面向对象编程_书写规范

最新推荐文章于 2024-11-21 16:09:45 发布

原创最新推荐文章于 2024-11-21 16:09:45 发布 · 344 阅读

CC 4.0 BY-SA版权

训练自己的代码,书写规范.

1_ 调用函数:


import url_manager, html_downloader, html_parser, html_outputer

class SpiderMain:
    def __init__(self):
        self.urls = url_manager.UrlMamager()
        self.downloader = html_downloader.HtmlDownloader()
        self.parser = html_parser.HtmlParser()
        self.outputer = html_outputer.HtmlOutputer()

    def craw(self,root_url):
        count = 1
        self.urls.add_new_url(root_url)
        while self.urls.has_new_url():
            try:
                new_url = self.urls.get_new_url()
                print('craw %d : %s' % (count,new_url))
                html_cont = self.downloader.download(new_url)
                new_urls, new_data = self.parser.parse(new_url, html_cont)
                self.urls.add_new_urls(new_urls)
                self.outputer.collect_data(new_data)

                if count == 1000:
                    break
                count += 1
            except:
                print('craw failed')

        self.outputer.output_html()

if __name__ == '__main__':
    root_url = 'http://baike.baidu.com/view/21087.htm'
    obj_spider = SpiderMain()
    obj_spider.craw(root_url)

2_ url管理器:

class UrlMamager(object):
    def __init__(self):
        self.new_urls = set()
        self.old_urls = set()


    def add_new_url(self,url):
        if url is None:
            return
        if url not in self.new_urls and url not in self.old_urls:
            self.new_urls.add(url)

    def add_new_urls(self, urls):
        if urls is None or len(urls) == 0:
            return
        for url in urls:
            self.add_new_url(url)

    def has_new_url(self):
        return len(self.new_urls) != 0

    def get_new_url(self):
        new_url = self.new_urls.pop()
        self.old_urls.add(new_url)
        return new_url

3_ 网页下载器:

import urllib3

class HtmlDownloader(object):


    def download(self,url):
        if url is None:
            return None

        response = urllib3.urlopen(url)
        if response.getcode() != 200:
            return None

        return response.read()

4_ 网页分析器:

import re
from bs4 import BeautifulSoup

class HtmlParser(object):


    def parse(self, page_url, html_cont):
        if page_url is None or html_cont is None:
            return

        soup = BeautifulSoup(html_cont,'html.parser',from_encoding='utf-8')
        new_urls = self._get_new_urls(page_url,soup)
        new_data = self._get_new_data(page_url,soup)
        return new_urls,new_data

    def _get_new_urls(self, page_url, soup):
        new_urls = set()
        links = soup.find_all('a', href=re.compile(r"/view/\d+\.htm"))
        for link in links:
            new_url = link['href']
            new_full_url = str(page_url) + str(new_url)
            new_urls.add(new_full_url)
        return new_urls

    def _get_new_data(self, page_url, soup):
        res_data = {}
        res_data['url'] = page_url
        title_node = soup.find('dd',class_="lemmaWgt-lemmatitle-title").find("h1")
        res_data['title'] = title_node.get_text()
        summary_node = soup.find('div',class_="lemma-summary")
        res_data['summary'] = summary_node.get_text()
        return res_data

5_ 输出器:

class HtmlOutputer(object):
    def __init__(self):
        self.datas = []

    def collect_data(self, data):
        if data is None:
            return
        self.datas.append(data)

    def output_html(self):
        fout = open('output.html', 'w')

        fout.write('<html>')
        fout.write('<body>')
        fout.write('<table>')
        for data in self.datas:
            fout.write("<tr>")
            fout.write('<td>%s</td>' % data['url'].encode('utf-8'))
            fout.write('<td>%s</td>' % data['title'].encode('utf-8'))
            fout.write('<td>%s</td>' % data['summary'].encode('utf-8'))
            fout.write("</tr>")

        fout.write('</table>')
        fout.write('</body>')
        fout.write('</html>')