scrapy 爬取当当网产品分类

#spider部分
import scrapy
from Autopjt.items import AutopjtItem
from scrapy.http import Request

class AutospdSpider(scrapy.Spider):
    name = "autospd"
    allowed_domains = ["dangdang.com"]
    start_urls = ['http://category.dangdang.com/pg1-cid4007379.html']

    def parse(self, response):
        item = AutopjtItem()
        item['name'] =response.xpath('//a[@name="itemlist-title"]/@title').extract()
        item['price'] = response.xpath('//span[@class="price_n"]/text()').extract()
        item['link'] = response.xpath('//a[@name="itemlist-title"]/@href').extract()
        item['comnum'] = response.xpath('//a[@name="itemlist-review"]/text()').extract()
        yield item
        for i in range(1,101):
            url = 'http://category.dangdang.com/pg'+str(i)+'-cid4007379.html'
            yield Request(url,callback=self.parse)

pipeline部分

import codecs
import json

class AutopjtPipeline(object):
    def __init__(self):
        self.file = codecs.open('D:/mydata.json','wb',encoding='utf-8')
    def process_item(self, item, spider):
        for j in range(0,len(item['name'])):
            name = item['name'][j]
            price = item['price'][j]
            comnum = item['comnum'][j]
            link =item['link'][j]
            goods = {'name':name,'price':price,'comnum':comnum,'link':link}
            i = json.dumps(dict(goods),ensure_ascii=False)
            line = i + '\n'
            self.file.write(line)
        return item
    def close_spider(self,spider):
        self.file.close()

item部分

import scrapy

class AutopjtItem(scrapy.Item):
    # define the fields for your item here like:
    # name = scrapy.Field()
    name = scrapy.Field()
    price = scrapy.Field()
    link = scrapy.Field()
    comnum = scrapy.Field()