                        課程
                    
                        /后端開發(fā)
                        
                            /Python
                        
                        /Python開發(fā)簡單爬蟲

代碼對了好幾遍，沒有發(fā)現(xiàn)什么錯誤，但是控制臺什么也沒有輸出，求高手指點

# coding =utf-8
from package3 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.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 = count + 1
??????????? except:
??????????????? print('craw failed')
??????? self.outputer.output_html()

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

# coding =utf-8
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 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
?? ?
?? ?
?? ?# coding =utf-8
from bs4 import BeautifulSoup
import re
import urlparse

class HtmlParser(object):
?? ?
?? ?
??? def _get_new_urls(self, page_url, soup):
??????? new_urls=set()
??????? # /view/123.htm
??????? links=soup.find_all('a',href=re.compile(r"/view/\d+\.htm"))
??????? 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
?? ?
?? ?
?? ?
?? ?
??? 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
?? ?
?? ?

# 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('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'])
??????????? fout.write("<td>%s</td>" % data['title'].encode('utf-8'))
??????????? fout.write("<td>%s</td>" % data['summary'].encode('utf-8'))
??????? fout.write('</table')
??????? fout.write('</body>')
??????? fout.write('</html>')
??????? fout.close()

# coding =utf-8
from pip._vendor.requests.models import Response
import urllib2

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

?? ?