我正在使用 scrapy 框架报废一个网站，并且在单击 javascript 链接以打开另一个页面时遇到问题。
我可以将页面上的代码标识为：
<a class="Page" alt="Click to view job description" title="Click to view job description" href="javascript:sysSubmitForm('frmSR1');">Accountant </a>
任何人都可以建议我如何在 scaroy 中执行该 javascript 并通过我可以从该页面获取数据来获取另一个页面。
提前致谢
查看下面关于如何将scrapy与硒一起使用的片段。爬网速度会变慢，因为您不仅要下载 html，而且还可以完全访问 DOM。
注意：我已复制粘贴此代码段，因为之前提供的链接不再有效。
# Snippet imported from snippets.scrapy.org (which no longer works)
from scrapy.contrib.spiders import CrawlSpider, Rule
from scrapy.contrib.linkextractors.sgml import SgmlLinkExtractor
from scrapy.selector import HtmlXPathSelector
from scrapy.http import Request
from selenium import selenium
class SeleniumSpider(CrawlSpider):
name = "SeleniumSpider"
start_urls = ["http://www.domain.com"]
rules = (
Rule(SgmlLinkExtractor(allow=('\.html', )),
callback='parse_page',follow=True),
)
def __init__(self):
CrawlSpider.__init__(self)
self.verificationErrors = []
self.selenium = selenium("localhost", 4444, "*chrome", "http://www.domain.com")
self.selenium.start()
def __del__(self):
self.selenium.stop()
print self.verificationErrors
CrawlSpider.__del__(self)
def parse_page(self, response):
item = Item()
hxs = HtmlXPathSelector(response)
#Do some XPath selection with Scrapy
hxs.select('//div').extract()
sel = self.selenium
sel.open(response.url)
#Wait for javscript to load in Selenium
time.sleep(2.5)
#Do some crawling of javascript created content with Selenium
sel.get_text("//div")
yield item
如果你想查看一个相当庞大的功能代码库，它使用了 scrapy 和 selenium，请查看https://github.com/nicodjimenez/bus_catchers。这是一个更简单的例子。
# stripped down BoltBus script
from selenium import webdriver
from selenium.common.exceptions import TimeoutException
from selenium.webdriver.support.ui import WebDriverWait
from selenium.webdriver.support import expected_conditions as EC
from selenium.webdriver.common.keys import Keys
from scrapy.selector import HtmlXPathSelector
from scrapy.http import Response
from scrapy.http import TextResponse
import time
# set dates, origin, destination
cityOrigin="Baltimore"
cityDeparture="New York"
day_array=[0]
browser = webdriver.Firefox()
# we are going the day of the days of the month from 15,16,...,25
# there is a discrepancy between the index of the calendar days and the day itself: for example day[10] may correspond to Feb 7th
for day in day_array:
# Create a new instance of the Firefox driver
browser.get("http://www.boltbus.com")
# click on "region" tab
elem_0=browser.find_element_by_id("ctl00_cphM_forwardRouteUC_lstRegion_textBox")
elem_0.click()
time.sleep(5)
# select Northeast
elem_1=browser.find_element_by_partial_link_text("Northeast")
elem_1.click()
time.sleep(5)
# click on origin city
elem_2=browser.find_element_by_id("ctl00_cphM_forwardRouteUC_lstOrigin_textBox")
elem_2.click()
time.sleep(5)
# select origin city
elem_3=browser.find_element_by_partial_link_text(cityOrigin)
elem_3.click()
time.sleep(5)
# click on destination city
elem_4=browser.find_element_by_id("ctl00_cphM_forwardRouteUC_lstDestination_textBox")
elem_4.click()
time.sleep(5)
# select destination city
elem_5=browser.find_element_by_partial_link_text(cityDeparture)
elem_5.click()
time.sleep(5)
# click on travel date
travel_date_elem=browser.find_element_by_id("ctl00_cphM_forwardRouteUC_imageE")
travel_date_elem.click()
# gets day rows of table
date_rows=browser.find_elements_by_class_name("daysrow")
# select actual day (use variable day)
# NOTE: you must make sure these day elements are "clickable"
days=date_rows[0].find_elements_by_xpath("..//td")
days[day].click()
time.sleep(3)
# retrieve actual departure date from browser
depart_date_elem=browser.find_element_by_id("ctl00_cphM_forwardRouteUC_txtDepartureDate")
depart_date=str(depart_date_elem.get_attribute("value"))
# PARSE TABLE
# convert html to "nice format"
text_html=browser.page_source.encode('utf-8')
html_str=str(text_html)
# this is a hack that initiates a "TextResponse" object (taken from the Scrapy module)
resp_for_scrapy=TextResponse('none',200,{},html_str,[],None)
# takes a "TextResponse" object and feeds it to a scrapy function which will convert the raw HTML to a XPath document tree
hxs=HtmlXPathSelector(resp_for_scrapy)
# the | sign means "or"
table_rows=hxs.select('//tr[@class="fareviewrow"] | //tr[@class="fareviewaltrow"]')
row_ct=len(table_rows)
for x in xrange(row_ct):
cur_node_elements=table_rows[x]
travel_price=cur_node_elements.select('.//td[@class="faresColumn0"]/text()').re("\d{1,3}\.\d\d")
# I use a mixture of xpath selectors to get me to the right location in the document, and regular expressions to get the exact data
# actual digits of time
depart_time_num=cur_node_elements.select('.//td[@class="faresColumn1"]/text()').re("\d{1,2}\:\d\d")
# AM or PM (time signature)
depart_time_sig=cur_node_elements.select('.//td[@class="faresColumn1"]/text()').re("[AP][M]")
# actual digits of time
arrive_time_num=cur_node_elements.select('.//td[@class="faresColumn2"]/text()').re("\d{1,2}\:\d\d")
# AM or PM (time signature)
arrive_time_sig=cur_node_elements.select('.//td[@class="faresColumn2"]/text()').re("[AP][M]")
print "Depart date: " + depart_date
print "Depart time: " + depart_time_num[0] + " " + depart_time_sig[0]
print "Arrive time: " + arrive_time_num[0] + " " + arrive_time_sig[0]
print "Cost: " + "$" + travel_price[0]
print "\n"
据我所知，通过 urrlib2 和 urllib 实现的 scrappy 爬虫显然不适用于 js。例如，对于使用 js，您可以使用 qt webkit 或 selenium。或者您可以在页面上找到所有 ajax 链接，并查看如何实现与服务器的数据交换并间接向服务器 api 发送响应。