摘要：
Scrapy爬行器框架比网页爬行请求库具有更高的性能。刮痧的官方定义：刮痧是一种用于抓取网站和提取结构化数据的应用程序框架，可用于各种有用的应用程序，如数据挖掘、信息处理或历史归档。编写蜘蛛代码。写下小花。电子版的py文件：ScrapyDemoxiaohuarxiaohuarspiders。
学习爬虫有一段时间了，今天使用Scrapy框架将校花网的图片爬取到本地。Scrapy爬虫框架相对于使用requests库进行网页的爬取，拥有更高的性能。
Scrapy官方定义：Scrapy是用于抓取网站并提取结构化数据的应用程序框架，可用于广泛的有用应用程序，如数据挖掘，信息处理或历史存档。
建立Scrapy爬虫工程
在安装好Scrapy框架后，直接使用命令行进行项目的创建：
E:ScrapyDemo>scrapy startproject xiaohuar New Scrapy project 'xiaohuar', using template directory 'c:\users\lei\appdata\local\programs\python\python35\lib \site-packages\scrapy\templates\project', created in: E:ScrapyDemoxiaohuar You can start your first spider with: cd xiaohuar scrapy genspider example example.com
创建一个Scrapy爬虫
创建工程的时候，会自动创建一个与工程同名的目录，进入到目录中执行如下命令：
E:ScrapyDemoxiaohuar>scrapy genspider -t basic xiaohua xiaohuar.com Created spider 'xiaohua' using template 'basic' in module: xiaohuar.spiders.xiaohua
命令中"xiaohua"是生成Spider中*.py文件的文件名，"xiaohuar.com"是将要爬取网站的URL，可以在程序中更改。
编写Spider代码
编写E:ScrapyDemoxiaohuarxiaohuarspiders中的xiaohua.py文件。主要是配置URL和对请求到的页面的解析方式。
# -*- coding: utf-8 -*- import scrapy from scrapy.http import Request import re class XiaohuaSpider(scrapy.Spider): name = 'xiaohua' allowed_domains = ['xiaohuar.com'] start_urls = [] for i in range(43): url = "http://www.xiaohuar.com/list-1-%s.html" %i start_urls.append(url) def parse(self, response): if "www.xiaohuar.com/list-1" in response.url: # 下载的html源代码 html = response.text # 网页中图片存储地址：src="http://t.zoukankan.com/d/file/20160126/905e563421921adf9b6fb4408ec4e72f.jpg" # 通过正则匹配到所有的图片 # 获取的是图片的相对路径的列表 img_urls = re.findall(r'/d/file/d+/w+.jpg',html) # 使用循环对图片页进行请求 for img_url in img_urls: # 将图片的URL补全 if "http://" not in img_url: img_url = "http://www.xiaohuar.com%s" %img_url # 回调，返回response yield Request(img_url) else: # 下载图片 url = response.url # 保存的图片文件名 title = re.findall(r'w*.jpg',url)[0] # 保存图片 with open('E:\xiaohua_img\%s' % title, 'wb') as f: f.write(response.body)
这里使用正则表达式对图片的地址进行匹配，其他网页也都大同小异，需要根据具体的网页源代码进行分析。
运行爬虫
E:ScrapyDemoxiaohuar>scrapy crawl xiaohua 2017-10-22 22:30:11 [scrapy.utils.log] INFO: Scrapy 1.4.0 started (bot: xiaohuar) 2017-10-22 22:30:11 [scrapy.utils.log] INFO: Overridden settings: {'BOT_NAME': 'xiaohuar', 'SPIDER_MODULES': ['xiaohuar. spiders'], 'ROBOTSTXT_OBEY': True, 'NEWSPIDER_MODULE': 'xiaohuar.spiders'} 2017-10-22 22:30:11 [scrapy.middleware] INFO: Enabled extensions: ['scrapy.extensions.telnet.TelnetConsole', 'scrapy.extensions.corestats.CoreStats', 'scrapy.extensions.logstats.LogStats'] 2017-10-22 22:30:12 [scrapy.middleware] INFO: Enabled downloader middlewares: ['scrapy.downloadermiddlewares.robotstxt.RobotsTxtMiddleware', 'scrapy.downloadermiddlewares.httpauth.HttpAuthMiddleware', 'scrapy.downloadermiddlewares.downloadtimeout.DownloadTimeoutMiddleware', 'scrapy.downloadermiddlewares.defaultheaders.DefaultHeadersMiddleware', 'scrapy.downloadermiddlewares.useragent.UserAgentMiddleware', 'scrapy.downloadermiddlewares.retry.RetryMiddleware', 'scrapy.downloadermiddlewares.redirect.MetaRefreshMiddleware', 'scrapy.downloadermiddlewares.httpcompression.HttpCompressionMiddleware', 'scrapy.downloadermiddlewares.redirect.RedirectMiddleware', 'scrapy.downloadermiddlewares.cookies.CookiesMiddleware', 'scrapy.downloadermiddlewares.httpproxy.HttpProxyMiddleware', 'scrapy.downloadermiddlewares.stats.DownloaderStats'] 2017-10-22 22:30:12 [scrapy.middleware] INFO: Enabled spider middlewares: ['scrapy.spidermiddlewares.httperror.HttpErrorMiddleware', 'scrapy.spidermiddlewares.offsite.OffsiteMiddleware', 'scrapy.spidermiddlewares.referer.RefererMiddleware', 'scrapy.spidermiddlewares.urllength.UrlLengthMiddleware', 'scrapy.spidermiddlewares.depth.DepthMiddleware'] 2017-10-22 22:30:12 [scrapy.middleware] INFO: Enabled item pipelines: [] 2017-10-22 22:30:12 [scrapy.core.engine] INFO: Spider opened 2017-10-22 22:30:12 [scrapy.extensions.logstats] INFO: Crawled 0 pages (at 0 pages/min), scraped 0 items (at 0 items/min ) 2017-10-22 22:30:12 [scrapy.extensions.telnet] DEBUG: Telnet console listening on 127.0.0.1:6023 2017-10-22 22:30:12 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://www.xiaohuar.com/robots.txt> (referer: None) 2017-10-22 22:30:13 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://www.xiaohuar.com/list-1-0.html> (referer: None ) 2017-10-22 22:30:13 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://www.xiaohuar.com/d/file/20170721/cb96f1b106b3d b4a6bfcf3d2e880dea0.jpg> (referer: http://www.xiaohuar.com/list-1-0.html) 2017-10-22 22:30:13 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://www.xiaohuar.com/d/file/20170824/dcc166b0eba6a 37e05424cfc29023121.jpg> (referer: http://www.xiaohuar.com/list-1-0.html) 2017-10-22 22:30:13 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://www.xiaohuar.com/d/file/20170916/7f78145b1ca16 2eb814fbc03ad24fbc1.jpg> (referer: http://www.xiaohuar.com/list-1-0.html) 2017-10-22 22:30:13 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://www.xiaohuar.com/d/file/20170919/2f728d0f110a2 1fea95ce13e0b010d06.jpg> (referer: http://www.xiaohuar.com/list-1-0.html) 2017-10-22 22:30:13 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://www.xiaohuar.com/d/file/20170819/9c3dfeef7e08c c0303ce233e4ddafa7f.jpg> (referer: http://www.xiaohuar.com/list-1-0.html) 2017-10-22 22:30:14 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://www.xiaohuar.com/d/file/20170917/715515e7fe1f1 cb9fd388bbbb00467c2.jpg> (referer: http://www.xiaohuar.com/list-1-0.html) 2017-10-22 22:30:14 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://www.xiaohuar.com/d/file/20170628/f3d06ef49965a edbe18286a2f221fd9f.jpg> (referer: http://www.xiaohuar.com/list-1-0.html) 2017-10-22 22:30:14 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://www.xiaohuar.com/d/file/20170513/6121e3e90ff3b a4c9398121bda1dd582.jpg> (referer: http://www.xiaohuar.com/list-1-0.html) 2017-10-22 22:30:14 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://www.xiaohuar.com/d/file/20170516/6e295fe48c332 45be858c40d37fb5ee6.jpg> (referer: http://www.xiaohuar.com/list-1-0.html) 2017-10-22 22:30:14 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://www.xiaohuar.com/d/file/20170707/f7ca636f73937 e33836e765b7261f036.jpg> (referer: http://www.xiaohuar.com/list-1-0.html) 2017-10-22 22:30:14 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://www.xiaohuar.com/d/file/20170528/b352258c83776 b9a2462277dec375d0c.jpg> (referer: http://www.xiaohuar.com/list-1-0.html) 2017-10-22 22:30:14 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://www.xiaohuar.com/d/file/20170527/4a7a7f1e6b69f 126292b981c90110d0a.jpg> (referer: http://www.xiaohuar.com/list-1-0.html) 2017-10-22 22:30:14 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://www.xiaohuar.com/d/file/20170715/61110ba027f00 4fb503ff09cdee44d0c.jpg> (referer: http://www.xiaohuar.com/list-1-0.html) 2017-10-22 22:30:14 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://www.xiaohuar.com/d/file/20170520/dd21a21751e24 a8f161792b66011688c.jpg> (referer: http://www.xiaohuar.com/list-1-0.html) 2017-10-22 22:30:15 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://www.xiaohuar.com/d/file/20170529/8140c4ad797ca 01f5e99d09c82dd8a42.jpg> (referer: http://www.xiaohuar.com/list-1-0.html) 2017-10-22 22:30:15 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://www.xiaohuar.com/d/file/20170603/e55f77fb3aa3c 7f118a46eeef5c0fbbf.jpg> (referer: http://www.xiaohuar.com/list-1-0.html) 2017-10-22 22:30:15 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://www.xiaohuar.com/d/file/20170529/e5902d4d3e408 29f9a0d30f7488eab84.jpg> (referer: http://www.xiaohuar.com/list-1-0.html) 2017-10-22 22:30:15 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://www.xiaohuar.com/d/file/20170604/ec3794d0d42b5 38bf4461a84dac32509.jpg> (referer: http://www.xiaohuar.com/list-1-0.html) 2017-10-22 22:30:15 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://www.xiaohuar.com/d/file/20170603/c34b29f68e8f9 6d44c63fe29bf4a66b8.jpg> (referer: http://www.xiaohuar.com/list-1-0.html) 2017-10-22 22:30:15 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://www.xiaohuar.com/d/file/20170701/fb18711a6af87 f30942d6a19f6da6b3e.jpg> (referer: http://www.xiaohuar.com/list-1-0.html) 2017-10-22 22:30:15 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://www.xiaohuar.com/d/file/20170619/e0456729d4dcb ea569a1acbc6a47ab69.jpg> (referer: http://www.xiaohuar.com/list-1-0.html) 2017-10-22 22:30:15 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://www.xiaohuar.com/d/file/20170626/0ab1d89f54c90 df477a90aa533ceea36.jpg> (referer: http://www.xiaohuar.com/list-1-0.html) 2017-10-22 22:30:15 [scrapy.core.engine] INFO: Closing spider (finished) 2017-10-22 22:30:15 [scrapy.statscollectors] INFO: Dumping Scrapy stats: {'downloader/request_bytes': 8785, 'downloader/request_count': 24, 'downloader/request_method_count/GET': 24, 'downloader/response_bytes': 2278896, 'downloader/response_count': 24, 'downloader/response_status_count/200': 24, 'finish_reason': 'finished', 'finish_time': datetime.datetime(2017, 10, 22, 14, 30, 15, 892287), 'log_count/DEBUG': 25, 'log_count/INFO': 7, 'request_depth_max': 1, 'response_received_count': 24, 'scheduler/dequeued': 23, 'scheduler/dequeued/memory': 23, 'scheduler/enqueued': 23, 'scheduler/enqueued/memory': 23, 'start_time': datetime.datetime(2017, 10, 22, 14, 30, 12, 698874)} 2017-10-22 22:30:15 [scrapy.core.engine] INFO: Spider closed (finished)
图片保存
在图片保存过程中""需要进行转义。
>>> import requests
>>> r = requests.get("https://timgsa.baidu.com/timg?image&quality=80&size=b9999_10000&sec=1508693697147&di=23eb655d8e450f84cf39453bc1029bc0&imgtype=0&src=http%3A%2F%2Fb.hiphotos.baidu.com%2Fimage%2Fpic%2Fitem%2Fc9fcc3cec3fdfc038b027f7bde3f8794a5c226fe.jpg") >>> open("E:xiaohua_img