标签:item url self 链家 爬取 二手房 scrapy html https
1、首先感谢肖祥博主的案例:https://www.cnblogs.com/xiao987334176/p/13739249.html
2、环境安装
(1)安装Anaconda:
下载地址:https://www.anaconda.com/products/individual
(2)安装:scrapy
(3)安装:Pycharm
(4)安装:Xpath helper
教程参考:
获取插件:https://blog.csdn.net/weixin_41010318/article/details/86472643
配置过程:https://www.cnblogs.com/pfeiliu/p/13483562.html
3、爬取过程
(1)网页分析:
网址:
第一页:https://bj.lianjia.com/ershoufang/
第二页:https://bj.lianjia.com/ershoufang/pg1/
末尾页:https://bj.lianjia.com/ershoufang/pg100/
利用xpath helper 分析出房源的链家编号:
(2)详细代码:
目录:
创建项目:
# 打开Pycharm,并打开Terminal,执行以下命令
scrapy startproject fang
cd fang
scrapy genspider lianjia bj.lianjia.com/ershoufang
在scrapy.cfg同级目录,创建bi.py,用于启动Scrapy项目,内容如下:
# !/usr/bin/python3 # -*- coding: utf-8 -*- # 在项目根目录下新建:bi.py from scrapy.cmdline import execute # 第三个参数是:爬虫程序名 # --nolog什么意思? execute(['scrapy', 'crawl', 'lianjia', '--nolog'])View Code
lianjia.py
# -*- coding: utf-8 -*- import scrapy from scrapy import Request # 导入模块 import math import re from fang.items import FangItem from selenium.webdriver import ChromeOptions from selenium.webdriver import Chrome class LianjiaSpider(scrapy.Spider): name = 'lianjia' allowed_domains = ['bj.lianjia.com'] # start_urls = ['http://bj.lianjia.com/ershoufang/'] base_url = "https://bj.lianjia.com/ershoufang/pg" # 实例化一个浏览器对象 def __init__(self): # 防止网站识别Selenium代码 # selenium启动配置参数接收是ChromeOptions类,创建方式如下: options = ChromeOptions() # 添加启动参数 # 浏览器不提供可视化页面. linux下如果系统不支持可视化不加这条会启动失败 options.add_argument("--headless") # => 为Chrome配置无头模式 # 添加实验性质的设置参数 # 设置开发者模式启动,该模式下webdriver属性为正常值 options.add_experimental_option('excludeSwitches', ['enable-automation']) options.add_experimental_option('useAutomationExtension', False) # 禁用浏览器弹窗 self.browser = Chrome(options=options) # 最新解决navigator.webdriver=true的方法 self.browser.execute_cdp_cmd("Page.addScriptToEvaluateOnNewDocument", { "source": """ Object.defineProperty(navigator, 'webdriver', { get: () => undefined }) """ }) super().__init__() def start_requests(self): print("开始爬虫") self.base_url = "https://bj.lianjia.com/ershoufang/pg" url = self.base_url + str(2) print("url", url) # url = "https://news.163.com/" # 一个Request对象表示一个HTTP请求,它通常是在爬虫生成,并由下载执行,从而生成Response # url(string) - 此请求的网址 # callback(callable) - 将使用此请求的响应(一旦下载)作为其第一个参数调用的函数。 # 如果请求没有指定回调,parse()将使用spider的 方法。请注意,如果在处理期间引发异常,则会调用errback。 # 仍有许多参数:method='GET', headers, body, cookies, meta, encoding='utf-8', priority=0, dont_filter=False, errback response = scrapy.Request(url, callback=self.parse_index) yield response # 整个爬虫结束后关闭浏览器 def close(self, spider): print("关闭爬虫") self.browser.quit() # 访问主页的url, 拿到对应板块的response def parse_index(self, response): print("访问主页") # 获取分页 # 查询条数 ret_num = 3000 # print("ret_num", ret_num, type(ret_num)) # 计算分页,每一页30条 jsfy = int(ret_num) / 30 # 向上取整 page_num = math.ceil(jsfy) # print("page_num",page_num) for n in range(2, page_num + 1): n += 1 # 下一页url url = self.base_url + str(n) print("url", url) # 访问下一页,有返回时,调用self.parse_details方法 yield scrapy.Request(url=url, callback=self.parse_details) def parse_details(self, response): # 获取页面中要抓取的信息在网页中位置节点 node_list = response.xpath('//ul[@class="sellListContent"]/li/div[1]') count = 0 # 遍历节点,进入详情页,获取其他信息 for node in node_list: count += 1 try: # # 名称 BeiJingFangYuan_Id = node.xpath('./div[@class="title"]/a/@href').extract() if BeiJingFangYuan_Id: BeiJingFangYuan_Id = BeiJingFangYuan_Id[0].strip() print("BeiJingFangYuan_Id", BeiJingFangYuan_Id) # item item = FangItem() item['BeiJingFangYuan_Id'] = BeiJingFangYuan_Id yield item except Exception as e: print(e) print("本次爬取数据: %s条" % count) '''def parse(self, response): pass '''View Code
items.py
# Define here the models for your scraped items # # See documentation in: # https://docs.scrapy.org/en/latest/topics/items.html import scrapy class FangItem(scrapy.Item): # define the fields for your item here like: # name = scrapy.Field() BeiJingFangYuan_Id = scrapy.Field() passView Code
pipelines.py
# Define your item pipelines here # # Don't forget to add your pipeline to the ITEM_PIPELINES setting # See: https://docs.scrapy.org/en/latest/topics/item-pipeline.html # useful for handling different item types with a single interface from itemadapter import ItemAdapter import json class FangPipeline(object): def __init__(self): # python3保存文件 必须需要'wb' 保存为json格式 # 为了方便,保存在一个json文件中。当然,也可以设置保存到数据库中。 self.f = open("fang_pipline.json", 'wb') # 在pipeline中写json文件 def process_item(self, item, spider): # 读取item中的数据 并换行处理 # json.dumps 序列化时对中文默认使用的ascii编码.想输出真正的中文需要指定ensure_ascii=False content = json.dumps(dict(item), ensure_ascii=False) + ',\n' # f.write写入中文出错解决方法 self.f.write(content.encode('utf=8')) return item def close_spider(self, spider): # 关闭文件 self.f.close()View Code
修改settings.py,应用pipelines
# Scrapy settings for fang project # # For simplicity, this file contains only settings considered important or # commonly used. You can find more settings consulting the documentation: # # https://docs.scrapy.org/en/latest/topics/settings.html # https://docs.scrapy.org/en/latest/topics/downloader-middleware.html # https://docs.scrapy.org/en/latest/topics/spider-middleware.html BOT_NAME = 'fang' SPIDER_MODULES = ['fang.spiders'] NEWSPIDER_MODULE = 'fang.spiders' # Crawl responsibly by identifying yourself (and your website) on the user-agent #USER_AGENT = 'fang (+http://www.yourdomain.com)' # 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://docs.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://docs.scrapy.org/en/latest/topics/spider-middleware.html #SPIDER_MIDDLEWARES = { # 'fang.middlewares.FangSpiderMiddleware': 543, #} # Enable or disable downloader middlewares # See https://docs.scrapy.org/en/latest/topics/downloader-middleware.html #DOWNLOADER_MIDDLEWARES = { # 'fang.middlewares.FangDownloaderMiddleware': 543, #} # Enable or disable extensions # See https://docs.scrapy.org/en/latest/topics/extensions.html #EXTENSIONS = { # 'scrapy.extensions.telnet.TelnetConsole': None, #} # Configure item pipelines # See https://docs.scrapy.org/en/latest/topics/item-pipeline.html ITEM_PIPELINES = { 'fang.pipelines.FangPipeline': 300, } # Enable and configure the AutoThrottle extension (disabled by default) # See https://docs.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://docs.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'View Code
执行bi.py,启动爬虫项目,效果如下:
标签:item,url,self,链家,爬取,二手房,scrapy,html,https 来源: https://www.cnblogs.com/mrfanqie/p/lianjiaproject_01.html
本站声明: 1. iCode9 技术分享网(下文简称本站)提供的所有内容,仅供技术学习、探讨和分享; 2. 关于本站的所有留言、评论、转载及引用,纯属内容发起人的个人观点,与本站观点和立场无关; 3. 关于本站的所有言论和文字,纯属内容发起人的个人观点,与本站观点和立场无关; 4. 本站文章均是网友提供,不完全保证技术分享内容的完整性、准确性、时效性、风险性和版权归属;如您发现该文章侵犯了您的权益,可联系我们第一时间进行删除; 5. 本站为非盈利性的个人网站,所有内容不会用来进行牟利,也不会利用任何形式的广告来间接获益,纯粹是为了广大技术爱好者提供技术内容和技术思想的分享性交流网站。