1.下载方式

widows ，打开一个cmd，输入pip install scrapy（必须安装python环境）

2. 新建一个项目

scrapy startproject 项目名 

3.自动生成一个爬取百度的py文件 

scrapy genspider baidu www.baidu.com

spiders下的baidu.py是scrapy自动为我们生成的

4. 项目的配置文件settings.py  

# Scrapy settings for myfirstPj 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 = 'myfirstPj'

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


# Crawl responsibly by identifying yourself (and your website) on the user-agent
# USER_AGENT：默认是注释的，这个东西非常重要，如果不写很容易被判断为电脑，简单点洗一个Mozilla/5.0即可
#USER_AGENT = 'myfirstPj (+http://www.yourdomain.com)'

# Obey robots.txt rules
# ROBOTSTXT_OBEY：是否遵循机器人协议，默认是true，需要改为false，否则很多东西爬不了
ROBOTSTXT_OBEY = False

# Configure maximum concurrent requests performed by Scrapy (default: 16)
#  CONCURRENT_REQUESTS：最大并发数，很好理解，就是同时允许开启多少个爬虫线程
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：下载延迟时间，单位是秒，控制爬虫爬取的频率，根据你的项目调整，不要太快也不要太慢，默认是3秒，即爬一个停3秒，设置为1秒性价比较高，如果要爬取的文件较多，写零点几秒也行
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)
# COOKIES_ENABLED：是否保存COOKIES，默认关闭，开机可以记录爬取过程中的COKIE，非常好用的一个参数
#TELNETCONSOLE_ENABLED = False

# Override the default request headers:
# DEFAULT_REQUEST_HEADERS：默认请求头，上面写了一个USER_AGENT，其实这个东西就是放在请求头里面的，这个东西可以根据你爬取的内容做相应设置。
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 6.2; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/27.0.1453.94 Safari/537.36'
}


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

# Enable or disable downloader middlewares
# See https://docs.scrapy.org/en/latest/topics/downloader-middleware.html
#DOWNLOADER_MIDDLEWARES = {
#    'myfirstPj.middlewares.MyfirstpjDownloaderMiddleware': 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：项目管道，300为优先级，越低越爬取的优先度越高
ITEM_PIPELINES = {
   'myfirstPj.pipelines.MyfirstpjPipeline': 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'

# 日志等级与日志保存
# 1.DEBUG 调试信息
# 2.INFO 一般信息
# 3.WARNING 警告
# 4.ERROR 普通错误
# 5.CRITICAL 严重错误
LOG_LEVEL = "WARNING"
LOG_FILE = "logs/test.log"

5. 修改定义的数据结构item

# Define here the models for your scraped items
#
# See documentation in:
# https://docs.scrapy.org/en/latest/topics/items.html

import scrapy


class MyfirstpjItem(scrapy.Item):
    # define the fields for your item here like:
    # name = scrapy.Field()
    name = scrapy.Field()
    description = scrapy.Field()

6.编写爬虫程序，在spiders下的爬虫文件

import scrapy
from ..items import MyfirstpjItem


class BaiduSpider(scrapy.Spider):
    name = 'baidu'
    allowed_domains = ['v.qq.com']
    start_urls = ['https://v.qq.com/x/bu/pagesheet/list?append=1&channel=cartoon&iarea=1&listpage=2&offset=0&pagesize=30']
    offset = 0

    def parse(self, response):
        items = MyfirstpjItem()
        lists = response.xpath('//div[@class="list_item"]')
        for i in lists:
            items['name'] = i.xpath('./a/@title').get()
            items['description'] = i.xpath('./div/div/@title').get()

            yield items

        if self.offset < 120:
            self.offset += 30
            url = 'https://v.qq.com/x/bu/pagesheet/list?append=1&channel=cartoon&iarea=1&listpage=2&offset={}&pagesize=30'.format(
                str(self.offset))

            yield scrapy.Request(url=url, callback=self.parse)

7.交给管道输出

# 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


class MyfirstpjPipeline:
    def process_item(self, item, spider):
        print(item)
        return item

9.新建日志文件夹

10. 运行文件

#!/usr/bin/env python  
# -*- coding:utf-8 _*-  
""" 
@author:拾壹
@Time: 2021/8/30 16:35
"""
from scrapy import cmdline

# cmdline.execute('scrapy crawl baidu'.split())
cmdline.execute('scrapy crawl baidu -o baidu.csv'.split())
# cmdline.execute('scrapy crawl baidu -o baidu.json'.split())

11. 运行结果