python爬虫框架talonspider简单介绍

2020-01-04 17:18:11

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1.为什么写这个？

一些简单的页面，无需用比较大的框架来进行爬取，自己纯手写又比较麻烦

因此针对这个需求写了talonspider:

•1.针对单页面的item提取 - 具体介绍点这里
•2.spider模块 - 具体介绍点这里

2.介绍&&使用

2.1.item

这个模块是可以独立使用的，对于一些请求比较简单的网站（比如只需要get请求），单单只用这个模块就可以快速地编写出你想要的爬虫，比如(以下使用python3，python2见examples目录)：

2.1.1.单页面单目标

比如要获取这个网址http://book.qidian.com/info/1004608738 的书籍信息，封面等信息，可直接这样写：

import timefrom talonspider import Item, TextField, AttrFieldfrom pprint import pprintclass TestSpider(Item):  author = TextField(css_select='a.writer')  cover = AttrField(css_select='a#bookImg>img', attr='src')  def tal_title(self, title):    return title  def tal_cover(self, cover):    return 'http:' + coverif __name__ == '__main__':  item_data = TestSpider.get_item(url='http://book.qidian.com/info/1004608738')  pprint(item_data)

具体见qidian_details_by_item.py

2.1.1.单页面多目标

比如获取豆瓣250电影首页展示的25部电影，这一个页面有25个目标，可直接这样写：

from talonspider import Item, TextField, AttrFieldfrom pprint import pprint# 定义继承自item的爬虫类class DoubanSpider(Item):  target_item = TextField(css_select='div.item')  cover = AttrField(css_select='div.pic>a>img', attr='src')  abstract = TextField(css_select='span.inq')  def tal_title(self, title):    if isinstance(title, str):      return title    else:      return ''.join([i.text.strip().replace('/xa0', '') for i in title])if __name__ == '__main__':  items_data = DoubanSpider.get_items(url='https://movie.douban.com/top250')  result = []  for item in items_data:    result.append({      'title': item.title,      'cover': item.cover,      'abstract': item.abstract,    })  pprint(result)

具体见douban_page_by_item.py

2.2.spider

当需要爬取有层次的页面时，比如爬取豆瓣250全部电影，这时候spider部分就派上了用场：

# !/usr/bin/env pythonfrom talonspider import Spider, Item, TextField, AttrField, Requestfrom talonspider.utils import get_random_user_agent# 定义继承自item的爬虫类class DoubanItem(Item):  target_item = TextField(css_select='div.item')  cover = AttrField(css_select='div.pic>a>img', attr='src')  abstract = TextField(css_select='span.inq')  def tal_title(self, title):    if isinstance(title, str):      return title    else:      return ''.join([i.text.strip().replace('/xa0', '') for i in title])class DoubanSpider(Spider):  # 定义起始url，必须  start_urls = ['https://movie.douban.com/top250']  # requests配置  request_config = {    'RETRIES': 3,    'DELAY': 0,    'TIMEOUT': 20  }  # 解析函数 必须有  def parse(self, html):    # 将html转化为etree    etree = self.e_html(html)    # 提取目标值生成新的url    pages = [i.get('href') for i in etree.cssselect('.paginator>a')]    pages.insert(0, '?start=0&filter=')    headers = {      "User-Agent": get_random_user_agent()    }    for page in pages:      url = self.start_urls[0] + page      yield Request(url, request_config=self.request_config, headers=headers, callback=self.parse_item)  def parse_item(self, html):    items_data = DoubanItem.get_items(html=html)    # result = []    for item in items_data:      # result.append({      #   'title': item.title,      #   'cover': item.cover,      #   'abstract': item.abstract,      # })      # 保存      with open('douban250.txt', 'a+') as f:        f.writelines(item.title + '/n')if __name__ == '__main__':  DoubanSpider.start()

控制台：

/Users/howie/anaconda3/envs/work3/bin/python /Users/howie/Documents/programming/python/git/talonspider/examples/douban_page_by_spider.py2017-06-07 23:17:30,346 - talonspider - INFO: talonspider started2017-06-07 23:17:30,693 - talonspider_requests - INFO: GET a url: https://movie.douban.com/top2502017-06-07 23:17:31,074 - talonspider_requests - INFO: GET a url: https://movie.douban.com/top250?start=25&filter=2017-06-07 23:17:31,416 - talonspider_requests - INFO: GET a url: https://movie.douban.com/top250?start=50&filter=2017-06-07 23:17:31,853 - talonspider_requests - INFO: GET a url: https://movie.douban.com/top250?start=75&filter=2017-06-07 23:17:32,523 - talonspider_requests - INFO: GET a url: https://movie.douban.com/top250?start=100&filter=2017-06-07 23:17:33,032 - talonspider_requests - INFO: GET a url: https://movie.douban.com/top250?start=125&filter=2017-06-07 23:17:33,537 - talonspider_requests - INFO: GET a url: https://movie.douban.com/top250?start=150&filter=2017-06-07 23:17:33,990 - talonspider_requests - INFO: GET a url: https://movie.douban.com/top250?start=175&filter=2017-06-07 23:17:34,406 - talonspider_requests - INFO: GET a url: https://movie.douban.com/top250?start=200&filter=2017-06-07 23:17:34,787 - talonspider_requests - INFO: GET a url: https://movie.douban.com/top250?start=225&filter=2017-06-07 23:17:34,809 - talonspider - INFO: Time usage：0:00:04.462108Process finished with exit code 0

此时当前目录会生成douban250.txt，具体见douban_page_by_spider.py。

3.说明

学习之作，待完善的地方还有很多，欢迎提意见，项目地址talonspider。

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