- 编辑工具:vscode
- 运行环境:Mac OS X11
- python版本:3.5
Windows下我也试过,没问题。
安装:【虚拟环境安装】
- Linux和MacOS下,推荐使用virtualenvwrapper创建虚拟环境。不要用电脑自带的python。
- 终端安装:pip isntall scrapy
- 如果已经安装Anaconda,升级即可。
conda install -c conda-forge scrapy
命令行操作:scrapy shell
scrapy shell 'http://quotes.toscrape.com/page/1/'
scrapy shell "http://quotes.toscrape.com/page/1/"
【Windows必须用双引号。就是这么矫情。】
可以用来测试抓取数据的效果,实时得到反馈。运行之后是这种样子:
我安装了ipython,所以它直接进入ipython的shell的样子。没安装的话就是python三个大于号(>>>)的那个界面。像这样:
[ ... Scrapy log here ... ]
2016-09-19 12:09:27 [scrapy] DEBUG: Crawled (200) <GET http://quotes.toscrape.com/page/1/> (referer: None)
[s] Available Scrapy objects:
[s] scrapy scrapy module (contains scrapy.Request, scrapy.Selector, etc)
[s] crawler <scrapy.crawler.Crawler object at 0x7fa91d888c90>
[s] item {}
[s] request <GET http://quotes.toscrape.com/page/1/>
[s] response <200 http://quotes.toscrape.com/page/1/>
[s] settings <scrapy.settings.Settings object at 0x7fa91d888c10>
[s] spider <DefaultSpider 'default' at 0x7fa91c8af990>
[s] Useful shortcuts:
[s] shelp() Shell help (print this help)
[s] fetch(req_or_url) Fetch request (or URL) and update local objects
[s] view(response) View response in a browser
>>>
一个栗子
爬取百度贴吧帖子的标题、作者、回复数。
创建scrapy项目:
-
scrapy startproject tutorial
项目名字可以随便起。终端命令运行如下:目录结构是这样子的:
tutorial/ scrapy.cfg # deploy configuration file tutorial/ # project's Python module, you'll import your code from here __init__.py items.py # project items definition file pipelines.py # project pipelines file settings.py # project settings file spiders/ # a directory where you'll later put your spiders __init__.py
修改items.py
import scrapy
class TiebaItem(scrapy.Item):
# name = scrapy.Field()
title = scrapy.Field()
author = scrapy.Field()
comment_num = scrapy.Field()
编写爬虫程序: tieba.py
放在spider文件夹下。
from scrapy.spider import Spider
from scrapy.selector import Selector
from tutorial.items import TiebaItem
class TibaSpider(Spider):
name = "tieba"
allowed_domains = ['tieba.baidu.com'] # 域名列表
start_urls = [
'http://tieba.baidu.com/f?kw=%E7%BD%91%E7%BB%9C%E7%88%AC%E8%99%AB&ie=utf-8',
]
def parse(self, response):
#page = response.url.split("/")[-1]
#filename = 'tieba.baidu-%s.html' % page
#with open(filename, 'wb') as f:
# f.write(response.body)
#self.log('Saved file %s' % filename)
items = []
for sel in response.xpath('//li[@class=" j_thread_list clearfix"]'):
item = TiebaItem()
item['title'] = sel.xpath('./div/div[2]/div[1]/div[1]/a/text()').extract()
item['author'] = sel.xpath('.//span[@class="frs-author-name-wrap"]/a/text()').extract()
item['comment_num'] = sel.xpath('.//span[@class="threadlist_rep_num center_text"]/text()').extract()
items.append(item)
return items
这里用的是xpath,谷歌浏览器右键--检查--HTML代码右键copy--copy xpath。copy selector获得的是css结构。
在终端运行
scrapy crawl tieba -o items.json
运行爬虫程序,输出为json格式。也可以是其他格式比如txt、csv等等。
结果
成功提取到了标题、作者和回復數。json文件显示的是Unicode编码。
保存CSV格式就可以直接看到汉字。
这才是个最基础的scrapy项目,还在学习中。。。[围笑]
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