导览

1. Scrapy install

2. Scrapy 项目创建

3. Scrapy 自定义爬虫类

4. Scrapy 处理逻辑

5. Scrapy 扩展

1. Scrapy install

准备知识

pip 包管理
Python 安装
Xpath
Css

Windows安装 Scrapy

$>- pip install scrapy

Linux安装 Scrapy

$>- apt-get install python-scrapy

2. Scrapy 项目创建

在开始爬取之前，必须创建一个新的Scrapy项目。进入自定义的项目目录中，运行下列命令：

$>- scrapy startproject mySpider

其中， mySpider 为项目名称，可以看到将会创建一个 mySpider 文件夹，使用命令查看目录结构

$>- tree mySpider

3. Scrapy 自定义爬虫类

通过Scrapy的Spider基础模版顺便建立一个基础的爬虫。（也可以不用Scrapy命令建立基础爬虫，）

$>- scrapy genspider gzrbSpider dayoo.com

scrapy genspider是一个命令，也是scrapy最常用的几个命令之一。至此，一个最基本的爬虫项目已经建立完毕了.

文件描述：

序列	文件名	描述
1	scrapy.cfg	是整个Scrapy项目的配置文件
2	settings.py	是上层目录中scrapy.cfg定义的设置文件(决定由谁去处理爬取的内容)
3	init.pyc	是__init__.py的字节码文件
4	init.py	作用就是将它的上级目录变成了一个模块，否则，文件夹没有__init__.py不能作为模块导入
5	items.py	是定义爬虫最终需要哪些项 (决定爬取哪些项目)
5	pipelines.py	Scrapy爬虫爬取了网页中的内容后，这些内容怎么处理就取决于pipelines.py如何设置 (决定爬取后的内容怎样处理)
6	gzrbSpider.py	自定义爬虫类（决定怎么爬）

命令描述：

序列	操作	描述
1	模拟爬广州日报网页	scrapy shell https://www.dayoo.com
2	模拟查看节点数据	response.xpath('.//div[@class="mt35"]//ul[@class="news-list"]').extract()
3	运行爬虫	scrapy crawl gzrbSpider

序列

操作

描述

模拟爬广州日报网页

scrapy shell https://www.dayoo.com

模拟查看节点数据

response.xpath('.//div[@class="mt35"]//ul[@class="news-list"]').extract()

运行爬虫

scrapy crawl gzrbSpider

4. Scrapy 处理逻辑

文件 \spiders\gzrbSpider.py

import scrapy
from mySpider.items import MySpiderItemclass gzrbSpider(scrapy.Spider):name = "gzrbSpider"allowed_domains = ["dayoo.com/"]start_urls = ('https://www.dayoo.com',)def parse(self, response):subSelector = response.xpath('.//div[@class="mt35"]//ul[@class="news-list"]')items = []for sub in subSelector:item = MySpiderItem()item['newName'] = sub.xpath('./li/a/text()').extract()items.append(item)return items

文件 Item.py

# Define here the models for your scraped items
#
# See documentation in:
# https://docs.scrapy.org/en/latest/topics/items.htmlimport scrapyclass MySpiderItem(scrapy.Item):# define the fields for your item here like:# name = scrapy.Field()newName = scrapy.Field()

文件 Setting.py

# Scrapy settings for mySpider 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.htmlBOT_NAME = 'mySpider'SPIDER_MODULES = ['mySpider.spiders']
NEWSPIDER_MODULE = 'mySpider.spiders'# Crawl responsibly by identifying yourself (and your website) on the user-agent
#USER_AGENT = 'mySpider(+http://www.yourdomain.com)'# Obey robots.txt rules
ROBOTSTXT_OBEY = True# 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 = {
#    'mySpider.middlewares.mySpiderSpiderMiddleware': 543,
#}# Enable or disable downloader middlewares
# See https://docs.scrapy.org/en/latest/topics/downloader-middleware.html
#DOWNLOADER_MIDDLEWARES = {
#    'mySpider.middlewares.mySpiderDownloaderMiddleware': 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 = {'mySpider.pipelines.mySpiderPipeline': 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'

文件 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 time# class mySpiderPipeline:
#     def process_item(self, item, spider):
#         return itemclass MySpiderPipeline(object):def process_item(self, item, spider):now = time.strftime('%Y-%m-%d', time.localtime())fileName = 'gzrb' + now + '.txt'for it in item['newName ']:with open(fileName,encoding='utf-8',mode = 'a') as fp:# fp.write(item['newName '][0].encode('utf8') + '\n\n')fp.write(it + '\n\n')return item

本文代码结果展示：

5. Scrapy 扩展

Xpath:

Css:

Python Scrapy 爬虫简单教程相关推荐

Python网络爬虫简单教程——第一部
Python网络爬虫简单教程--第一部感谢,如需转载请注明文章出处:https://blog.csdn.net/weixin_44609873/article/details/103384984 P ...
Python Scrapy爬虫框架实战应用
通过上一节<Python Scrapy爬虫框架详解>的学习,您已经对 Scrapy 框架有了一个初步的认识,比如它的组件构成,配置文件,以及工作流程.本节将通过一个的简单爬虫项目对 Scr ...
scrapy爬虫框架教程（二）-- 爬取豆瓣电影
前言经过上一篇教程我们已经大致了解了Scrapy的基本情况,并写了一个简单的小demo.这次我会以爬取豆瓣电影TOP250为例进一步为大家讲解一个完整爬虫的流程. 工具和环境语言:python 2 ...
Scrapy爬虫入门教程五 Selectors（选择器）
Scrapy爬虫入门教程一安装和基本使用 Scrapy爬虫入门教程二官方提供Demo Scrapy爬虫入门教程三命令行工具介绍和示例 Scrapy爬虫入门教程四 Spider(爬虫) Scrap ...
python商业爬虫教程_廖雪峰老师的Python商业爬虫课程 Python网络爬虫实战教程体会不一样的Python爬虫课程...
廖雪峰老师的Python商业爬虫课程 Python网络爬虫实战教程体会不一样的Python爬虫课程 1.JPG (53.51 KB, 下载次数: 1) 2019-8-9 08:15 上传 2.JPG ...
python网络爬虫系列教程_Python网络爬虫系列教程连载 ----长期更新中，敬请关注!...
感谢大家长期对Python爱好者社区的支持,后期Python爱好者社区推出Python网络爬虫系列教程.欢迎大家关注.以下系列教程大纲,欢迎大家补充.视频长期连载更新中 --------------- ...
Python Scrapy 爬虫 - 爬取多级别的页面
Python Scrapy 爬虫 - 爬取多级别的页面互联网中众多的 scrapy 教程模板,都是爬取下一页 → \rightarrow →下一页形式的,很少有父级 → \rightarrow ...
Python Scrapy 爬虫框架爬取推特信息及数据持久化！整理了我三天！
最近要做一个国内外新冠疫情的热点信息的收集系统,所以,需要爬取推特上的一些数据,然后做数据分类及情绪分析.作为一名合格的程序员,我们要有「拿来主义精神」,借助别人的轮子来实现自己的项目,而不是从头搭建 ...
python爱心代码简单教程
python爱心代码简单教程操作方法 1 将以上代码保存为.py文件,假设保存的文件名为 love.py (不会保存?先保存为txt文本,然后将后缀改为.py) 2 在终端(cmd命令窗口)输入pyt ...

Python Scrapy 爬虫简单教程

导览

1. Scrapy install

准备知识

Windows安装 Scrapy

Linux安装 Scrapy

2. Scrapy 项目创建

3. Scrapy 自定义爬虫类

4. Scrapy 处理逻辑

本文代码结果展示：

5. Scrapy 扩展

Xpath:

Css:

Python Scrapy 爬虫简单教程相关推荐

最新文章

热门文章