Maison > Article > développement back-end > Python réalise un projet d'agrégation de nouvelles
Cette fois, je vais vous présenter Python pour créer un projet d'agrégation de nouvelles. Quelles sont les précautions pour que Python crée un projet d'agrégation de nouvelles. Voici un cas pratique, jetons un coup d'œil.
Commençons par le code, puis analysons-le un par un :
from nntplib import NNTP from time import strftime,time,localtime from email import message_from_string from urllib import urlopen import textwrap import re day = 24*60*60 def wrap(string,max=70): ''' ''' return '\n'.join(textwrap.wrap(string)) + '\n' class NewsAgent: ''' ''' def init(self): self.sources = [] self.destinations = [] def addSource(self,source): self.sources.append(source) def addDestination(self,dest): self.destinations.append(dest) def distribute(self): items = [] for source in self.sources: items.extend(source.getItems()) for dest in self.destinations: dest.receiveItems(items) class NewsItem: def init(self,title,body): self.title = title self.body = body class NNTPSource: def init(self,servername,group,window): self.servername = servername self.group = group self.window = window def getItems(self): start = localtime(time() - self.window*day) date = strftime('%y%m%d',start) hour = strftime('%H%M%S',start) server = NNTP(self.servername) ids = server.newnews(self.group,date,hour)[1] for id in ids: lines = server.article(id)[3] message = message_from_string('\n'.join(lines)) title = message['subject'] body = message.get_payload() if message.is_multipart(): body = body[0] yield NewsItem(title,body) server.quit() class SimpleWebSource: def init(self,url,titlePattern,bodyPattern): self.url = url self.titlePattern = re.compile(titlePattern) self.bodyPattern = re.compile(bodyPattern) def getItems(self): text = urlopen(self.url).read() titles = self.titlePattern.findall(text) bodies = self.bodyPattern.findall(text) for title.body in zip(titles,bodies): yield NewsItem(title,wrap(body)) class PlainDestination: def receiveItems(self,items): for item in items: print item.title print '-'*len(item.title) print item.body class HTMLDestination: def init(self,filename): self.filename = filename def receiveItems(self,items): out = open(self.filename,'w') print >> out,''' <html> <head> <title>Today's News</title> </head> <body> <h1>Today's News</hi> ''' print >> out, '<ul>' id = 0 for item in items: id += 1 print >> out, '<li><a href="#" rel="external nofollow" >%s</a></li>' % (id,item.title) print >> out, '</ul>' id = 0 for item in items: id += 1 print >> out, '<h2><a name="%i">%s</a></h2>' % (id,item.title) print >> out, '<pre class="brush:php;toolbar:false">%s' % item.body print >> out, '''