使用scrapy框架爬虫实战

前言

Scrapy是一个爬虫框架，首先先进行安装scrapy，进入cmd，pip install scrapy。

创建爬虫项目

在cmd中输入scrapy startproject +项目名，进行创建一个爬虫项目

按照提示进入myzhifang文件夹，创建爬虫名称
cd myzhifang
scrapy genspider zhifang zhifang.com

这样就创建好了爬虫名

框架简单介绍

scrapy.cfg ：项目的配置文件
spiders文件夹：存储爬虫文件
zhifang.py：爬虫文件
items.py：项目的目标文件，如名字，价格等
pipelines.py：存储爬虫数据的文件
settings.py：项目设置文件

目标网站的分析

想爬取前10页的标题，价格，位置，图片url，以及整个详情的url
第1页网址：https://m.zhifang.com/project/03ah100000000000000.html
第2页：https://m.zhifang.com/project/03ah100000000000000_2.html
第5页：https://m.zhifang.com/project/03ah100000000000000_5.html
说明就是.html前面的数字在变化

上图找到标题，价格，位置，图片url，以及整个详情的url的位置，爬虫的时候可以使用css和xpath，与requests爬取语法基本相似。

改框架

settings.py

# Scrapy settings for myzhifang 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
import random

BOT_NAME = 'myzhifang'

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

# Crawl responsibly by identifying yourself (and your website) on the user-agent
# USER_AGENT = 'myzhifang (+http://www.yourdomain.com)'

# Obey robots.txt rules
#关闭机器协议
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
DOWNLOAD_DELAY = random.randint(3, 8)  # 请求间的延迟设置随机3-10秒
# 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:
#设置请求头
DEFAULT_REQUEST_HEADERS = {
    'Accept': 'text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8',
    'Accept-Language': 'en',
    'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/79.0.3945.130 Safari/537.36'
}

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

# Enable or disable downloader middlewares
# See https://docs.scrapy.org/en/latest/topics/downloader-middleware.html
# DOWNLOADER_MIDDLEWARES = {
#    'myzhifang.middlewares.MyzhifangDownloaderMiddleware': 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
#配制管道，用于下载数据
ITEM_PIPELINES = {
    'myzhifang.pipelines.MyzhifangPipeline': 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'

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 MyzhifangItem(scrapy.Item):
    # define the fields for your item here like:
    # name = scrapy.Field()
    title = scrapy.Field()
    price = scrapy.Field()
    address = scrapy.Field()
    pic_url = scrapy.Field()
    k_url = scrapy.Field()
    pass

pipelines.py

# useful for handling different item types with a single interface
from itemadapter import ItemAdapter
import csv

class MyzhifangPipeline:
    def __init__(self):
        #打开文件，写入类型，newline=''，消除空行
        self.file = open('zhifang_hefei.csv','w',encoding='utf-8',newline='')
        #切记，标题名要和item中的名字对应，不然会报错
        self.columns = ['title', 'price','address','pic_url','k_url']
        self.write = csv.DictWriter(self.file, fieldnames=self.columns)
        #写入首行
        self.write.writeheader()
    def process_item(self, item, spider):
        self.write.writerow(dict(item))
        return item
    def close(self,spider):
        self.file.close()

zhifang.py（爬虫文件）

import scrapy
from myzhifang.items import MyzhifangItem

class ZhifangSpider(scrapy.Spider):
    name = 'zhifang'
    allowed_domains = ['m.zhifang.com']
    start_urls = ['https://m.zhifang.com/project/03sd100000000000000_1.html']
    url = 'https://m.zhifang.com/project/03sd100000000000000_%d.html'
    page = 1

    def parse(self, response):
        item = MyzhifangItem()
        lists = response.xpath('//article[@class="article-wrap"]')
        for lis in lists:
            # 楼盘名称
            item['title'] = lis.xpath('./a/h2/text()').get()
            # 单价
            item['price'] = lis.xpath('./a/div[@class="content"]/p[@class="price"]/strong/text()').get()
            # 位置
            item['address'] = lis.xpath('./a/div[@class="content"]/p[@class="area"]/text()').get()
            # 图片url
            item['pic_url'] = 'http:' + lis.xpath('./a/div[@class="content"]/img/@src').get()
            # 详情url
            item['k_url'] = 'https://m.zhifang.com/' + lis.xpath('./a/@href').get()
            # print(k_url)
            yield item
        #爬取前十页的数据
        if self.page < 11:
            self.page += 1
            new_url = format(self.url % self.page)
            yield scrapy.Request(url=new_url, callback=self.parse)

爬取前十页的内容

运行爬虫文件

在终端输入：scrapy crawl zhifang，zhifang是你创建的爬虫名字

程序运行中

运行结束，出现一个zhifang_hefei.csv

至此，程序运行结束。