使用项目字段中的内容重命名Scrapy 0.24中下载的图像，同时避免文件名冲突？

我正在尝试重命名由Scrapy 0.24 Spider下载的图像。现在，下载的图像以其URL的SHA1哈希作为文件名存储。我想用它们提取的值来命名它们item['model']。2011年的问题概述了我想要的内容，但答案仅适用于Scrapy的早期版本，不适用于最新版本。

一旦设法完成此工作，我还需要确保我考虑到使用相同文件名下载的不同图像。因此，我需要将每个图像下载到它自己的唯一命名的文件夹中，大概是基于原始URL。

这是我在管道中使用的代码的副本。我从上面链接中的最新解答中获得了此代码，但对我而言不起作用。没有任何错误，图像可以正常下载。我的额外代码似乎对文件名没有任何影响，因为它们仍然显示为SHA1哈希。

pipelines.py

class AllenheathPipeline(object):
    def process_item(self, item, spider):
        return item

import scrapy
from scrapy.contrib.pipeline.images import ImagesPipeline
from scrapy.http import Request
from scrapy.exceptions import DropItem

class MyImagesPipeline(ImagesPipeline):

    #Name download version
    def file_path(self, request, response=None, info=None):
        item=request.meta['item'] # Like this you can use all from item, not just url.
        image_guid = request.url.split('/')[-1]
        return 'full/%s' % (image_guid)

    #Name thumbnail version
    def thumb_path(self, request, thumb_id, response=None, info=None):
        image_guid = thumb_id + request.url.split('/')[-1]
        return 'thumbs/%s/%s.jpg' % (thumb_id, image_guid)

    def get_media_requests(self, item, info):
        #yield Request(item['images']) # Adding meta. Dunno how to put it in one line :-)
        for image in item['images']:
            yield Request(image)

    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

BOT_NAME = 'allenheath'

SPIDER_MODULES = ['allenheath.spiders']
NEWSPIDER_MODULE = 'allenheath.spiders'

ITEM_PIPELINES = {'scrapy.contrib.pipeline.images.ImagesPipeline': 1}

IMAGES_STORE = 'c:/allenheath/images'

products.py（我的蜘蛛）

import scrapy
import urlparse

from allenheath.items import ProductItem
from scrapy.selector import Selector
from scrapy.http import HtmlResponse

class productsSpider(scrapy.Spider):
    name = "products"
    allowed_domains = ["http://www.allen-heath.com/"]
    start_urls = [
        "http://www.allen-heath.com/ahproducts/ilive-80/",
        "http://www.allen-heath.com/ahproducts/ilive-112/"
    ]

    def parse(self, response):
        for sel in response.xpath('/html'):
            item = ProductItem()
            item['model'] = sel.css('#prodsingleouter > div > div > h2::text').extract() # The value I'd like to use to name my images.
            item['shortdesc'] = sel.css('#prodsingleouter > div > div > h3::text').extract()
            item['desc'] = sel.css('#tab1 #productcontent').extract()
            item['series'] = sel.css('#pagestrip > div > div > a:nth-child(3)::text').extract()
            item['imageorig'] = sel.css('#prodsingleouter > div > div > h2::text').extract()
            item['image_urls'] = sel.css('#tab1 #productcontent .col-sm-9 img').xpath('./@src').extract()
            item['image_urls'] = [urlparse.urljoin(response.url, url) for url in item['image_urls']]
            yield item

items.py

import scrapy

class ProductItem(scrapy.Item):
    model = scrapy.Field()
    itemcode = scrapy.Field()
    shortdesc = scrapy.Field()
    desc = scrapy.Field()
    series = scrapy.Field()
    imageorig = scrapy.Field()
    image_urls = scrapy.Field()
    images = scrapy.Field()

这是我运行蜘蛛程序时从命令提示符处获得的输出的pastebin：http : //pastebin.com/ir7YZFqf

任何帮助将不胜感激！