Question

他在Scrapy中创造了一只蜘蛛： items.py：

from scrapy.item import Item, Field

class dns_shopItem (Item):
     # Define the fields for your item here like:
     # Name = Field ()
     id = Field ()
     idd = Field ()

dns_shop_spider.py：

from scrapy.contrib.spiders import CrawlSpider, Rule
from scrapy.contrib.linkextractors.sgml import SgmlLinkExtractor
from scrapy.contrib.loader.processor import TakeFirst
from scrapy.contrib.loader import XPathItemLoader
from scrapy.selector import HtmlXPathSelector
from dns_shop.items import dns_shopItem
 
class dns_shopLoader (XPathItemLoader):
     default_output_processor = TakeFirst ()
 
class dns_shopSpider (CrawlSpider):
    name = "dns_shop_spider"
    allowed_domains = ["www.playground.ru"]
    start_urls = ["http://www.playground.ru/files/stalker_clear_sky/"]
    rules = (
    Rule (SgmlLinkExtractor (allow = ('/ files / s_t_a_l_k_e_r_chistoe_nebo')), follow = True),
    Rule (SgmlLinkExtractor (allow = ('/ files / s_t_a_l_k_e_r_chistoe_nebo')), callback = 'parse_item'),
    )

    def parse_item (self, response):
        hxs = HtmlXPathSelector (response)
        l = dns_shopLoader (dns_shopItem (), hxs)
        l.add_xpath ('id', "/ html / body / table [2] / tbody / tr [5] / td [2] / table / tbody / tr / td / div [6] / h1/text ()" )
        l.add_xpath ('idd', "/ / html / body / table [2] / tbody / tr [5] / td [2] / table / tbody / tr / td / div [6] / h1/text () ")
        return l.load_item ()

运行以下命令：

scrapy crawl dns_shop_spider-o scarped_data_utf8.csv-t csv

此日志显示Scrapy通过所有必需的URL，但为什么不在启动蜘蛛时写入指定的文件。可能是什么问题？

Answer 1

假设您要关注页面http://www.playground.ru/files/stalker_clear_sky/上的所有链接，并获取要下载的标题，网址和链接：

from scrapy.contrib.spiders import CrawlSpider, Rule
from scrapy.contrib.linkextractors.sgml import SgmlLinkExtractor
from scrapy.contrib.loader.processor import TakeFirst
from scrapy.contrib.loader import XPathItemLoader
from scrapy.selector import HtmlXPathSelector

from scrapy.item import Item, Field


class PlayGroundItem(Item):
    title = Field()
    url = Field()
    download_url = Field()


class PlayGroundLoader(XPathItemLoader):
    default_output_processor = TakeFirst()


class PlayGroundSpider(CrawlSpider):
    name = "playground_spider"
    allowed_domains = ["www.playground.ru"]
    start_urls = ["http://www.playground.ru/files/stalker_clear_sky/"]
    rules = (
        Rule(SgmlLinkExtractor(allow=('/files/s_t_a_l_k_e_r_chistoe_nebo')), follow=True, callback='parse_item'),
    )


    def parse_item(self, response):
        hxs = HtmlXPathSelector(response)
        l = PlayGroundLoader(PlayGroundItem(), hxs)
        l.add_value('url', response.url)
        l.add_xpath('title', "//div[@class='downloads-container clearfix']/h1/text()")
        l.add_xpath('download_url', "//div[@class='files-download-holder']/div/a/@href")

        return l.load_item()

将其保存到spider.py并通过以下方式运行：

scrapy runspider test_scrapy.py -o output.json

然后检查output.json。

希望有所帮助。

Scrapy不会将数据写入文件

1 个答案: