- CrawlSpider:类，Spider的一个子类
- 全站数据爬取的方式
- 基于Spider：手动请求
- 基于CrawlSpider
- CrawlSpider的使用：
- 创建一个工程
- cd XXX
- 创建爬虫文件（CrawlSpider）：
- scrapy genspider -t crawl xxx www.xxxx.com
- 链接提取器：
- 作用：根据指定的规则（allow）进行指定链接的提取
- 规则解析器：
- 作用：将链接提取器提取到的链接进行指定规则（callback）的解析
#需求：爬取sun网站中的编号，新闻标题，新闻内容，标号
- 分析：爬取的数据没有在同一张页面中。
- 1.可以使用链接提取器提取所有的页码链接
- 2.让链接提取器提取所有的新闻详情页的链接
本次案例建议使用代理IP,芝麻代理注册即可每天使用免费ip
import scrapy
from scrapy.linkextractors import LinkExtractor
from scrapy.spiders import CrawlSpider, Rule
from sunPro.items import SunproItem,DetailItem
class SunSpider(CrawlSpider):
name = 'sun'
# allowed_domains = ['']
start_urls = ['https://wz.sun0769.com/political/index/politicsNewest?id=1&page=']
#链接提取器：根据指定规则(allows=“正则”)进行指定连接提取,从start_urls中提取
link=LinkExtractor(allow=r'id=1&page=\d+')
link_detail=LinkExtractor(allow=r'id=\d+')
rules = (
#规则解析器:将链接提取器提取到的链接进行指定规则的解析
Rule(link, callback='parse_item', follow=True),
# follow=True：可以将链接提取器 继续作用到 连接提取器提取到的链接 所对应的页面中 即例如：在第2个页面中提取第3个页面链接 ...
Rule(link_detail,callback='parse_detail')
)
#以下两个方法不可以实现请求传参！
#解析问题编号和问题标题
#如何将两个方法解析到的数据存到同一个item中，存到两个item中
def parse_item(self, response):
li_list=response.xpath('/html/body/div[2]/div[3]/ul[2]/li')
for li in li_list:
p_num=li.xpath('./span[1]/text()').extract_first()
p_title=li.xpath('./span[3]/a/text()').extract_first()
# print(p_num,p_title)
item=SunproItem()
item['p_title']=p_title
item['p_num']=p_num
yield item
#解析问题具体内容和编号
def parse_detail(self,response):
p_content=response.xpath('/html/body/div[3]/div[2]/div[2]/div[2]/pre/text()').extract_first()
p_id=response.xpath('/html/body/div[3]/div[2]/div[2]/div[1]/span[4]/text()').extract_first()
# print(p_id,p_content)
if not p_id:
print('已处理空值！！！！！！！！！！！！！！！！！！！！！！！！！！！！！！！！！！！！！！')
else:
p_id=p_id[3:]
item=DetailItem()
item['p_content']=p_content
item['p_id']=p_id
yield item# Define your item pipelines here
#
# Don't forget to add your pipeline to the ITEM_PIPELINES setting
# See: https://docs.scrapy.org/en/latest/topics/item-pipeline.html
# useful for handling different item types with a single interface
from itemadapter import ItemAdapter
import pymysql
class SunproPipeline:
def process_item(self, item, spider):
#如何判断是那个item
if item.__class__.__name__== 'SunproItem':
print(item['p_num'],item['p_title'])
else:
print(item['p_id'],item['p_content'])
return item
class mysqlPileLine:
conn=None
cursor = None
def open_spider(self,spider):
self.coon = pymysql.Connect(host='127.0.0.1',user='root',password='123456',db='rxkc',charset='utf8')
def process_item(self, item, spider):
self.cursor=self.coon.cursor()
try:
if item.__class__.__name__ == 'SunproItem':
self.cursor.execute('insert into sun values("%s","%s")'%(item["p_num"],item["p_title"]))
self.coon.commit()
else:
self.cursor.execute('insert into sunn values("%s","%s")' % (item["p_id"], item["p_content"]))
self.coon.commit()
except Exception as e:
print(e)
self.coon.rollback()
return item
def close_spider(self,spider):
self.cursor.close()
self.coon.close()# Define here the models for your spider middleware
#
# See documentation in:
# Define here the models for your spider middleware
#
# See documentation in:
# https://docs.scrapy.org/en/latest/topics/spider-middleware.html
from scrapy import signals
# useful for handling different item types with a single interface
from itemadapter import is_item, ItemAdapter
import random
class SunproDownloaderMiddleware:
user_agent_list = [
"Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.1 "
"(KHTML, like Gecko) Chrome/22.0.1207.1 Safari/537.1",
"Mozilla/5.0 (X11; CrOS i686 2268.111.0) AppleWebKit/536.11 "
"(KHTML, like Gecko) Chrome/20.0.1132.57 Safari/536.11",
"Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/536.6 "
"(KHTML, like Gecko) Chrome/20.0.1092.0 Safari/536.6",
"Mozilla/5.0 (Windows NT 6.2) AppleWebKit/536.6 "
"(KHTML, like Gecko) Chrome/20.0.1090.0 Safari/536.6",
"Mozilla/5.0 (Windows NT 6.2; WOW64) AppleWebKit/537.1 "
"(KHTML, like Gecko) Chrome/19.77.34.5 Safari/537.1",
"Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/536.5 "
"(KHTML, like Gecko) Chrome/19.0.1084.9 Safari/536.5",
"Mozilla/5.0 (Windows NT 6.0) AppleWebKit/536.5 "
"(KHTML, like Gecko) Chrome/19.0.1084.36 Safari/536.5",
"Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/536.3 "
"(KHTML, like Gecko) Chrome/19.0.1063.0 Safari/536.3",
"Mozilla/5.0 (Windows NT 5.1) AppleWebKit/536.3 "
"(KHTML, like Gecko) Chrome/19.0.1063.0 Safari/536.3",
"Mozilla/5.0 (Macintosh; Intel Mac OS X 10_8_0) AppleWebKit/536.3 "
"(KHTML, like Gecko) Chrome/19.0.1063.0 Safari/536.3",
"Mozilla/5.0 (Windows NT 6.2) AppleWebKit/536.3 "
"(KHTML, like Gecko) Chrome/19.0.1062.0 Safari/536.3",
"Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/536.3 "
"(KHTML, like Gecko) Chrome/19.0.1062.0 Safari/536.3",
"Mozilla/5.0 (Windows NT 6.2) AppleWebKit/536.3 "
"(KHTML, like Gecko) Chrome/19.0.1061.1 Safari/536.3",
"Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/536.3 "
"(KHTML, like Gecko) Chrome/19.0.1061.1 Safari/536.3",
"Mozilla/5.0 (Windows NT 6.1) AppleWebKit/536.3 "
"(KHTML, like Gecko) Chrome/19.0.1061.1 Safari/536.3",
"Mozilla/5.0 (Windows NT 6.2) AppleWebKit/536.3 "
"(KHTML, like Gecko) Chrome/19.0.1061.0 Safari/536.3",
"Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/535.24 "
"(KHTML, like Gecko) Chrome/19.0.1055.1 Safari/535.24",
"Mozilla/5.0 (Windows NT 6.2; WOW64) AppleWebKit/535.24 "
"(KHTML, like Gecko) Chrome/19.0.1055.1 Safari/535.24"
]
PROXY_http = [
'125.106.138.41:4234',
'42.6.114.117:7018',
]
PROXY_https = [
'110.89.123.129:4213',
'118.123.40.30:4231',
'42.6.114.104:2687'
]
# 拦截请求
def process_request(self, request, spider):
request.headers['User-Agent'] = random.choice(self.user_agent_list)
# request.meta['proxy'] = 'https://42.6.114.99:9702'
return None
def process_response(self, request, response, spider):
# Called with the response returned from the downloader.
# Must either;
# - return a Response object
# - return a Request object
# - or raise IgnoreRequest
return response
def process_exception(self, request, exception, spider):
# 拦截发生异常的请求
if request.url.split(':')[0] == 'http':
# 代理
request.meta['proxy'] = 'http://' + random.choice(self.PROXY_http)
else:
request.meta['proxy'] = 'https://' + random.choice(self.PROXY_https)
return request # 将修正之后的请求对象进行重新的请求发送
import scrapy
class SunproItem(scrapy.Item):
# define the fields for your item here like:
# name = scrapy.Field()
p_num = scrapy.Field()
p_title=scrapy.Field()
class DetailItem(scrapy.Item):
p_content = scrapy.Field()
p_id =scrapy.Field()连接一下两个表的结果：
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