Source Code for Module ndg.httpsclient.urllib2_build_opener

 1  """urllib2 style build opener integrates with HTTPSConnection class from this 
 2  package. 
 3  """ 
 4  __author__ = "P J Kershaw" 
 5  __date__ = "21/12/10" 
 6  __copyright__ = "(C) 2011 Science and Technology Facilities Council" 
 7  __license__ = "BSD - see LICENSE file in top-level directory" 
 8  __contact__ = "Philip.Kershaw@stfc.ac.uk" 
 9  __revision__ = '$Id$' 
10  import logging 
11  from urllib2 import (ProxyHandler, UnknownHandler, HTTPDefaultErrorHandler,  
12                       FTPHandler, FileHandler, HTTPErrorProcessor, HTTPHandler,  
13                       OpenerDirector, HTTPRedirectHandler) 
14   
15  from ndg.httpsclient.https import HTTPSContextHandler 
16   
17  log = logging.getLogger(__name__) 
18   
19   
20  # Copied from urllib2 with modifications for ssl 
21 -def build_opener(*handlers, **kw): 
22      """Create an opener object from a list of handlers. 
23   
24      The opener will use several default handlers, including support 
25      for HTTP and FTP. 
26   
27      If any of the handlers passed as arguments are subclasses of the 
28      default handlers, the default handlers will not be used. 
29      """ 
30      import types 
31      def isclass(obj): 
32          return isinstance(obj, types.ClassType) or hasattr(obj, "__bases__") 
33   
34      opener = OpenerDirector() 
35      default_classes = [ProxyHandler, UnknownHandler, HTTPHandler, 
36                         HTTPDefaultErrorHandler, HTTPRedirectHandler, 
37                         FTPHandler, FileHandler, HTTPErrorProcessor] 
38      check_classes = list(default_classes) 
39      check_classes.append(HTTPSContextHandler) 
40      skip = [] 
41      for klass in check_classes: 
42          for check in handlers: 
43              if isclass(check): 
44                  if issubclass(check, klass): 
45                      skip.append(klass) 
46              elif isinstance(check, klass): 
47                  skip.append(klass) 
48   
49      for klass in default_classes: 
50          if klass not in skip: 
51              opener.add_handler(klass()) 
52               
53      # Pick up SSL context from keyword settings 
54      ssl_context = kw.get('ssl_context') 
55       
56      # Add the HTTPS handler with ssl_context 
57      if HTTPSContextHandler not in skip: 
58          opener.add_handler(HTTPSContextHandler(ssl_context)) 
59   
60      for h in handlers: 
61          if isclass(h): 
62              h = h() 
63          opener.add_handler(h) 
64   
65      return opener 
66