发起一个开源项目http://www.abelkhan.com/
目前而言，已经用python编写了一个网络爬虫抓取页面，和一个简单的前端
网络爬虫，已经有很多高手写过，我基本上奉行了拿来主义，
得益于python完善的lib，这个网络爬虫实现起来非常的简单:
使用urllib2从对应的url地址抓取html
def get_page(url):
try:
headers = {‘User-Agent‘:‘Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebkit/537.36 (KHTML, like Gecko) Chrome/42.0.2311.135 Safari/537.36 Edge/12.10240‘,
‘Connection‘:‘Keep-Alive‘,
‘Accept‘:‘text/html, application/xhtml+xml, image/jxr, */*‘,
‘Accept-Language‘:‘zh-Hans-CN,zh-Hans;q=0.8,en-US;q=0.5,en;q=0.3‘,
}
cookie_jar = cookielib.CookieJar()
opener = urllib2.build_opener(urllib2.HTTPCookieProcessor(cookie_jar))
req = urllib2.Request(url = url, headers = headers)
response = opener.open(req, timeout = 5)
the_page = response.read()
headers = response.info()
return the_page, headers
except:
import traceback
traceback.print_exc()一个需要注意的地方是，有部分网站会限制爬虫访问，所以我加入了headers用于模拟浏览器访问。
这个方法差强人意，但是我也没有找到一个更完善的办法。
抓取到页面后，基于HTMLParser做了html的解析:
class htmlprocess(HTMLParser.HTMLParser):
def __init__(self, urlinfo):
HTMLParser.HTMLParser.__init__(self)
self.urllist = {}
self.sub_url = ""
self.urlinfo = urlinfo
self.current_url = urlinfo[‘url‘]
keywords = doclex.simplesplit(self.current_url)
for key in keywords:
if key != "com" and key != "www" and key != "cn":
self.urlinfo[‘keys‘][‘1‘].append(key)
self.current_tag = ""
self.style = ""
def handle_starttag(self, tag, attrs):
self.current_tag = tag
self.style = ‘None‘
self.sub_url = ""
if tag == ‘meta‘:
for name,value in attrs:
if name == ‘name‘:
if value == ‘keywords‘ or value == ‘metaKeywords‘:
self.style = ‘keywords‘
elif value == ‘description‘ or value == ‘metaDescription‘:
self.style = ‘profile‘
for name,value in attrs:
if name == ‘content‘:
if self.style == ‘keywords‘:
keywords = doclex.simplesplit(value)
if isinstance(keywords, list):
for key in keywords:
self.urlinfo[‘keys‘][‘1‘].append(key)
elif self.style == ‘profile‘:
self.urlinfo[‘profile‘][‘0‘] = value
encodingdate = chardet.detect(value)
if encodingdate[‘encoding‘]:
udata = unicode(value, encodingdate[‘encoding‘])
tlen = 16
if len(udata) < 16:
tlen = len(udata)
self.urlinfo[‘titlegen‘].append(udata[0:tlen].encode(‘utf-8‘))
else:
self.urlinfo[‘titlegen‘].append(value)
if tag == ‘a‘ or tag == ‘A‘ or tag == ‘link‘:
self.sub_url = ""
for name,value in attrs:
if name == ‘href‘:
if len(value) == 0:
return
if not judged_url(value):
if self.current_url[len(self.current_url) - 1] != ‘/‘ and value[0] != ‘/‘:
value = self.current_url + ‘/‘ + value
else:
value = self.current_url + value
if value.find(‘javascript‘) != -1:
return
if value.find(‘javaScript‘) != -1:
return
if self.current_url.find("apple") != -1:
if value.find("http://www.apple.com/cn/mac#ac-gn-menustate") !=-1:
return
if self.current_url.find("cnblogs") != -1:
if value.find("http://msg.cnblogs.com/send?recipient=itwriter") != -1:
return
elif value.find("http://i.cnblogs.com/EditPosts.aspx?opt=1") != -1:
return
elif value.find("http://i.cnblogs.com/EditPosts.aspx?postid=1935371") != -1:
return
elif value.find("http://msg.cnblogs.com/send?recipient=itwriter/") != -1:
return
elif value.find("http://msg.cnblogs.com/send?recipient=itwriter/GetUsername.aspx") != -1:
return
elif value.find("/EnterMyBlog.aspx?NewArticle=1") != -1:
return
elif value.find("GetUsername") != -1:
return
elif value.find("GetMyPassword") != -1:
return
elif value.find("http://i.cnblogs.com/EditPosts.aspx?postid=") != -1:
return
elif value[len(value) - 1] == ‘#‘:
value = value[0:-1]
if self.current_url.find(value) != -1:
return
if value[len(value) - 1] == ‘#‘:
value = value[0:-1]
if value != self.current_url and len(value) < 64 and not ingoreurl(value):
self.urllist[value] = {‘url‘:value, ‘keys‘:{‘1‘:[], ‘2‘:[], ‘3‘:[]}, ‘title‘:‘‘, ‘titlegen‘:[], ‘profile‘:{‘0‘:‘‘, ‘1‘:‘‘, ‘2‘:[]}}
self.sub_url = value
print value
def handle_data(self, data):
if self.current_tag == ‘title‘:
try:
data = doclex.delspace(data)
keys = doclex.lex(data)
if isinstance(keys, list) and len(keys) > 0:
for key in keys:
self.urlinfo[‘keys‘][‘2‘].append(key)
if len(data) > 0:
self.urlinfo[‘title‘] = data
except:
import traceback
traceback.print_exc()
elif self.current_tag == ‘a‘:
try:
if self.sub_url != "":
keys = doclex.simplesplit(data)
if isinstance(keys, list) and len(keys) > 0:
for key in keys:
if key in self.urllist[self.sub_url][‘keys‘][‘3‘]:
self.urllist[self.sub_url][‘keys‘][‘3‘].remove(key)
if key not in self.urllist[self.sub_url][‘keys‘][‘1‘] and key not in self.urllist[self.sub_url][‘keys‘][‘2‘]:
self.urllist[self.sub_url][‘keys‘][‘2‘].append(key)
encodingdate = chardet.detect(data)
if encodingdate[‘encoding‘]:
udata = unicode(data, encodingdate[‘encoding‘])
tlen = 16
if len(udata) < 16:
tlen = len(udata)
self.urllist[self.sub_url][‘titlegen‘].append(udata[0:tlen].encode(‘utf-8‘))
if len(udata) > 16:
self.urllist[self.sub_url][‘profile‘][‘1‘] = udata[0:32].encode(‘utf-8‘)
except:
import traceback
traceback.print_exc()
else:
try:
if not doclex.invialddata(data):
data = doclex.delspace(data)
encodingdate = chardet.detect(data)
udata = unicode(data, encodingdate[‘encoding‘])
tlen = 16
if len(udata) < 16:
tlen = len(udata)
self.urlinfo[‘titlegen‘].append(udata[0:tlen].encode(‘utf-8‘))
if len(udata) > 32:
self.urlinfo[‘profile‘][‘2‘].append((udata[0:32] + u"...").encode(‘utf-8‘))
keys1 = doclex.lex(data)
for key in keys1:
self.urlinfo[‘keys‘][‘3‘].append(key)
except:
import traceback
traceback.print_exc()基本上，要说的就是HTMLParser使用方法见文档，HTMLParser预先了定义了一组虚接口handle_starttag，handle_data和handle_endtag，使用者通过重载这三个接口，来实现对html中的tag进行处理，进而完整的解析抓取到的html。
然后从搜索结果来看，搜索的质量还很不尽如人意，欢迎大家的参与和提出意见
向我们提出意见:http://www.abelkhan.com/guestbook/
对项目进行捐助:http://www.abelkhan.com/collection/
代码托管地址如下:https://github.com/qianqians/websearch欢迎大家参与
本文出自 “11385076” 博客，请务必保留此出处http://11395076.blog.51cto.com/11385076/1758165
原文地址：http://11395076.blog.51cto.com/11385076/1758165
