(self, request): print "~~~~~~~~~~~~~~~~~~~~~~" print "~~~~~~~"+request.url+"~~~~~~~" print "~~~~~~~~~~~~~~~~~~~~~~" image_guid = request.url.split('/')[-1] return 'full/%s' % (image_guid) def get_media_requests(self, item, info): for image_url in item['images']: yield Request(image_url) def item_completed(self, results, item, info): image_paths = [x['path'] for ok, x in results if ok] if not image_paths: raise DropItem("Item contains no images") #item['image_paths'] = image_paths return item

settings.py

DOWNLOAD_DELAY = 2 IMAGES_STORE = 'budejie_photos' DOWNLOAD_TIMEOUT = 1200 ITEM_PIPELINES = ['scrapy.contrib.pipeline.images.ImagesPipeline' ]