Python--我的第一个爬虫

爬取百度百科python字条相关1000个数据

module:spider_main:

# coding:utf-8
from Baike_spider import url_manager, html_downloader, html_parser, \
    html_outputer


class SpiderMain(object):

    def __init__(self):
        self.urls = url_manager.UrlManager()
        self.downloader = html_downloader.HtmlDownloader()
        self.parser = html_parser.HtmlParse()
        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)
                count = count + 1;
            except:
                 print 'craw failed'   
            
            if(count == 10):
                break
        
        self.outputer.output_html()

if __name__ == "__main__":
    root_url = "https://baike.baidu.com/item/Python/407313?fr=aladdin#1"
    obj_spider = SpiderMain()
    obj_spider.craw(root_url)
    

module:html_downloader:

# coding:utf-8

import urllib2

class HtmlDownloader(object):
    
    def download(self, url):
        if url is None:
            return None
        
        response = urllib2.urlopen(url)
        if response.getcode() != 200:
            return None
        return response.read()    

 

module:html_outputer:

# coding:utf-8
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('output2.html', 'w')
        fout.write("")
        fout.write("")
        fout.write("")
        for data in self.datas:
            fout.write("")
            fout.write("" % data['url'])
            fout.write("" % data['title'].encode('utf-8'))
            fout.write("" % data['summary'].encode('utf-8'))
            fout.write("")
        fout.write("
%s
%s
%s
")
        fout.write("")
        fout.write("")

 

module:html_parser:

# coding:utf-8
from bs4 import BeautifulSoup
import  re
import urlparse
from test.inspect_fodder import Tit

class HtmlParse(object):
    
# href="/item/%E9%98%BF%E5%A7%86%E6%96%AF%E7%89%B9%E4%B8%B9/2259975"
    def _get_new_urls(self, page_url, soup):
        new_urls = set()
        links = soup.find_all('a', href=re.compile(r"/item/.+"))
        for link in links:
            new_url = link['href']
            new_full_url = urlparse.urljoin(page_url, new_url)
            new_urls.add(new_full_url)
        return new_urls

#    

#    
Python
# 


    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
    

    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
        

module:url_manager:

class UrlManager(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