两个关键字之间的scrapy xpath

时间:2014-04-11 02:16:08

标签: python xpath scrapy

我试图在两个关键字之间提取一些文字信息,如下所示:

item['duties']=titles.select('.//span/text()[following-sibling::*[text()="Qualifications/Duties" and preceding-sibling::*text()="Entity Information"]').extract()

蜘蛛:

from scrapy.contrib.spiders import CrawlSpider, Rule
from scrapy.contrib.linkextractors.sgml import SgmlLinkExtractor
from scrapy.http import request
from scrapy.selector import HtmlXPathSelector
from health.items import HealthItem

class healthspider(CrawlSpider):

    name="health"
    allowed_domains=['mysite']
    start_urls=['myurl']

    rules=(
    Rule(SgmlLinkExtractor(allow=("search/",)), callback="parse_health", follow=True),
    Rule(SgmlLinkExtractor(allow=("url",)),callback="parse_job",follow=True),
    )


    def parse_job(self, response):
        hxs=HtmlXPathSelector(response)
    titles=hxs.select('//*[@itemprop="description"]')
    items = []

    for titles in titles:
        item=HealthItem()
        item['duties']=titles.select('.//span[following-sibling::*[text()="Qualifications/Duties" and preceding-sibling::*text()="Entity Information"]/text()').extract()
        item['entity_info']=titles.select('.//span/text()[45]').extract()           items.append(item)
    print items
    return items

但我得到一个错误说:

raise ValueError("Invalid XPath: %s" % query)
    exceptions.ValueError: Invalid XPath: .//span/text()[following-sibling::*[text()="Qualifications/Duties" and preceding-sibling::*text()="Entity Information"]

有没有办法在我的蜘蛛中定义这样的xpath?

1 个答案:

答案 0 :(得分:1)

有几个选择:

选择node()测试(文本节点和元素节点)

In [1]: sel.xpath(""".//node()[preceding-sibling::*="Qualifications/Duties"]
                              [following-sibling::*="Entity Information"]""").extract()
Out[1]: 
[u'<br>',
 u'Texas Health Presbyterian Allen is currently in search of a Registered Nurse to help meet the growing needs of our Day Surgery Department to work PRN in Day Surgery and also float to PACU.',
 u'<br>',
 u'<br>',
 u'<b>Basic Qualifications:</b>',
 u'<br>',
 u'<br>',
 u'*Graduate of an accredited school of nursing',
 u'<br>',
 u'*Valid RN license in the state of Texas',
 u'<br>',
 u'*BLS',
 u'<br>',
 u'*ACLS',
 u'<br>',
 u'*PALS within 6 months of hire',
 u'<br>',
 u'*Minimum of 1 - 3 years experience as RN in Day Surgery, PACU, Outpatient Surgery, or ICU',
 u'<br>',
 u'*Strong organizational skills and ability to function in a fast paced work environment',
 u'<br>',
 u'*Ability to accept responsibility and show initiative to work without direct supervision',
 u'<br>',
 u'*A high degree of confidentiality, positive interpersonal skills and ability to function in a fast-paced environment',
 u'<br>',
 u'<br>',
 u'<b>Preferred Qualifications:</b>',
 u'<br>',
 u'<br>',
 u'*Three years RN experience in Outpatient Surgery along with some ICU experience.',
 u'<br>',
 u'*PALS',
 u'<br>',
 u'*PACU , Endoscopy or Ambulatory setting',
 u'<br>',
 u'*IV Conscious Sedation',
 u'<br>',
 u'<br>',
 u'<b>Hours/Schedule:</b>',
 u'<br>',
 u'<br>',
 u'*Variable',
 u'<br>',
 u'<br>',
 u'J2WPeriop',
 u'<br>',
 u'<br>']

仅选择文本节点:(“松散”粗线)

In [2]: sel.xpath(""".//text()[preceding-sibling::*="Qualifications/Duties"]
                              [following-sibling::*="Entity Information"]""").extract()
Out[2]: 
[u'Texas Health Presbyterian Allen is currently in search of a Registered Nurse to help meet the growing needs of our Day Surgery Department to work PRN in Day Surgery and also float to PACU.',
 u'*Graduate of an accredited school of nursing',
 u'*Valid RN license in the state of Texas',
 u'*BLS',
 u'*ACLS',
 u'*PALS within 6 months of hire',
 u'*Minimum of 1 - 3 years experience as RN in Day Surgery, PACU, Outpatient Surgery, or ICU',
 u'*Strong organizational skills and ability to function in a fast paced work environment',
 u'*Ability to accept responsibility and show initiative to work without direct supervision',
 u'*A high degree of confidentiality, positive interpersonal skills and ability to function in a fast-paced environment',
 u'*Three years RN experience in Outpatient Surgery along with some ICU experience.',
 u'*PALS',
 u'*PACU , Endoscopy or Ambulatory setting',
 u'*IV Conscious Sedation',
 u'*Variable',
 u'J2WPeriop']

选择所需部分的文本节点兄弟节点+粗体行的文本节点::

In [3]: sel.xpath(""".//*[preceding-sibling::*="Qualifications/Duties"]
                         [following-sibling::*="Entity Information"]/text()
                     |
                     .//text()[preceding-sibling::*="Qualifications/Duties"]
                              [following-sibling::*="Entity Information"]""").extract()
Out[3]: 
[u'Texas Health Presbyterian Allen is currently in search of a Registered Nurse to help meet the growing needs of our Day Surgery Department to work PRN in Day Surgery and also float to PACU.',
 u'Basic Qualifications:',
 u'*Graduate of an accredited school of nursing',
 u'*Valid RN license in the state of Texas',
 u'*BLS',
 u'*ACLS',
 u'*PALS within 6 months of hire',
 u'*Minimum of 1 - 3 years experience as RN in Day Surgery, PACU, Outpatient Surgery, or ICU',
 u'*Strong organizational skills and ability to function in a fast paced work environment',
 u'*Ability to accept responsibility and show initiative to work without direct supervision',
 u'*A high degree of confidentiality, positive interpersonal skills and ability to function in a fast-paced environment',
 u'Preferred Qualifications:',
 u'*Three years RN experience in Outpatient Surgery along with some ICU experience.',
 u'*PALS',
 u'*PACU , Endoscopy or Ambulatory setting',
 u'*IV Conscious Sedation',
 u'Hours/Schedule:',
 u'*Variable',
 u'J2WPeriop']