Scrapy的补充
windows编码
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import sys,os sys.stdout=io.TextIOWrapper(sys.stdout.buffer,encoding='gb18030')
数据拼接
from urllib.parse import urlencode v = { 'k1':'v1', 'k2':'v2' } result = urlencode(v) print(result)
结果
k1=v1&k2=v2
URL的唯一标识
from scrapy.utils.request import request_fingerprint from scrapy.http import Request url1 = "http://www.luffycity.com?k1=123&k2=456" req1 = Request(url=url1) url2 = "http://www.luffycity.com?k2=456&k1=123" req2 = Request(url=url2) fd1 = request_fingerprint(request=req1) fd2 = request_fingerprint(request=req2) print(fd1) print(fd2) 结果: 500b31c7eed3dee70088a2dcf6c0906713e9d428 500b31c7eed3dee70088a2dcf6c0906713e9d428
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""" """ # 原来 """ import requests url_list = ['http://www.baidu.com', 'http://www.baidu.com', 'http://www.baidu.com', ] for item in url_list: response = requests.get(item) print(response.text) """ # 现在 """ 非阻塞,不等待; 我向贝贝、高件套、小东北发起连接请求时候,不等连接再去连下一个,而是发送一个只会,马上发送下一个。 import socket sk = socket.socket() sk.setblocking(False) sk.connect((1.1.1.1,80)) import socket sk = socket.socket() sk.setblocking(False) sk.connect((1.1.1.2,80)) import socket sk = socket.socket() sk.setblocking(False) sk.connect((1.1.1.3,80)) 异步,回调; 我帮助龙泰、呼呼、刘淞找到想要的人只会,我会主动通知他们。 def callback(contents): print(contents) 事件循环; 我,我一直在循环三个socket任务(即:贝贝、高件套、小东北),检查他三个状态:是否连接成功;是否返回结果。 总结: 官方:基于事件循环的异步非阻塞模块。 白话:一个线程同时可以向多个目标发起Http请求。 """ from twisted.web.client import getPage, defer from twisted.internet import reactor # 第一部分:代理开始接收任务 def callback(contents): print(contents) deferred_list = [] # [(龙泰,贝贝),(刘淞,宝件套),(呼呼,东北)] url_list = ['http://www.bing.com', 'https://segmentfault.com/','https://stackoverflow.com/' ] for url in url_list: deferred = getPage(bytes(url, encoding='utf8')) # (我,要谁) deferred.addCallback(callback) deferred_list.append(deferred) # # 第二部分:代理执行完任务后,停止 dlist = defer.DeferredList(deferred_list) def all_done(arg): reactor.stop() dlist.addBoth(all_done) # 第三部分:代理开始去处理吧 reactor.run()
数据封装
class Request(object): def __init__(self,url,callback): self.url = url self.callback = callback Request(url='hxfasdfasdfasdf',callback=lambda x:x )
去重规则
scrapy默认使用 scrapy.dupefilter.RFPDupeFilter 进行去重,相关配置有:
DUPEFILTER_CLASS = 'scrapy.dupefilter.RFPDupeFilter' DUPEFILTER_DEBUG = False JOBDIR = "保存范文记录的日志路径,如:/root/" # 最终路径为 /root/requests.seen
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from scrapy.dupefilter import BaseDupeFilter from scrapy.utils.request import request_fingerprint class XdbDupeFilter(BaseDupeFilter): def __init__(self): self.visited_fd = set() @classmethod def from_settings(cls, settings): return cls() def request_seen(self, request): fd = request_fingerprint(request=request) if fd in self.visited_fd: return True self.visited_fd.add(fd) def open(self): # can return deferred print('开始') def close(self, reason): # can return a deferred print('结束') # def log(self, request, spider): # log that a request has been filtered # print('日志')
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# 修改默认的去重规则 # DUPEFILTER_CLASS = 'scrapy.dupefilter.RFPDupeFilter' DUPEFILTER_CLASS = 'xdb.dupefiltexrs.XdbDupeFilter'
# -*- coding: utf-8 -*- import scrapy from scrapy.http.response.html import HtmlResponse # import sys,os,io # sys.stdout=io.TextIOWrapper(sys.stdout.buffer,encoding='gb18030') from xdb.items import XdbItem import scrapy from scrapy.http.cookies import CookieJar from scrapy.http import Request from urllib.parse import urlencode class ChoutiSpider(scrapy.Spider): name = 'chouti' allowed_domains = ['chouti.com'] start_urls = ['https://dig.chouti.com/'] cookie_dict = {} def parse(self, response): """ 第一次访问抽屉返回的内容:response :param response: :return: """ # 去响应头中获取cookie # 去响应头中获取cookie,cookie保存在cookie_jar对象 cookie_jar = CookieJar() cookie_jar.extract_cookies(response, response.request) # 去对象中将cookie解析到字典 for k, v in cookie_jar._cookies.items(): for i, j in v.items(): for m, n in j.items(): self.cookie_dict[m] = n.value yield Request( url='https://dig.chouti.com/login', method='POST', body="phone=8613121758648&password=woshiniba&oneMonth=1",# # body=urlencode({})"phone=8615131255555&password=12sdf32sdf&oneMonth=1" cookies=self.cookie_dict, headers={ 'Content-Type': 'application/x-www-form-urlencoded; charset=UTF-8' }, callback=self.c
cookie处理
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# -*- coding: utf-8 -*- import scrapy from scrapy.http.response.html import HtmlResponse # import sys,os,io # sys.stdout=io.TextIOWrapper(sys.stdout.buffer,encoding='gb18030') from xdb.items import XdbItem import scrapy from scrapy.http.cookies import CookieJar from scrapy.http import Request from urllib.parse import urlencode class ChoutiSpider(scrapy.Spider): name = 'chouti' allowed_domains = ['chouti.com'] start_urls = ['https://dig.chouti.com/'] cookie_dict = {} def parse(self, response): """ 第一次访问抽屉返回的内容:response :param response: :return: """ # 去响应头中获取cookie # 去响应头中获取cookie,cookie保存在cookie_jar对象 cookie_jar = CookieJar() cookie_jar.extract_cookies(response, response.request) # 去对象中将cookie解析到字典 for k, v in cookie_jar._cookies.items(): for i, j in v.items(): for m, n in j.items(): self.cookie_dict[m] = n.value yield Request( url='https://dig.chouti.com/login', method='POST', body="phone=8613121758648&password=woshiniba&oneMonth=1",# # body=urlencode({})"phone=8615131255555&password=12sdf32sdf&oneMonth=1" cookies=self.cookie_dict, headers={ 'Content-Type': 'application/x-www-form-urlencoded; charset=UTF-8' }, callback=self.check_login
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yield Request( url='https://dig.chouti.com/login', method='POST', body="phone=861300000000&password=12345678&oneMonth=1",# cookies=self.cookie_dict, headers={ 'Content-Type': 'application/x-www-form-urlencoded; charset=UTF-8' }, callback=self.check_login )
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自动:****meta={'cookiejar': True}***** # class ChoutiSpider(scrapy.Spider): # name = 'chouti' # allowed_domains = ['chouti.com'] # start_urls = ['http://dig.chouti.com/',] # # def start_requests(self): # for url in self.start_urls: # yield Request(url=url,callback=self.parse_index,meta={'cookiejar':True}) # # def parse_index(self,response): # req = Request( # url='http://dig.chouti.com/login', # method='POST', # headers={'Content-Type': 'application/x-www-form-urlencoded; charset=UTF-8'}, # body='phone=8613121758648&password=woshiniba&oneMonth=1', # callback=self.parse_check_login, # meta={'cookiejar': True} # ) # yield req # # def parse_check_login(self,response): # # print(response.text) # yield Request( # url='https://dig.chouti.com/link/vote?linksId=19440976', # method='POST', # callback=self.parse_show_result, # meta={'cookiejar': True} # ) # # def parse_show_result(self,response): # print(response.text)
代理
内置代理和自定义代理
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方式一 #def start_requests(self): # os.environ['HTTP_PROXY'] = "http://root:woshiniba//192.168.11.11" # os.environ['HTTPS _PROXY'] = "http://192.168.11.11" 方式二 # for url in self.start_urls: # yield Request(url=url,callback=self.parse,meta={ ‘proxy’:"http://root:woshiniba//192.168.11.11" }) meta中的代理优先
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# by luffycity.com import base64 import random from six.moves.urllib.parse import unquote try: from urllib2 import _parse_proxy except ImportError: from urllib.request import _parse_proxy from six.moves.urllib.parse import urlunparse from scrapy.utils.python import to_bytes class XdbProxyMiddleware(object): def _basic_auth_header(self, username, password): user_pass = to_bytes( '%s:%s' % (unquote(username), unquote(password)), encoding='latin-1') return base64.b64encode(user_pass).strip() def process_request(self, request, spider): PROXIES = [ "http://root:woshiniba@192.168.11.11:9999/", "http://root:woshiniba@192.168.11.12:9999/", "http://root:woshiniba@192.168.11.13:9999/", "http://root:woshiniba@192.168.11.14:9999/", "http://root:woshiniba@192.168.11.15:9999/", "http://root:woshiniba@192.168.11.16:9999/", ] url = random.choice(PROXIES) orig_type = "" proxy_type, user, password, hostport = _parse_proxy(url) proxy_url = urlunparse((proxy_type or orig_type, hostport, '', '', '', '')) if user: creds = self._basic_auth_header(user, password) else: creds = None request.meta['proxy'] = proxy_url if creds: request.headers['Proxy-Authorization'] = b'Basic ' + creds class DdbProxyMiddleware(object): def process_request(self, request, spider): PROXIES = [ {'ip_port': '111.11.228.75:80', 'user_pass': ''}, {'ip_port': '120.198.243.22:80', 'user_pass': ''}, {'ip_port': '111.8.60.9:8123', 'user_pass': ''}, {'ip_port': '101.71.27.120:80', 'user_pass': ''}, {'ip_port': '122.96.59.104:80', 'user_pass': ''}, {'ip_port': '122.224.249.122:8088', 'user_pass': ''}, ] proxy = random.choice(PROXIES) if proxy['user_pass'] is not None: request.meta['proxy'] = to_bytes("http://%s" % proxy['ip_port']) encoded_user_pass = base64.b64encode(to_bytes(proxy['user_pass'])) request.headers['Proxy-Authorization'] = to_bytes('Basic ' + encoded_user_pass) else: request.meta['proxy'] = to_bytes("http://%s" % proxy['ip_port'])
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DOWNLOADER_MIDDLEWARES = { #'xdb.middlewares.XdbDownloaderMiddleware': 543, 'xdb.proxy.XdbProxyMiddleware':751, }
中间件
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class DownMiddleware1(object): def process_request(self, request, spider): """ 请求需要被下载时,经过所有下载器中间件的process_request调用 :param request: :param spider: :return: None,继续后续中间件去下载; Response对象,停止process_request的执行,开始执行process_response Request对象,停止中间件的执行,将Request重新调度器 raise IgnoreRequest异常,停止process_request的执行,开始执行process_exception """ pass def process_response(self, request, response, spider): """ spider处理完成,返回时调用 :param response: :param result: :param spider: :return: Response 对象:转交给其他中间件process_response Request 对象:停止中间件,request会被重新调度下载 raise IgnoreRequest 异常:调用Request.errback """ print('response1') return response def process_exception(self, request, exception, spider): """ 当下载处理器(download handler)或 process_request() (下载中间件)抛出异常 :param response: :param exception: :param spider: :return: None:继续交给后续中间件处理异常; Response对象:停止后续process_exception方法 Request对象:停止中间件,request将会被重新调用下载 """ return None 下载器中间件
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class SpiderMiddleware(object): def process_spider_input(self,response, spider): """ 下载完成,执行,然后交给parse处理 :param response: :param spider: :return: """ pass def process_spider_output(self,response, result, spider): """ spider处理完成,返回时调用 :param response: :param result: :param spider: :return: 必须返回包含 Request 或 Item 对象的可迭代对象(iterable) """ return result def process_spider_exception(self,response, exception, spider): """ 异常调用 :param response: :param exception: :param spider: :return: None,继续交给后续中间件处理异常;含 Response 或 Item 的可迭代对象(iterable),交给调度器或pipeline """ return None def process_start_requests(self,start_requests, spider): """ 爬虫启动时调用 :param start_requests: :param spider: :return: 包含 Request 对象的可迭代对象 """ return start_requests 爬虫中间件
下载中间件在每次下载前和下载后对请求和响应可以定制功能,爬虫中间件主要功能是在爬虫运行过程中进行一些处理.
自定义代理使用的就是下载中间件
Downloader Middleware有以下几个函数被管理
- process_request request通过下载中间件时,该方法被调用
- process_response 下载结果经过中间件时被此方法处理
- process_exception 下载过程中出现异常时被调用
编写中间件时,需要思考要实现的功能最适合在那个过程处理,就编写哪个方法.
中间件可以用来处理请求,处理结果或者结合信号协调一些方法的使用等.也可以在原有的爬虫上添加适应项目的其他功能,这一点在扩展中编写也可以达到目的,实际上扩展更加去耦合化,推荐使用扩展.
Spider Middleware有以下几个函数被管理:
- process_spider_input 接收一个response对象并处理,
位置是Downloader-->process_spider_input-->Spiders(Downloader和Spiders是scrapy官方结构图中的组件)
- process_spider_exception spider出现的异常时被调用
- process_spider_output 当Spider处理response返回result时,该方法被调用
- process_start_requests 当spider发出请求时,被调用
位置是Spiders-->process_start_requests-->Scrapy Engine(Scrapy Engine是scrapy官方结构图中的组件)
代码示例
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from scrapy.http import HtmlResponse from scrapy.http import Request class Md1(object): @classmethod def from_crawler(cls, crawler): # This method is used by Scrapy to create your spiders. s = cls() 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 print('md1.process_request',request) # 1. 返回Response # import requests # result = requests.get(request.url) # return HtmlResponse(url=request.url, status=200, headers=None, body=result.content) # 2. 返回Request # return Request('https://dig.chouti.com/r/tec/hot/1') # 3. 抛出异常 # from scrapy.exceptions import IgnoreRequest # raise IgnoreRequest # 4. 对请求进行加工(*) # request.headers['user-agent'] = "Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/63.0.3239.132 Safari/537.36" 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 print('m1.process_response',request,response) return response 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
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DOWNLOADER_MIDDLEWARES = { #'xdb.middlewares.XdbDownloaderMiddleware': 543, # 'xdb.proxy.XdbProxyMiddleware':751, 'xdb.md.Md1':666, 'xdb.md.Md2':667
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class Sd1(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() 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 # 只在爬虫启动时,执行一次。 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
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SPIDER_MIDDLEWARES = { # 'xdb.middlewares.XdbSpiderMiddleware': 543, 'xdb.sd.Sd1': 666, 'xdb.sd.Sd2': 667, }
定制请求 简化运行命令,一次执行所有爬虫程序
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import sys from scrapy.cmdline import execute if __name__ == '__main__': execute(["scrapy",“crawl“,"chouti","--nolog"])
多个爬虫文件
- 在spiders同级创建任意目录,如:commands
- 在其中创建 crawlall.py 文件 (此处文件名就是自定义的命令)
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from scrapy.commands import ScrapyCommand from scrapy.utils.project import get_project_settings class Command(ScrapyCommand): requires_project = True def syntax(self): return '[options]' def short_desc(self): return 'Runs all of the spiders' def run(self, args, opts): spider_list = self.crawler_process.spiders.list() for name in spider_list: self.crawler_process.crawl(name, **opts.__dict__) self.crawler_process.start() crawlall.py
- 在settings.py 中添加配置 COMMANDS_MODULE = '项目名称.目录名称'
- 在项目目录执行命令:scrapy crawlall
其他
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# -*- coding: utf-8 -*- # Scrapy settings for step8_king project # # For simplicity, this file contains only settings considered important or # commonly used. You can find more settings consulting the documentation: # # http://doc.scrapy.org/en/latest/topics/settings.html # http://scrapy.readthedocs.org/en/latest/topics/downloader-middleware.html # http://scrapy.readthedocs.org/en/latest/topics/spider-middleware.html # 1. 爬虫名称 BOT_NAME = 'step8_king' # 2. 爬虫应用路径 SPIDER_MODULES = ['step8_king.spiders'] NEWSPIDER_MODULE = 'step8_king.spiders' # Crawl responsibly by identifying yourself (and your website) on the user-agent # 3. 客户端 user-agent请求头 # USER_AGENT = 'step8_king (+http://www.yourdomain.com)' # Obey robots.txt rules # 4. 禁止爬虫配置 # ROBOTSTXT_OBEY = False # Configure maximum concurrent requests performed by Scrapy (default: 16) # 5. 并发请求数 # CONCURRENT_REQUESTS = 4 # Configure a delay for requests for the same website (default: 0) # See http://scrapy.readthedocs.org/en/latest/topics/settings.html#download-delay # See also autothrottle settings and docs # 6. 延迟下载秒数 # DOWNLOAD_DELAY = 2 # The download delay setting will honor only one of: # 7. 单域名访问并发数,并且延迟下次秒数也应用在每个域名 # CONCURRENT_REQUESTS_PER_DOMAIN = 2 # 单IP访问并发数,如果有值则忽略:CONCURRENT_REQUESTS_PER_DOMAIN,并且延迟下次秒数也应用在每个IP # CONCURRENT_REQUESTS_PER_IP = 3 # Disable cookies (enabled by default) # 8. 是否支持cookie,cookiejar进行操作cookie # COOKIES_ENABLED = True # COOKIES_DEBUG = True # Disable Telnet Console (enabled by default) # 9. Telnet用于查看当前爬虫的信息,操作爬虫等... # 使用telnet ip port ,然后通过命令操作 # TELNETCONSOLE_ENABLED = True # TELNETCONSOLE_HOST = '127.0.0.1' # TELNETCONSOLE_PORT = [6023,] # 10. 默认请求头 # 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', # } # Configure item pipelines # See http://scrapy.readthedocs.org/en/latest/topics/item-pipeline.html # 11. 定义pipeline处理请求 # ITEM_PIPELINES = { # 'step8_king.pipelines.JsonPipeline': 700, # 'step8_king.pipelines.FilePipeline': 500, # } # 12. 自定义扩展,基于信号进行调用 # Enable or disable extensions # See http://scrapy.readthedocs.org/en/latest/topics/extensions.html # EXTENSIONS = { # # 'step8_king.extensions.MyExtension': 500, # } # 13. 爬虫允许的最大深度,可以通过meta查看当前深度;0表示无深度 # DEPTH_LIMIT = 3 # 14. 爬取时,0表示深度优先Lifo(默认);1表示广度优先FiFo # 后进先出,深度优先 # DEPTH_PRIORITY = 0 # SCHEDULER_DISK_QUEUE = 'scrapy.squeue.PickleLifoDiskQueue' # SCHEDULER_MEMORY_QUEUE = 'scrapy.squeue.LifoMemoryQueue' # 先进先出,广度优先 # DEPTH_PRIORITY = 1 # SCHEDULER_DISK_QUEUE = 'scrapy.squeue.PickleFifoDiskQueue' # SCHEDULER_MEMORY_QUEUE = 'scrapy.squeue.FifoMemoryQueue' # 15. 调度器队列 # SCHEDULER = 'scrapy.core.scheduler.Scheduler' # from scrapy.core.scheduler import Scheduler # 16. 访问URL去重 # DUPEFILTER_CLASS = 'step8_king.duplication.RepeatUrl' # Enable and configure the AutoThrottle extension (disabled by default) # See http://doc.scrapy.org/en/latest/topics/autothrottle.html """ 17. 自动限速算法 from scrapy.contrib.throttle import AutoThrottle 自动限速设置 1. 获取最小延迟 DOWNLOAD_DELAY 2. 获取最大延迟 AUTOTHROTTLE_MAX_DELAY 3. 设置初始下载延迟 AUTOTHROTTLE_START_DELAY 4. 当请求下载完成后,获取其"连接"时间 latency,即:请求连接到接受到响应头之间的时间 5. 用于计算的... AUTOTHROTTLE_TARGET_CONCURRENCY target_delay = latency / self.target_concurrency new_delay = (slot.delay + target_delay) / 2.0 # 表示上一次的延迟时间 new_delay = max(target_delay, new_delay) new_delay = min(max(self.mindelay, new_delay), self.maxdelay) slot.delay = new_delay """ # 开始自动限速 # AUTOTHROTTLE_ENABLED = True # The initial download delay # 初始下载延迟 # AUTOTHROTTLE_START_DELAY = 5 # The maximum download delay to be set in case of high latencies # 最大下载延迟 # AUTOTHROTTLE_MAX_DELAY = 10 # The average number of requests Scrapy should be sending in parallel to each remote server # 平均每秒并发数 # AUTOTHROTTLE_TARGET_CONCURRENCY = 1.0 # Enable showing throttling stats for every response received: # 是否显示 # AUTOTHROTTLE_DEBUG = True # Enable and configure HTTP caching (disabled by default) # See http://scrapy.readthedocs.org/en/latest/topics/downloader-middleware.html#httpcache-middleware-settings """ 18. 启用缓存 目的用于将已经发送的请求或相应缓存下来,以便以后使用 from scrapy.downloadermiddlewares.httpcache import HttpCacheMiddleware from scrapy.extensions.httpcache import DummyPolicy from scrapy.extensions.httpcache import FilesystemCacheStorage """ # 是否启用缓存策略 # HTTPCACHE_ENABLED = True # 缓存策略:所有请求均缓存,下次在请求直接访问原来的缓存即可 # HTTPCACHE_POLICY = "scrapy.extensions.httpcache.DummyPolicy" # 缓存策略:根据Http响应头:Cache-Control、Last-Modified 等进行缓存的策略 # HTTPCACHE_POLICY = "scrapy.extensions.httpcache.RFC2616Policy" # 缓存超时时间 # HTTPCACHE_EXPIRATION_SECS = 0 # 缓存保存路径 # HTTPCACHE_DIR = 'httpcache' # 缓存忽略的Http状态码 # HTTPCACHE_IGNORE_HTTP_CODES = [] # 缓存存储的插件 # HTTPCACHE_STORAGE = 'scrapy.extensions.httpcache.FilesystemCacheStorage' """ 19. 代理,需要在环境变量中设置 from scrapy.contrib.downloadermiddleware.httpproxy import HttpProxyMiddleware 方式一:使用默认 os.environ { http_proxy:http://root:woshiniba@192.168.11.11:9999/ https_proxy:http://192.168.11.11:9999/ } 方式二:使用自定义下载中间件 def to_bytes(text, encoding=None, errors='strict'): if isinstance(text, bytes): return text if not isinstance(text, six.string_types): raise TypeError('to_bytes must receive a unicode, str or bytes ' 'object, got %s' % type(text).__name__) if encoding is None: encoding = 'utf-8' return text.encode(encoding, errors) class ProxyMiddleware(object): def process_request(self, request, spider): PROXIES = [ {'ip_port': '111.11.228.75:80', 'user_pass': ''}, {'ip_port': '120.198.243.22:80', 'user_pass': ''}, {'ip_port': '111.8.60.9:8123', 'user_pass': ''}, {'ip_port': '101.71.27.120:80', 'user_pass': ''}, {'ip_port': '122.96.59.104:80', 'user_pass': ''}, {'ip_port': '122.224.249.122:8088', 'user_pass': ''}, ] proxy = random.choice(PROXIES) if proxy['user_pass'] is not None: request.meta['proxy'] = to_bytes("http://%s" % proxy['ip_port']) encoded_user_pass = base64.encodestring(to_bytes(proxy['user_pass'])) request.headers['Proxy-Authorization'] = to_bytes('Basic ' + encoded_user_pass) print "**************ProxyMiddleware have pass************" + proxy['ip_port'] else: print "**************ProxyMiddleware no pass************" + proxy['ip_port'] request.meta['proxy'] = to_bytes("http://%s" % proxy['ip_port']) DOWNLOADER_MIDDLEWARES = { 'step8_king.middlewares.ProxyMiddleware': 500, } """ """ 20. Https访问 Https访问时有两种情况: 1. 要爬取网站使用的可信任证书(默认支持) DOWNLOADER_HTTPCLIENTFACTORY = "scrapy.core.downloader.webclient.ScrapyHTTPClientFactory" DOWNLOADER_CLIENTCONTEXTFACTORY = "scrapy.core.downloader.contextfactory.ScrapyClientContextFactory" 2. 要爬取网站使用的自定义证书 DOWNLOADER_HTTPCLIENTFACTORY = "scrapy.core.downloader.webclient.ScrapyHTTPClientFactory" DOWNLOADER_CLIENTCONTEXTFACTORY = "step8_king.https.MySSLFactory" # https.py from scrapy.core.downloader.contextfactory import ScrapyClientContextFactory from twisted.internet.ssl import (optionsForClientTLS, CertificateOptions, PrivateCertificate) class MySSLFactory(ScrapyClientContextFactory): def getCertificateOptions(self): from OpenSSL import crypto v1 = crypto.load_privatekey(crypto.FILETYPE_PEM, open('/Users/wupeiqi/client.key.unsecure', mode='r').read()) v2 = crypto.load_certificate(crypto.FILETYPE_PEM, open('/Users/wupeiqi/client.pem', mode='r').read()) return CertificateOptions( privateKey=v1, # pKey对象 certificate=v2, # X509对象 verify=False, method=getattr(self, 'method', getattr(self, '_ssl_method', None)) ) 其他: 相关类 scrapy.core.downloader.handlers.http.HttpDownloadHandler scrapy.core.downloader.webclient.ScrapyHTTPClientFactory scrapy.core.downloader.contextfactory.ScrapyClientContextFactory 相关配置 DOWNLOADER_HTTPCLIENTFACTORY DOWNLOADER_CLIENTCONTEXTFACTORY """ """ 21. 爬虫中间件 class SpiderMiddleware(object): def process_spider_input(self,response, spider): ''' 下载完成,执行,然后交给parse处理 :param response: :param spider: :return: ''' pass def process_spider_output(self,response, result, spider): ''' spider处理完成,返回时调用 :param response: :param result: :param spider: :return: 必须返回包含 Request 或 Item 对象的可迭代对象(iterable) ''' return result def process_spider_exception(self,response, exception, spider): ''' 异常调用 :param response: :param exception: :param spider: :return: None,继续交给后续中间件处理异常;含 Response 或 Item 的可迭代对象(iterable),交给调度器或pipeline ''' return None def process_start_requests(self,start_requests, spider): ''' 爬虫启动时调用 :param start_requests: :param spider: :return: 包含 Request 对象的可迭代对象 ''' return start_requests 内置爬虫中间件: 'scrapy.contrib.spidermiddleware.httperror.HttpErrorMiddleware': 50, 'scrapy.contrib.spidermiddleware.offsite.OffsiteMiddleware': 500, 'scrapy.contrib.spidermiddleware.referer.RefererMiddleware': 700, 'scrapy.contrib.spidermiddleware.urllength.UrlLengthMiddleware': 800, 'scrapy.contrib.spidermiddleware.depth.DepthMiddleware': 900, """ # from scrapy.contrib.spidermiddleware.referer import RefererMiddleware # Enable or disable spider middlewares # See http://scrapy.readthedocs.org/en/latest/topics/spider-middleware.html SPIDER_MIDDLEWARES = { # 'step8_king.middlewares.SpiderMiddleware': 543, } """ 22. 下载中间件 class DownMiddleware1(object): def process_request(self, request, spider): ''' 请求需要被下载时,经过所有下载器中间件的process_request调用 :param request: :param spider: :return: None,继续后续中间件去下载; Response对象,停止process_request的执行,开始执行process_response Request对象,停止中间件的执行,将Request重新调度器 raise IgnoreRequest异常,停止process_request的执行,开始执行process_exception ''' pass def process_response(self, request, response, spider): ''' spider处理完成,返回时调用 :param response: :param result: :param spider: :return: Response 对象:转交给其他中间件process_response Request 对象:停止中间件,request会被重新调度下载 raise IgnoreRequest 异常:调用Request.errback ''' print('response1') return response def process_exception(self, request, exception, spider): ''' 当下载处理器(download handler)或 process_request() (下载中间件)抛出异常 :param response: :param exception: :param spider: :return: None:继续交给后续中间件处理异常; Response对象:停止后续process_exception方法 Request对象:停止中间件,request将会被重新调用下载 ''' return None 默认下载中间件 { 'scrapy.contrib.downloadermiddleware.robotstxt.RobotsTxtMiddleware': 100, 'scrapy.contrib.downloadermiddleware.httpauth.HttpAuthMiddleware': 300, 'scrapy.contrib.downloadermiddleware.downloadtimeout.DownloadTimeoutMiddleware': 350, 'scrapy.contrib.downloadermiddleware.useragent.UserAgentMiddleware': 400, 'scrapy.contrib.downloadermiddleware.retry.RetryMiddleware': 500, 'scrapy.contrib.downloadermiddleware.defaultheaders.DefaultHeadersMiddleware': 550, 'scrapy.contrib.downloadermiddleware.redirect.MetaRefreshMiddleware': 580, 'scrapy.contrib.downloadermiddleware.httpcompression.HttpCompressionMiddleware': 590, 'scrapy.contrib.downloadermiddleware.redirect.RedirectMiddleware': 600, 'scrapy.contrib.downloadermiddleware.cookies.CookiesMiddleware': 700, 'scrapy.contrib.downloadermiddleware.httpproxy.HttpProxyMiddleware': 750, 'scrapy.contrib.downloadermiddleware.chunked.ChunkedTransferMiddleware': 830, 'scrapy.contrib.downloadermiddleware.stats.DownloaderStats': 850, 'scrapy.contrib.downloadermiddleware.httpcache.HttpCacheMiddleware': 900, } """ # from scrapy.contrib.downloadermiddleware.httpauth import HttpAuthMiddleware # Enable or disable downloader middlewares # See http://scrapy.readthedocs.org/en/latest/topics/downloader-middleware.html # DOWNLOADER_MIDDLEWARES = { # 'step8_king.middlewares.DownMiddleware1': 100, # 'step8_king.middlewares.DownMiddleware2': 500, # } settings
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