我已经在同一个文件中为网络蜘蛛创建了从不同网站获取数据的文件。当我自己运行每个蜘蛛时，我可以成功地将scraped数据从models.py文件传递到postgresql表中。但是当我使用api同时运行两个蜘蛛时，每个蜘蛛的表都会被创建，但由于某些原因，没有数据可以被抓到它们中。我认为这可能与每次运行蜘蛛时调用定义的Pipeline类的方式有关，但由于文档没有真正显示实现的内部结构，因此很难说。从我提供的代码中，我是否有正确的设置将数据流水线化到两个不同的表中？
Models.py
from sqlalchemy.orm import sessionmaker
from models import Tickets, Tickets3, db_connect, create_vs_tickets_table, create_tc_tickets_table
class ComparatorPipeline(object):
"""Price comparison pipeline for storing scraped items in the database"""
def __init__(self):
"""
Initializes database connection and sessionmaker.
Creates deals table.
"""
engine = db_connect()
create_vs_tickets_table(engine)
create_tc_tickets_table(engine)
self.Session = sessionmaker(bind=engine)
def process_item(self, item, spider):
"""Save tickets in the database.
This method is called for every item pipeline component.
"""
if spider.name == "comparator":
session = self.Session()
ticket = Tickets(**item)
try:
session.add(ticket)
session.commit()
except:
session.rollback()
raise
finally:
session.close()
return item
elif spider.name == "comparator3":
session = self.Session()
ticket3 = Tickets3(**item)
try:
session.add(ticket3)
session.commit()
except:
session.rollback()
raise
finally:
session.close()
return item
蜘蛛定义
import scrapy
import re
import json
from scrapy.crawler import CrawlerProcess
from scrapy import Request
from scrapy.contrib.spiders import CrawlSpider , Rule
from scrapy.selector import HtmlXPathSelector
from scrapy.selector import Selector
from scrapy.contrib.loader import ItemLoader
from scrapy.contrib.loader import XPathItemLoader
from scrapy.contrib.loader.processor import Join, MapCompose
from concert_comparator.items import ComparatorItem, ComparatorItem3
from urlparse import urljoin
from scrapy.crawler import CrawlerRunner
from twisted.internet import reactor, defer
from scrapy.utils.log import configure_logging
bandname = raw_input("Enter a bandname \n")
vs_url = "http://www.vividseats.com/concerts/" + bandname + "-tickets.html"
tc_url = "https://www.ticketcity.com/concerts/" + bandname + "-tickets.html"
class MySpider(CrawlSpider):
handle_httpstatus_list = [416]
name = 'comparator'
allowed_domains = ["www.vividseats.com"]
start_urls = [vs_url]
tickets_list_xpath = './/*[@itemtype="http://schema.org/Event"]'
def parse_json(self, response):
loader = response.meta['loader']
jsonresponse = json.loads(response.body_as_unicode())
ticket_info = jsonresponse.get('tickets')
price_list = [i.get('p') for i in ticket_info]
if len(price_list) > 0:
str_Price = str(price_list[0])
ticketPrice = unicode(str_Price, "utf-8")
loader.add_value('ticketPrice', ticketPrice)
else:
ticketPrice = unicode("sold out", "utf-8")
loader.add_value('ticketPrice', ticketPrice)
return loader.load_item()
def parse_price(self, response):
loader = response.meta['loader']
ticketsLink = loader.get_output_value("ticketsLink")
json_id_list= re.findall(r"(\d+)[^-]*$", ticketsLink)
json_id= "".join(json_id_list)
json_url = "http://www.vividseats.com/javascript/tickets.shtml?productionId=" + json_id
yield scrapy.Request(json_url, meta={'loader': loader}, callback = self.parse_json, dont_filter = True)
def parse(self, response):
"""
# """
selector = HtmlXPathSelector(response)
# iterate over tickets
for ticket in selector.select(self.tickets_list_xpath):
loader = XPathItemLoader(ComparatorItem(), selector=ticket)
# define loader
loader.default_input_processor = MapCompose(unicode.strip)
loader.default_output_processor = Join()
# iterate over fields and add xpaths to the loader
loader.add_xpath('eventName' , './/*[@class="productionsEvent"]/text()')
loader.add_xpath('eventLocation' , './/*[@class = "productionsVenue"]/span[@itemprop = "name"]/text()')
loader.add_xpath('ticketsLink' , './/*/a[@class = "btn btn-primary"]/@href')
loader.add_xpath('eventDate' , './/*[@class = "productionsDate"]/text()')
loader.add_xpath('eventCity' , './/*[@class = "productionsVenue"]/span[@itemprop = "address"]/span[@itemprop = "addressLocality"]/text()')
loader.add_xpath('eventState' , './/*[@class = "productionsVenue"]/span[@itemprop = "address"]/span[@itemprop = "addressRegion"]/text()')
loader.add_xpath('eventTime' , './/*[@class = "productionsTime"]/text()')
print "Here is ticket link \n" + loader.get_output_value("ticketsLink")
#sel.xpath("//span[@id='PractitionerDetails1_Label4']/text()").extract()
ticketsURL = "concerts/" + bandname + "-tickets/" + bandname + "-" + loader.get_output_value("ticketsLink")
ticketsURL = urljoin(response.url, ticketsURL)
yield scrapy.Request(ticketsURL, meta={'loader': loader}, callback = self.parse_price, dont_filter = True)
class MySpider3(CrawlSpider):
handle_httpstatus_list = [416]
name = 'comparator3'
allowed_domains = ["www.ticketcity.com"]
start_urls = [tc_url]
tickets_list_xpath = './/div[@class = "vevent"]'
def parse_json(self, response):
loader = response.meta['loader']
jsonresponse = json.loads(response.body_as_unicode())
ticket_info = jsonresponse.get('B')
price_list = [i.get('P') for i in ticket_info]
if len(price_list) > 0:
str_Price = str(price_list[0])
ticketPrice = unicode(str_Price, "utf-8")
loader.add_value('ticketPrice', ticketPrice)
else:
ticketPrice = unicode("sold out", "utf-8")
loader.add_value('ticketPrice', ticketPrice)
return loader.load_item()
def parse_price(self, response):
print "parse price function entered \n"
loader = response.meta['loader']
event_City = response.xpath('.//span[@itemprop="addressLocality"]/text()').extract()
eventCity = ''.join(event_City)
loader.add_value('eventCity' , eventCity)
event_State = response.xpath('.//span[@itemprop="addressRegion"]/text()').extract()
eventState = ''.join(event_State)
loader.add_value('eventState' , eventState)
event_Date = response.xpath('.//span[@class="event_datetime"]/text()').extract()
eventDate = ''.join(event_Date)
loader.add_value('eventDate' , eventDate)
ticketsLink = loader.get_output_value("ticketsLink")
json_id_list= re.findall(r"(\d+)[^-]*$", ticketsLink)
json_id= "".join(json_id_list)
json_url = "https://www.ticketcity.com/Catalog/public/v1/events/" + json_id + "/ticketblocks?P=0,99999999&q=0&per_page=250&page=1&sort=p.asc&f.t=s&_=1436642392938"
yield scrapy.Request(json_url, meta={'loader': loader}, callback = self.parse_json, dont_filter = True)
def parse(self, response):
"""
# """
selector = HtmlXPathSelector(response)
# iterate over tickets
for ticket in selector.select(self.tickets_list_xpath):
loader = XPathItemLoader(ComparatorItem(), selector=ticket)
# define loader
loader.default_input_processor = MapCompose(unicode.strip)
loader.default_output_processor = Join()
# iterate over fields and add xpaths to the loader
loader.add_xpath('eventName' , './/span[@class="summary listingEventName"]/text()')
loader.add_xpath('eventLocation' , './/div[@class="divVenue location"]/text()')
loader.add_xpath('ticketsLink' , './/a[@class="divEventDetails url"]/@href')
#loader.add_xpath('eventDateTime' , '//div[@id="divEventDate"]/@title') #datetime type
#loader.add_xpath('eventTime' , './/*[@class = "productionsTime"]/text()')
print "Here is ticket link \n" + loader.get_output_value("ticketsLink")
#sel.xpath("//span[@id='PractitionerDetails1_Label4']/text()").extract()
ticketsURL = "https://www.ticketcity.com/" + loader.get_output_value("ticketsLink")
ticketsURL = urljoin(response.url, ticketsURL)
yield scrapy.Request(ticketsURL, meta={'loader': loader}, callback = self.parse_price, dont_filter = True)
configure_logging()
runner = CrawlerRunner()
@defer.inlineCallbacks
def crawl():
yield runner.crawl(MySpider)
yield runner.crawl(MySpider3)
reactor.stop()
crawl()
reactor.run()
答案 0 :(得分：1)
我不太了解您的问题但是我看到它有两个表，两个不同的类代表数据库条目（Tickets和Tickets3）和一个管道将它们保存到数据库中。
这个单一的管道被两个蜘蛛的结果调用。为什么不使用spider函数中的process_item变量来区分不同的元素？蜘蛛有一个名字，所以你有工具可以看到哪个蜘蛛发送物品来处理。
答案 1 :(得分：0)
将custom_settings添加到蜘蛛
class MySpider(CrawlSpider):
custom_settings = {
'ITEM_PIPELINES': {
'pipelines.ComparatorPipeline': 400
}
}
handle_httpstatus_list = [416]
并禁用设置中的项目管道列表
# ITEM_PIPELINES = {
# }