scarpy_流程
scrapy 中间键
review
1.
pip install wheel
pip install twisted
pip install pywin32
pip install scrapy
2.
scrapy startproject ProName
cd ProName
scrapy genspider projectName www.xxx.com
3.
目录结构:
spider: 放置一个爬虫文件
item:
xxx = Filed()
pipeline:
- process_item():
- open_spider():
- close_spider():
setting: 配置文件
4.爬虫文件
- name:
- start_urls:
- parse(self,response):
- xpath():列表元素Selector对象.extract()
- 持久化存储:
-终端指令: 只可将parse方法的返回值进行本地文件的持久化存储
- scrapy crawl xxx -o ./xxx.csv
- 管道:
1. 数据解析
2. 将解析到的数据封装到item类型的对象
3. 通过yield向管道提交item对象
4. 在管道的process_item 方法中执行io操作,进行持久化配置
5. 在配置文件中开启管道
注意: process_item 方法中返回值的作业:
- 手动请求的发送:
- yield scrapy.Request(url,callback)
# -*- coding: utf-8 -*-
# Define here the models for your spider middleware
#
# See documentation in:
# https://doc.scrapy.org/en/latest/topics/spider-middleware.html
import random
from scrapy import signals
class MiddleproSpiderMiddleware(object):
# Not all methods need to be defined. If a method is not defined,
# scrapy acts as if the spider middleware does not modify the
# passed objects.
@classmethod
def from_crawler(cls, crawler):
# This method is used by Scrapy to create your spiders.
s = cls()
crawler.signals.connect(s.spider_opened, signal=signals.spider_opened)
return s
def process_spider_input(self, response, spider):
# Called for each response that goes through the spider
# middleware and into the spider.
# Should return None or raise an exception.
return None
def process_spider_output(self, response, result, spider):
# Called with the results returned from the Spider, after
# it has processed the response.
# Must return an iterable of Request, dict or Item objects.
for i in result:
yield i
def process_spider_exception(self, response, exception, spider):
# Called when a spider or process_spider_input() method
# (from other spider middleware) raises an exception.
# Should return either None or an iterable of Response, dict
# or Item objects.
pass
def process_start_requests(self, start_requests, spider):
# Called with the start requests of the spider, and works
# similarly to the process_spider_output() method, except
# that it doesn’t have a response associated.
# Must return only requests (not items).
for r in start_requests:
yield r
def spider_opened(self, spider):
spider.logger.info('Spider opened: %s' % spider.name)
class MiddleproDownloaderMiddleware(object):
# Not all methods need to be defined. If a method is not defined,
# scrapy acts as if the downloader middleware does not modify the
# passed objects.
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"
]
# 可选备用的代理IP
PROXY_http = [
'153.180.102.104:80',
'195.208.131.189:56055',
]
PROXY_https = [
'120.83.49.90:9000',
'95.189.112.214:35508',
]
@classmethod
def from_crawler(cls, crawler):
# This method is used by Scrapy to create your spiders.
s = cls()
crawler.signals.connect(s.spider_opened, signal=signals.spider_opened)
return s
# 拦截所有未发生异常的请求
def process_request(self, request, spider):
# Called for each request that goes through the downloader
# middleware.
# Must either:
# - return None: continue processing this request
# - or return a Response object
# - or return a Request object
# - or raise IgnoreRequest: process_exception() methods of
# installed downloader middleware will be called
# 使用UA池进行请求的UA伪装
print('this is process_request')
request.headers['User_Agent'] = random.choice(self.user_agent_list)
print('User_Agent', request.headers['User_Agent'])
# #使用代理池进行请求代理ip的设置
# if request.url.split(':')[0] == 'http':
# request.meta['proxy'] = random.choice(self.PROXY_http)
# else:
# request.meta['proxy'] = random.choice(self.PROXY_https)
return None
# 拦截所有的响应
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
# 拦截到产生异常的请求
def process_exception(self, request, exception, spider):
# Called when a download handler or a process_request()
# (from other downloader middleware) raises an exception.
# Must either:
# - return None: continue processing this exception
# - return a Response object: stops process_exception() chain
# - return a Request object: stops process_exception() chain
print('this is process_exception')
if request.url.split(':')[0]:
request.meta['proxy'] = random.choice(self.PROXY_http)
else:
request.meta['proxy'] = random.choice(self.PROXY_https)
def spider_opened(self, spider):
spider.logger.info('Spider opened: %s' % spider.name)
爬取电影网
https://www.4567tv.tv/frim/index1.html
movie_pro.py
# -*- coding: utf-8 -*-
import scrapy
from movie.items import MovieItem
class MoveProSpider(scrapy.Spider):
name = 'movie_pro'
# allowed_domains = ['www.xxx.com']
start_urls = ['https://www.4567tv.tv/frim/index1.html']
# 解析详情页面的数据
def parse_detail(self, response):
# response,meta 返回接受到的meta 字典
item = response.meta['item']
actor = response.xpath('/html/body/div[1]/div/div/div/div[2]/p[3]/a/text()').extract_first()
item['actor'] = actor
yield item
def parse(self, response):
li_list = response.xpath('//li[@class="col-md-6 col-sm-4 col-xs-3"]')
for li in li_list:
item = MovieItem()
name = li.xpath('./div/a/@title').extract_first()
detail_url = 'https://www.4567tv.tv' + li.xpath('./div/a/@href').extract_first()
item['name'] = name
# meta 参数: 请求传参,meta字典会传递给回调函数的response参数
yield scrapy.Request(url=detail_url, callback=self.parse_detail, meta={'item': item})
网易
# -*- coding: utf-8 -*-
# Define here the models for your spider middleware
#
# See documentation in:
# https://doc.scrapy.org/en/latest/topics/spider-middleware.html
from scrapy import signals
from scrapy.http import HtmlResponse
from time import sleep
class WangyiproSpiderMiddleware(object):
# Not all methods need to be defined. If a method is not defined,
# scrapy acts as if the spider middleware does not modify the
# passed objects.
@classmethod
def from_crawler(cls, crawler):
# This method is used by Scrapy to create your spiders.
s = cls()
crawler.signals.connect(s.spider_opened, signal=signals.spider_opened)
return s
def process_spider_input(self, response, spider):
# Called for each response that goes through the spider
# middleware and into the spider.
# Should return None or raise an exception.
return None
def process_spider_output(self, response, result, spider):
# Called with the results returned from the Spider, after
# it has processed the response.
# Must return an iterable of Request, dict or Item objects.
for i in result:
yield i
def process_spider_exception(self, response, exception, spider):
# Called when a spider or process_spider_input() method
# (from other spider middleware) raises an exception.
# Should return either None or an iterable of Response, dict
# or Item objects.
pass
def process_start_requests(self, start_requests, spider):
# Called with the start requests of the spider, and works
# similarly to the process_spider_output() method, except
# that it doesn’t have a response associated.
# Must return only requests (not items).
for r in start_requests:
yield r
def spider_opened(self, spider):
spider.logger.info('Spider opened: %s' % spider.name)
class WangyiproDownloaderMiddleware(object):
# Not all methods need to be defined. If a method is not defined,
# scrapy acts as if the downloader middleware does not modify the
# passed objects.
@classmethod
def from_crawler(cls, crawler):
# This method is used by Scrapy to create your spiders.
s = cls()
crawler.signals.connect(s.spider_opened, signal=signals.spider_opened)
return s
def process_request(self, request, spider):
# Called for each request that goes through the downloader
# middleware.
# Must either:
# - return None: continue processing this request
# - or return a Response object
# - or return a Request object
# - or raise IgnoreRequest: process_exception() methods of
# installed downloader middleware will be called
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
# 如何获取动态加载出来的数据
bro = spider.bro
bro.get(url=request.url)
sleep(3)
# 包含了动态加载出来的新闻数据
page_text = bro.page_source
sleep(3)
return HtmlResponse(url=spider.bro.current_url, body=page_text, encoding='utf-8', request=request)
def process_exception(self, request, exception, spider):
# Called when a download handler or a process_request()
# (from other downloader middleware) raises an exception.
# Must either:
# - return None: continue processing this exception
# - return a Response object: stops process_exception() chain
# - return a Request object: stops process_exception() chain
pass
def spider_opened(self, spider):
spider.logger.info('Spider opened: %s' % spider.name)
wangyi.py
# -*- coding: utf-8 -*-
import scrapy
from selenium import webdriver
"""
在scrapy中使用selenium的编码流程:
1.在spider的构造方法中创建一个浏览器对象(作为当前spider的一个属性)
2.重写spider的一个方法closed(self,spider),在该方法中执行浏览器关闭的操作
3.在下载中间键得process_response方法中,通过spider参数获取浏览器对象
4.在中间键得process_response定制基于浏览器自动化的操作代码(获取动态加载出来的页面源码数据)
5.实例化一个响应对象,且将page_source返回的页面源码封装到该对象中
6.返回该新的响应对象
"""
class WangyiSpider(scrapy.Spider):
name = 'wangyi'
# allowed_domains = ['www.example.com']
start_urls = ['http://war.163.com/']
def __init__(self):
self.bro = webdriver.Chrome(executable_path=r'C:\Users\Administrator\Desktop\爬虫+数据\day_03_爬虫\chromedriver.exe')
def parse(self, response):
div_list = response.xpath('//div[@class="data_row news_article clearfix "]')
for div in div_list:
title = div.xpath('.//div[@class="news_title"]/h3/a/text()').extract_first()
print(title)
def closed(self, spider):
print('关闭浏览器对象!')
self.bro.quit()
