爬虫(四)之分布式爬虫

 01-基于Redis的分布式爬虫（基于RedisCrawlSpider类）

分布式爬虫：
    1.概念：多台机器上可以执行统一爬虫程序，实现网站数据的分布式爬取。
    2.原生的scrapy 是不可以实现分布式爬虫的。
        2.1 调度器无法共享
        2.2 管道无法共享
    3. scrapy-redis组件：专门为scrapy开发的组件。实现分布式爬取
        3.1 下载：pip install scrapy-redis
    4.分布式爬取的流程：
        a. 安装Redis数据库
        b. redis配置文件的配置
        c. redis服务的开启，基于配置配置文件
        d. 创建scrapy工程后，创建基于crawlSpider的爬虫文件
        e. 导入 from scrapy_redis.spiders import RedisCrawlSpider
        f. 然后爬虫文件基于 RedisCrawlSpider 这个类的源文件
            class RedisqiubaiSpider(RedisCrawlSpider):
        g. 修改
            # start_urls = ['https://www.qiushibaike.com/pic/']

            # 调度器队列的名称 该行代码 跟start_urls含义一样
            redis_key = 'qiubaiSpider'
        h. 将项目的管道和调度器 配置成 基于 scrapy-redis的组件
        i. 执行爬虫文件
            scrapy runspider reidsQiubai.py
        j. 在redis的客户端，将起始url 放到调度器的队列中（qiubaiSpider 是调度器队列名称）
            lpush qiubaiSpider https://www.qiushibaike.com/pic/
        k. 查询爬取结果
            lrange redisQiubai:items 0 -1

修改配置文件

# settings.py

ROBOTSTXT_OBEY = False

USER_AGENT = "Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/67.0.3396.87 Safari/537.36"

# 使用scrapy-redis组件中封装好的管道，将每台机器爬取到的数据存储通过该管道存储到redis数据库中，从而实现了多台机器的管道共享。

ITEM_PIPELINES = {
    # 'redisPro.pipelines.RedisproPipeline': 300,
    'scrapy_redis.pipelines.RedisPipeline': 400,

}

# 使用scrapy-redis组件中封装好的调度器，将所有的url存储到该指定的调度器中，从而实现了多台机器的调度器共享。

# 使用scrapy-redis组件的去重队列
DUPEFILTER_CLASS = "scrapy_redis.dupefilter.RFPDupeFilter"
# 使用scrapy-redis组件自己的调度器
SCHEDULER = "scrapy_redis.scheduler.Scheduler"
# 是否允许暂停
SCHEDULER_PERSIST = True

# 如果redis 服务器不在自己本机，则需要如下配置：
# REDIS_HOST = 'redis服务的ip地址'
# REDIS_PORT = 6379

# 创建新项目
scrapy startproject redisPro

cd redisPro/

scrapy genspider -t crawl redisQiubai www.qiushibaike.com/pic/

# redisQiubai.py

# -*- coding: utf-8 -*-
import scrapy
from scrapy.linkextractors import LinkExtractor
from scrapy.spiders import CrawlSpider, Rule

from redisPro.items import RedisproItem

from scrapy_redis.spiders import RedisCrawlSpider


class RedisqiubaiSpider(RedisCrawlSpider):
    name = 'redisQiubai'
    # allowed_domains = ['www.qiushibaike.com/pic/']
    # start_urls = ['https://www.qiushibaike.com/pic/']

    # 调度器队列的名称 该行代码 跟start_urls含义一样
    redis_key = 'qiubaiSpider'

    link = LinkExtractor(allow=r'/pic/page/d+')
    rules = (
        Rule(link, callback='parse_item', follow=True),
    )

    def parse_item(self, response):
        div_list = response.xpath('//*[@id="content-left"]/div')
        for div in div_list:
            img_url = "https:" + div.xpath('.//div[@class="thumb"]/a/img/@src').extract_first()
            item = RedisproItem()
            item['img_url'] = img_url

            yield item

# 切换到爬虫文件的目录
cd redisPro/redisPro/spiders/

# 执行爬虫文件
scrapy runspider redisQiubai.py

将起始url 放到 调度器队列中

查看爬取结果

02-UA池

- 作用：尽可能多的将scrapy工程中的请求伪装成不同类型的浏览器身份。

- 操作流程：

    1.在下载中间件中拦截请求
    2.将拦截到的请求的请求头信息中的UA进行篡改伪装
    3.在配置文件中开启下载中间件

# pipelines.py

# 导包
from scrapy.contrib.downloadermiddleware.useragent import UserAgentMiddleware
import random
# UA池代码的编写（单独给UA池封装一个下载中间件的一个类）
class RandomUserAgent(UserAgentMiddleware):

    def process_request(self, request, spider):
        # 从列表中随机抽选出一个ua值
        ua = random.choice(user_agent_list)
        # ua值进行当前拦截到请求的ua的写入操作
        request.headers.setdefault('User-Agent',ua)


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"
]

03-代理池

- 作用：尽可能多的将scrapy工程中的请求的IP设置成不同的。
- 免费代理ip：http://www.goubanjia.com/
- 操作流程：

    1.在下载中间件中拦截请求
    2.将拦截到的请求的IP修改成某一代理IP
    3.在配置文件中开启下载中间件

# pipelines.py

# 批量对拦截到的请求进行ip更换
# 单独封装下载中间件类
class Proxy(object):
    def process_request(self, request, spider):
        # 对拦截到请求的url进行判断（协议头到底是http还是https）
        # request.url返回值：http://www.xxx.com
        h = request.url.split(':')[0]  # 请求的协议头
        if h == 'https':
            ip = random.choice(PROXY_https)
            request.meta['proxy'] = 'https://'+ip
        else:
            ip = random.choice(PROXY_http)
            request.meta['proxy'] = 'http://' + ip

# 可被选用的代理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',
]

04-selenium在scrapy中的应用

selenium如何被应用到scrapy:
    a)在爬虫文件中导入webdriver类
    b)在爬虫文件的爬虫类的构造方法中进行了浏览器实例化的操作
    c)在爬虫类的closed方法中进行浏览器关闭的操作
    d)在下载中间件的process_response方法中编写执行浏览器自动化的操作    

·需求：爬取的是基于文字的新闻数据（国内，国际，军事，航空）

# -*- 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.http import HtmlResponse
import time

'''
UA池
'''
# 导包
from scrapy.contrib.downloadermiddleware.useragent import UserAgentMiddleware
import random
# UA池代码的编写（单独给UA池封装一个下载中间件的一个类）


class RandomUserAgent(UserAgentMiddleware):

    def process_request(self, request, spider):
        # 从列表中随机抽选出一个ua值
        ua = random.choice(user_agent_list)
        # ua值进行当前拦截到请求的ua的写入操作
        request.headers.setdefault('User-Agent',ua)


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"
]


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.

    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

    # 可以拦截到响应对象(下载器传递给spider的响应对象)
    # request：响应对象对应的请求对象
    # response：拦截到的响应对象
    # spider：爬虫文件中对应的爬虫类的实例
    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

        # 响应对象中存储页面数据的篡改
        # print(request.url)
        if request.url in ['http://news.163.com/domestic/', 'http://news.163.com/air/', 'http://war.163.com/', 'http://news.163.com/world/']:
            spider.bro.get(url=request.url)

            js = 'windows.scrollTo(0, document.body.scrollHeight)'
            spider.bro.execute_script(js)
            # 一定要给浏览器移动的缓冲加载数据的时间
            time.sleep(2)
            # page_text 包含了动态加载出来的页面数据
            page_text = spider.bro.page_source
            # current_url属性 表示 刚才浏览器发起请求所对应的url
            # body: 表示 响应对象所携带的数据值
            return HtmlResponse(url=spider.bro.current_url, body=page_text, encoding='utf-8', request=request)
        else:
            return response


'''
代理池
'''
# 批量对拦截到的请求进行ip更换
# 单独封装下载中间件类


class Proxy(object):
    def process_request(self, request, spider):
        # 对拦截到请求的url进行判断（协议头到底是http还是https）
        # request.url返回值：http://www.xxx.com
        h = request.url.split(':')[0]  # 请求的协议头
        if h == 'https':
            ip = random.choice(PROXY_https)
            request.meta['proxy'] = 'https://'+ip
        else:
            ip = random.choice(PROXY_http)
            request.meta['proxy'] = 'http://' + ip

# 可被选用的代理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',
]

middlewares.py

# -*- coding: utf-8 -*-
import scrapy
from selenium import webdriver
from wangyiPro.items import WangyiproItem


class WangyiSpider(scrapy.Spider):
    name = 'wangyi'
    # allowed_domains = ['https://news.163.com']
    start_urls = ['https://news.163.com/']

    def __init__(self):
        # 实例化一个浏览器对象
        self.bro = webdriver.Chrome(executable_path='./chromedriver 2')

    # 必须在整个爬虫结束后，关闭浏览器
    def closed(self, spider):
        print("爬虫结束！")
        self.bro.quit()

    def parse(self, response):
        lis = response.xpath('//div[@class="ns_area list"]/ul/li')
        indexs = [3, 4, 6, 7]
        # 存储的是 国内，国际，军事，航空 四个板块对应的li标签对象
        li_list = []
        for index in indexs:
            li_list.append(lis[index])
        # 获取四个板块的链接和文字标题
        for li in li_list:
            url = li.xpath('./a/@href').extract_first()
            title = li.xpath('./a/text()').extract_first()

            # headers = {
            #     'Connection': 'close',
            # }

            # print(title, url)
            # 对每一个板块对应的url发起请求，获取页面数据（标题，缩略图，关键字，发布时间，标题的url）
            yield scrapy.Request(url=url, callback=self.parseSecond, meta={'title': title, 'url': url})

    def parseSecond(self, response):
        div_list = response.xpath('//div[@class="data_row news_article clearfix"]')
        # print(len(div_list))
        for div in div_list:
            # 标题
            head = div.xpath('.//div[@class="news_title"]/h3/a/text()').extract_first()
            # 缩略图链接
            img_url = div.xpath('./a/img/@src').extract_first()

            tag = div.xpath('.//div[@class="news_tag"]//text()').extract()
            tags = []
            for i in tag:
                i = i.strip('
 	')
                tags.append(i)
            tag = "".join(tags)

            # 标题链接
            title_url = div.xpath('.//div[@class="news_title"]/h3/a/@href').extract_first()

# -*- coding: utf-8 -*-

# Scrapy settings for wangyiPro project
#
# For simplicity, this file contains only settings considered important or
# commonly used. You can find more settings consulting the documentation:
#
#     https://doc.scrapy.org/en/latest/topics/settings.html
#     https://doc.scrapy.org/en/latest/topics/downloader-middleware.html
#     https://doc.scrapy.org/en/latest/topics/spider-middleware.html

BOT_NAME = 'wangyiPro'

SPIDER_MODULES = ['wangyiPro.spiders']
NEWSPIDER_MODULE = 'wangyiPro.spiders'


# Crawl responsibly by identifying yourself (and your website) on the user-agent
# USER_AGENT = 'wangyiPro (+http://www.yourdomain.com)'
USER_AGENT = "Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/67.0.3396.87 Safari/537.36"

# Obey robots.txt rules
ROBOTSTXT_OBEY = False

# Configure maximum concurrent requests performed by Scrapy (default: 16)
# CONCURRENT_REQUESTS = 32

# Configure a delay for requests for the same website (default: 0)
# See https://doc.scrapy.org/en/latest/topics/settings.html#download-delay
# See also autothrottle settings and docs
#DOWNLOAD_DELAY = 3
# The download delay setting will honor only one of:
#CONCURRENT_REQUESTS_PER_DOMAIN = 16
#CONCURRENT_REQUESTS_PER_IP = 16

# Disable cookies (enabled by default)
#COOKIES_ENABLED = False

# Disable Telnet Console (enabled by default)
#TELNETCONSOLE_ENABLED = False

# Override the default request headers:
#DEFAULT_REQUEST_HEADERS = {
#   'Accept': 'text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8',
#   'Accept-Language': 'en',
#}

# Enable or disable spider middlewares
# See https://doc.scrapy.org/en/latest/topics/spider-middleware.html
#SPIDER_MIDDLEWARES = {
#    'wangyiPro.middlewares.WangyiproSpiderMiddleware': 543,
#}

# Enable or disable downloader middlewares
# See https://doc.scrapy.org/en/latest/topics/downloader-middleware.html
DOWNLOADER_MIDDLEWARES = {
   'wangyiPro.middlewares.WangyiproDownloaderMiddleware': 543,
   'wangyiPro.middlewares.RandomUserAgent': 542,
   'wangyiPro.middlewares.Proxy': 541,
}

# Enable or disable extensions
# See https://doc.scrapy.org/en/latest/topics/extensions.html
#EXTENSIONS = {
#    'scrapy.extensions.telnet.TelnetConsole': None,
#}

# Configure item pipelines
# See https://doc.scrapy.org/en/latest/topics/item-pipeline.html
ITEM_PIPELINES = {
   'wangyiPro.pipelines.WangyiproPipeline': 300,
}

# Enable and configure the AutoThrottle extension (disabled by default)
# See https://doc.scrapy.org/en/latest/topics/autothrottle.html
#AUTOTHROTTLE_ENABLED = True
# The initial download delay
#AUTOTHROTTLE_START_DELAY = 5
# The maximum download delay to be set in case of high latencies
#AUTOTHROTTLE_MAX_DELAY = 60
# The average number of requests Scrapy should be sending in parallel to
# each remote server
#AUTOTHROTTLE_TARGET_CONCURRENCY = 1.0
# Enable showing throttling stats for every response received:
#AUTOTHROTTLE_DEBUG = False

# Enable and configure HTTP caching (disabled by default)
# See https://doc.scrapy.org/en/latest/topics/downloader-middleware.html#httpcache-middleware-settings
#HTTPCACHE_ENABLED = True
#HTTPCACHE_EXPIRATION_SECS = 0
#HTTPCACHE_DIR = 'httpcache'
#HTTPCACHE_IGNORE_HTTP_CODES = []
#HTTPCACHE_STORAGE = 'scrapy.extensions.httpcache.FilesystemCacheStorage'

 

05-基于RedisSpider类实现的分布式爬虫

a)代码修改（爬虫类）：
    i.导包：
　　　　from scrapy_redis.spiders import RedisSpider
    ii.将爬虫类的父类修改成RedisSpider
    iii.将起始url列表注释，添加一个redis_key（调度器队列的名称）的属性
    　　redis_key = ‘wangyi’
b)redis数据库配置文件的配置redisxxx.conf：
    i.#bind 127.0.0.1
    ii.protected-mode no
c)对项目中settings进行配置:
REDIS_HOST = 'redis服务的ip地址'
REDIS_PORT = 6379
REDIS_ENCODING = ‘utf-8’
REDIS_PARAMS = {‘password’:’123456’}
# 使用scrapy-redis组件的去重队列
DUPEFILTER_CLASS = "scrapy_redis.dupefilter.RFPDupeFilter"
# 使用scrapy-redis组件自己的调度器
SCHEDULER = "scrapy_redis.scheduler.Scheduler"
# 是否允许暂停
SCHEDULER_PERSIST = True

# 使用scrapy-redis组件中封装好的管道
ITEM_PIPELINES = {
   'scrapy_redis.pipelines.RedisPipeline': 400,
}

d)开启redis数据库的服务：redis-server 配置文件
e)执行爬虫文件：在spiders文件夹下
　　scrapy runspider wangyi.py
f)向调度器的队列中扔一个起始url：
　　i.开启redis客户端: redis-cli
　　ii.向调度器队列中扔一个起始url
   　　lpush wangyi https://news.163.com

# -*- coding: utf-8 -*-
import scrapy
from selenium import webdriver
from wangyiPro.items import WangyiproItem
from scrapy_redis.spiders import RedisSpider


class WangyiSpider(RedisSpider):
    name = 'wangyi'
    # allowed_domains = ['https://news.163.com']
    # start_urls = ['https://news.163.com/']

    redis_key = 'wangyi'

    def __init__(self):
        # 实例化一个浏览器对象
        self.bro = webdriver.Chrome(executable_path='/Users/huangyanpeng/Desktop/scrapy框架/firstScrapy/wangyiPro/chromedriver 2')

    # 必须在整个爬虫结束后，关闭浏览器
    def closed(self, spider):
        print("爬虫结束！")
        self.bro.quit()

    def parse(self, response):
        lis = response.xpath('//div[@class="ns_area list"]/ul/li')
        indexs = [3, 4, 6, 7]
        # 存储的是 国内，国际，军事，航空 四个板块对应的li标签对象
        li_list = []
        for index in indexs:
            li_list.append(lis[index])
        # 获取四个板块的链接和文字标题
        for li in li_list:
            url = li.xpath('./a/@href').extract_first()
            title = li.xpath('./a/text()').extract_first()

            # print(title, url)
            # 对每一个板块对应的url发起请求，获取页面数据（标题，缩略图，关键字，发布时间，标题的url）
            yield scrapy.Request(url=url, callback=self.parseSecond, meta={'title': title, 'url': url})

    def parseSecond(self, response):
        div_list = response.xpath('//div[@class="data_row news_article clearfix "]')
        # print(len(div_list))
        for div in div_list:
            head = div.xpath('.//div[@class="news_title"]/h3/a/text()').extract_first()
            url = div.xpath('.//div[@class="news_title"]/h3/a/@href').extract_first()
            imgUrl = div.xpath('./a/img/@src').extract_first()
            tag = div.xpath('.//div[@class="news_tag"]//text()').extract()
            tags = []
            for t in tag:
                t = t.strip(' 
 	')
                tags.append(t)
            tag = "".join(tags)

            # 获取meta传递过来的数据值title
            title = response.meta['title']

            # 实例化item对象，将解析到的数据值存储到item对象中
            item = WangyiproItem()
            item['head'] = head
            item['url'] = url
            item['imgUrl'] = imgUrl
            item['tag'] = tag
            item['title'] = title

            # 对url发起请求，获取对应页面中存储的新闻内容数据
            yield scrapy.Request(url=url, callback=self.getContent, meta={'item': item})
            print(head+":"+url+":"+imgUrl+":"+tag)

    def getContent(self, response):
        # 获取传递过来的item
        item = response.meta['item']

        # 解析当前页面中存储的新闻数据
        content_list = response.xpath('//div[@class="post_text"]/p/text()').extract()
        content = "".join(content_list)
        item['content'] = content

        yield item

# -*- coding: utf-8 -*-

# Define here the models for your scraped items
#
# See documentation in:
# https://doc.scrapy.org/en/latest/topics/items.html

import scrapy


class WangyiproItem(scrapy.Item):
    # define the fields for your item here like:
    head = scrapy.Field()
    url = scrapy.Field()
    imgUrl = scrapy.Field()
    tag = scrapy.Field()
    title = scrapy.Field()
    content = scrapy.Field()

# -*- 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.http import HtmlResponse
import time

'''
UA池
'''
# 导包
from scrapy.contrib.downloadermiddleware.useragent import UserAgentMiddleware
import random
# UA池代码的编写（单独给UA池封装一个下载中间件的一个类）


class RandomUserAgent(UserAgentMiddleware):

    def process_request(self, request, spider):
        # 从列表中随机抽选出一个ua值
        ua = random.choice(user_agent_list)
        # ua值进行当前拦截到请求的ua的写入操作
        request.headers.setdefault('User-Agent',ua)


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"
]


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.

    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

    # 可以拦截到响应对象(下载器传递给spider的响应对象)
    # request：响应对象对应的请求对象
    # response：拦截到的响应对象
    # spider：爬虫文件中对应的爬虫类的实例
    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

        # 响应对象中存储页面数据的篡改
        # print(request.url)
        if request.url in ['http://news.163.com/domestic/', 'http://news.163.com/air/', 'http://war.163.com/', 'http://news.163.com/world/']:
            spider.bro.get(url=request.url)

            js = 'windows.scrollTo(0, document.body.scrollHeight)'
            spider.bro.execute_script(js)
            # 一定要给浏览器移动的缓冲加载数据的时间
            time.sleep(2)
            # page_text 包含了动态加载出来的页面数据
            page_text = spider.bro.page_source
            # current_url属性 表示 刚才浏览器发起请求所对应的url
            # body: 表示 响应对象所携带的数据值
            return HtmlResponse(url=spider.bro.current_url, body=page_text, encoding='utf-8', request=request)
        else:
            return response


'''
代理池
'''
# 批量对拦截到的请求进行ip更换
# 单独封装下载中间件类


class Proxy(object):
    def process_request(self, request, spider):
        # 对拦截到请求的url进行判断（协议头到底是http还是https）
        # request.url返回值：http://www.xxx.com
        h = request.url.split(':')[0]  # 请求的协议头
        if h == 'https':
            ip = random.choice(PROXY_https)
            request.meta['proxy'] = 'https://'+ip
        else:
            ip = random.choice(PROXY_http)
            request.meta['proxy'] = 'http://' + ip

# 可被选用的代理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',
]

# -*- coding: utf-8 -*-

# Scrapy settings for wangyiPro project
#
# For simplicity, this file contains only settings considered important or
# commonly used. You can find more settings consulting the documentation:
#
#     https://doc.scrapy.org/en/latest/topics/settings.html
#     https://doc.scrapy.org/en/latest/topics/downloader-middleware.html
#     https://doc.scrapy.org/en/latest/topics/spider-middleware.html

BOT_NAME = 'wangyiPro'

SPIDER_MODULES = ['wangyiPro.spiders']
NEWSPIDER_MODULE = 'wangyiPro.spiders'


# Crawl responsibly by identifying yourself (and your website) on the user-agent
# USER_AGENT = 'wangyiPro (+http://www.yourdomain.com)'
USER_AGENT = "Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/67.0.3396.87 Safari/537.36"

# Obey robots.txt rules
ROBOTSTXT_OBEY = False

# Configure maximum concurrent requests performed by Scrapy (default: 16)
# CONCURRENT_REQUESTS = 32

# Configure a delay for requests for the same website (default: 0)
# See https://doc.scrapy.org/en/latest/topics/settings.html#download-delay
# See also autothrottle settings and docs
#DOWNLOAD_DELAY = 3
# The download delay setting will honor only one of:
#CONCURRENT_REQUESTS_PER_DOMAIN = 16
#CONCURRENT_REQUESTS_PER_IP = 16

# Disable cookies (enabled by default)
#COOKIES_ENABLED = False

# Disable Telnet Console (enabled by default)
#TELNETCONSOLE_ENABLED = False

# Override the default request headers:
#DEFAULT_REQUEST_HEADERS = {
#   'Accept': 'text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8',
#   'Accept-Language': 'en',
#}

# Enable or disable spider middlewares
# See https://doc.scrapy.org/en/latest/topics/spider-middleware.html
#SPIDER_MIDDLEWARES = {
#    'wangyiPro.middlewares.WangyiproSpiderMiddleware': 543,
#}

# Enable or disable downloader middlewares
# See https://doc.scrapy.org/en/latest/topics/downloader-middleware.html
DOWNLOADER_MIDDLEWARES = {
   'wangyiPro.middlewares.WangyiproDownloaderMiddleware': 543,
   'wangyiPro.middlewares.RandomUserAgent': 542,
   'wangyiPro.middlewares.Proxy': 541,
}

# Enable or disable extensions
# See https://doc.scrapy.org/en/latest/topics/extensions.html
#EXTENSIONS = {
#    'scrapy.extensions.telnet.TelnetConsole': None,
#}

# Configure item pipelines
# See https://doc.scrapy.org/en/latest/topics/item-pipeline.html
ITEM_PIPELINES = {
   # 'wangyiPro.pipelines.WangyiproPipeline': 300,
   'scrapy_redis.pipelines.RedisPipeline': 400,

}

# Enable and configure the AutoThrottle extension (disabled by default)
# See https://doc.scrapy.org/en/latest/topics/autothrottle.html
#AUTOTHROTTLE_ENABLED = True
# The initial download delay
#AUTOTHROTTLE_START_DELAY = 5
# The maximum download delay to be set in case of high latencies
#AUTOTHROTTLE_MAX_DELAY = 60
# The average number of requests Scrapy should be sending in parallel to
# each remote server
#AUTOTHROTTLE_TARGET_CONCURRENCY = 1.0
# Enable showing throttling stats for every response received:
#AUTOTHROTTLE_DEBUG = False

# Enable and configure HTTP caching (disabled by default)
# See https://doc.scrapy.org/en/latest/topics/downloader-middleware.html#httpcache-middleware-settings
#HTTPCACHE_ENABLED = True
#HTTPCACHE_EXPIRATION_SECS = 0
#HTTPCACHE_DIR = 'httpcache'
#HTTPCACHE_IGNORE_HTTP_CODES = []
#HTTPCACHE_STORAGE = 'scrapy.extensions.httpcache.FilesystemCacheStorage'

# REDIS_HOST = '127.0.0.1'
REDIS_PORT = 6379
REDIS_ENCODING = 'utf-8'
# REDIS_PARAMS = {'password': '123456'}


# 使用scrapy-redis组件的去重队列
DUPEFILTER_CLASS = "scrapy_redis.dupefilter.RFPDupeFilter"
# 使用scrapy-redis组件自己的调度器
SCHEDULER = "scrapy_redis.scheduler.Scheduler"
# 是否允许暂停
SCHEDULER_PERSIST = True