@Author:BY Runsen
前言
在前幾天,接到一個大學生的作業的爬蟲單子,要求採用scrapy爬取鏈家官方網站新房的數據(3-5頁即可,太多可能被封禁ip),網址:https://bj.fang.lianjia.com/loupan/,將樓盤名稱、價格、平米數等(可以拓展)數據保存到一個json文件中。
為了50塊錢,廢話不說就是開幹。雖說我不是計算機的,還是一個屌絲大三化工學生。
分析網頁
那麼今天教大家用Scarpy爬取鏈家網,爬取網頁如下:http://bj.fang.lianjia.com/loupan/。
點擊其中的一個來看看,https://bj.fang.lianjia.com/loupan/p_zjtfbkrhf/?fb_expo_id=303816048586158080
新建項目
新建項目和爬蟲文件這些太簡單,都是老套路, pass了。新建的項目如下。
加請求頭
第一步,傻逼都知道加請求頭。
在setting.py加MY_USER_AGENT
<code>MY_USER_AGENT = [ "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1; AcooBrowser; .NET CLR 1.1.4322; .NET CLR 2.0.50727)", "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0; Acoo Browser; SLCC1; .NET CLR 2.0.50727; Media Center PC 5.0; .NET CLR 3.0.04506)", "Mozilla/4.0 (compatible; MSIE 7.0; AOL 9.5; AOLBuild 4337.35; Windows NT 5.1; .NET CLR 1.1.4322; .NET CLR 2.0.50727)", "Mozilla/5.0 (Windows; U; MSIE 9.0; Windows NT 9.0; en-US)", "Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; Win64; x64; Trident/5.0; .NET CLR 3.5.30729; .NET CLR 3.0.30729; .NET CLR 2.0.50727; Media Center PC 6.0)", "Mozilla/5.0 (compatible; MSIE 8.0; Windows NT 6.0; Trident/4.0; WOW64; Trident/4.0; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; .NET CLR 1.0.3705; .NET CLR 1.1.4322)", "Mozilla/4.0 (compatible; MSIE 7.0b; Windows NT 5.2; .NET CLR 1.1.4322; .NET CLR 2.0.50727; InfoPath.2; .NET CLR 3.0.04506.30)", "Mozilla/5.0 (Windows; U; Windows NT 5.1; zh-CN) AppleWebKit/523.15 (KHTML, like Gecko, Safari/419.3) Arora/0.3 (Change: 287 c9dfb30)", "Mozilla/5.0 (X11; U; Linux; en-US) AppleWebKit/527+ (KHTML, like Gecko, Safari/419.3) Arora/0.6", "Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.1.2pre) Gecko/20070215 K-Ninja/2.1.1", "Mozilla/5.0 (Windows; U; Windows NT 5.1; zh-CN; rv:1.9) Gecko/20080705 Firefox/3.0 Kapiko/3.0", "Mozilla/5.0 (X11; Linux i686; U;) Gecko/20070322 Kazehakase/0.4.5", "Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.0.8) Gecko Fedora/1.9.0.8-1.fc10 Kazehakase/0.5.6", "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/535.11 (KHTML, like Gecko) Chrome/17.0.963.56 Safari/535.11", "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_7_3) AppleWebKit/535.20 (KHTML, like Gecko) Chrome/19.0.1036.7 Safari/535.20", "Opera/9.80 (Macintosh; Intel Mac OS X 10.6.8; U; fr) Presto/2.9.168 Version/11.52", "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/536.11 (KHTML, like Gecko) Chrome/20.0.1132.11 TaoBrowser/2.0 Safari/536.11", "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.1 (KHTML, like Gecko) Chrome/21.0.1180.71 Safari/537.1 LBBROWSER", "Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; WOW64; Trident/5.0; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; Media Center PC 6.0; .NET4.0C; .NET4.0E; LBBROWSER)", "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1; QQDownload 732; .NET4.0C; .NET4.0E; LBBROWSER)", "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/535.11 (KHTML, like Gecko) Chrome/17.0.963.84 Safari/535.11 LBBROWSER", "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.1; WOW64; Trident/5.0; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; Media Center PC 6.0; .NET4.0C; .NET4.0E)", "Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; WOW64; Trident/5.0; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; Media Center PC 6.0; .NET4.0C; .NET4.0E; QQBrowser/7.0.3698.400)", "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1; QQDownload 732; .NET4.0C; .NET4.0E)", "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; Trident/4.0; SV1; QQDownload 732; .NET4.0C; .NET4.0E; 360SE)", "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1; QQDownload 732; .NET4.0C; .NET4.0E)", "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.1; WOW64; Trident/5.0; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; Media Center PC 6.0; .NET4.0C; .NET4.0E)", "Mozilla/5.0 (Windows NT 5.1) AppleWebKit/537.1 (KHTML, like Gecko) Chrome/21.0.1180.89 Safari/537.1", "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.1 (KHTML, like Gecko) Chrome/21.0.1180.89 Safari/537.1", "Mozilla/5.0 (iPad; U; CPU OS 4_2_1 like Mac OS X; zh-cn) AppleWebKit/533.17.9 (KHTML, like Gecko) Version/5.0.2 Mobile/8C148 Safari/6533.18.5", "Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:2.0b13pre) Gecko/20110307 Firefox/4.0b13pre", "Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:16.0) Gecko/20100101 Firefox/16.0", "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.11 (KHTML, like Gecko) Chrome/23.0.1271.64 Safari/537.11", "Mozilla/5.0 (X11; U; Linux x86_64; zh-CN; rv:1.9.2.10) Gecko/20100922 Ubuntu/10.10 (maverick) Firefox/3.6.10", "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/58.0.3029.110 Safari/537.36", ] /<code>
然後去Middleware.py去搞一個RandomUserAgentMiddleware,這代碼找之前的scrapy爬蟲項目直接複製,簡單。
<code> import random class RandomUserAgentMiddleware(object): def __init__(self, user_agents): self.user_agents = user_agents @classmethod def from_crawler(cls, crawler): # 從settings.py中導入MY_USER_AGENT s = cls(user_agents=crawler.settings.get('MY_USER_AGENT')) return s def process_request(self, request, spider): agent = random.choice(self.user_agents) request.headers['User-Agent'] = agent return None /<code>
去setting.py開啟上它。900記得, 老套路。
<code>DOWNLOADER_MIDDLEWARES = { # 'lianjia.middlewares.LianjiaDownloaderMiddleware': 543, 'lianjia.middlewares.RandomUserAgentMiddleware': 900, } /<code>
OK,請求頭headers搞定,代碼都是複製的,3分鐘OK。
搞定item
item就是把爬取的信息儲存起來,爬取樓盤名稱、類型,位置,價格、平米數,代碼編寫需要兩分鐘。
<code>import scrapy ''' 目標:爬取鏈家官方網站新房的數據(3-5頁即可,太多可能被封禁ip) 網址:https://bj.fang.lianjia.com/loupan/ 要求:將樓盤名稱、價格、平米數等(可以拓展)數據保存到一個json文件中。 交付:整個project的壓縮包 ''' class LianjiaItem(scrapy.Item): # define the fields for your item here like: # name = scrapy.Field() """樓盤名稱、類型,位置,價格、平米數""" name = scrapy.Field() type = scrapy.Field() location = scrapy.Field() price = scrapy.Field() number = scrapy.Field() /<code>
首頁調試
我們需要把詳情頁的url和建面面積匹配出來,scrapy shell https://bj.fang.lianjia.com/loupan進入shell調試。
在url的a標籤發現了class = “resblock-name”的div,下面就是小兒科的東西。
沒有域名,直接follow快捷方式完事,可以自動拼接url。
建面面積一樣,輕鬆解決。
在span標籤發現了class = “resblock-area”的div,重複下面的操作。
詳情頁調試
下面就是詳情頁了,scrapy shell https://bj.fang.lianjia.com/loupan/p_zjtfbkrhf/?fb_expo_id=303816048586158080
下面把樓盤名稱搞出來,慢慢調試。
樓盤類型,位置,價格這些,我不一一找了。就是耐心的通過scrapy shell 調試。這裡花費了有半個小時。
最後,自己看代碼。
<code>import scrapy from ..items import LianjiaItem class SpiderSpider(scrapy.Spider): name = 'spider' allowed_domains = ['bj.fang.lianjia.com'] start_urls = ['http://bj.fang.lianjia.com/loupan/'] def parse(self, response): for i in range(1,22): page_url = 'https://bj.fang.lianjia.com/loupan/pg{}'.format(i) yield response.follow(page_url,callback =self.parse_page) def parse_page(self,response): urls = response.xpath("//div[@class='resblock-name']/a/@href").extract() nums = response.xpath("//div[@class='resblock-area']/span/text()").extract() print(urls) print(nums) for num,url in zip(nums,urls): # 用的follow快捷方式,可以自動拼接url yield response.follow(url=url, meta={'num':num},callback=self.parse_detail) def parse_detail(self,response): item = LianjiaItem() item['name'] = response.xpath("//div[@class='title-wrap']//h2/text()").extract_first() self.logger.info('正在爬取{}……'.format(item['name'])) item['type'] = response.xpath("//div[@class='tags-wrap']/span[@class='tag-item house-type-tag']/text()").extract_first() item['location'] = response.xpath("//ul[@class='info-list']//span[@class='content']/text()").extract_first() item['price'] = response.xpath("//div[@class='price']/span[@class='price-number']/text()").extract_first() item['number'] = response.meta['num'] yield item /<code>
保存json
要求保存json,直接 -o 省事,連Pipeline都不用寫。
在setting中開啟Pipeline。
<code>ITEM_PIPELINES = { 'lianjia.pipelines.LianjiaPipeline': 300, } /<code>
運行,開一個main.py,scrapy crawl spider -o spider.json
<code>''' @Author: Runsen @微信公眾號: 潤森筆記 @博客: https://blog.csdn.net/weixin_44510615 @Date: 2020/4/13 ''' import sys import os from scrapy.cmdline import execute sys.path.append(os.path.dirname(os.path.abspath(__file__))) execute(['scrapy','crawl','spider','-o spider.json']) /<code>
運行時發現沒有中文,看了下我scrapy博客https://maoli.blog.csdn.net/article/details/89012106,加上setting配置FEED_EXPORT_ENCODING = 'utf-8'完成。
<code>FEED_EXPORT_ENCODING = 'utf-8' /<code>
運行,ok
一個小時多點,50塊到手。最後,我對不起顧客了,把代碼公開了,給老師發現那慘了。