Source Code for Module zeroinstall.injector._download_child

  1  # Copyright (C) 2011, Thomas Leonard 
  2  # See the README file for details, or visit http://0install.net. 
  3   
  4  import sys, os, socket, ssl 
  5   
  6  from zeroinstall import _ 
  7  from zeroinstall.injector import download 
  8  from zeroinstall.support import ssl_match_hostname 
  9   
 10  if sys.version_info[0] > 2: 
 11          from urllib import request as urllib2 
 12          from http.client import HTTPSConnection, HTTPException 
 13  else: 
 14          import urllib2 
 15          from httplib import HTTPSConnection, HTTPException 
 16   
 17  try: 
 18          # http://pypi.python.org/pypi/certifi 
 19          import certifi 
 20          _fallback_ca_bundle = certifi.where() 
 21  except: 
 22          # Final fallback (last known signer of keylookup) 
 23          _fallback_ca_bundle = os.path.join(os.path.dirname(__file__), "EquifaxSecureCA.crt") 
 24   
 25  # Note: on MacOS X at least, it will also look in the system keychain provided that you supply *some* CAs. 
 26  # (if you don't specify any trusted CAs, Python trusts everything!) 
 27  # So, the "fallback" option doesn't necessarily mean that other sites won't work. 
 28  for ca_bundle in [ 
 29                  "/etc/ssl/certs/ca-certificates.crt",   # Debian/Ubuntu/Arch Linux 
 30                  "/etc/pki/tls/certs/ca-bundle.crt",     # Fedora/RHEL 
 31                  "/etc/ssl/ca-bundle.pem",               # openSUSE/SLE (claimed) 
 32                  "/var/lib/ca-certificates/ca-bundle.pem.new", # openSUSE (actual) 
 33                  _fallback_ca_bundle]: 
 34          if os.path.exists(ca_bundle): 
 35 -                class ValidatingHTTPSConnection(HTTPSConnection): 
 36 -                        def connect(self): 
 37                                  sock = socket.create_connection((self.host, self.port), self.timeout) 
 38                                  if hasattr(self, '_tunnel_host') and self._tunnel_host: 
 39                                          self.sock = sock 
 40                                          self._tunnel() 
 41                                  sock = ssl.wrap_socket(sock, cert_reqs = ssl.CERT_REQUIRED, ca_certs = ca_bundle) 
 42                                  ssl_match_hostname.match_hostname(sock.getpeercert(), self.host) 
 43                                  self.sock = sock 
 44   
 45 -                class ValidatingHTTPSHandler(urllib2.HTTPSHandler): 
 46 -                        def https_open(self, req): 
 47                                  return self.do_open(self.getConnection, req) 
 48   
 49 -                        def getConnection(self, host, timeout=300): 
 50                                  """@type host: str""" 
 51                                  return ValidatingHTTPSConnection(host) 
 52                  MyHTTPSHandler = ValidatingHTTPSHandler 
 53                  break 
 54  else: 
 55          raise Exception("No root CA's found (not even the built-in one!); security of HTTPS connections cannot be verified") 
 56   
 57 -class Redirect(Exception): 
 58 -        def __init__(self, req): 
 59                  Exception.__init__(self, "Redirect") 
 60                  self.req = req 
 61   
 62 -class MyRedirectHandler(urllib2.HTTPRedirectHandler): 
 63          """Throw an exception on redirects instead of continuing. The redirect will be handled in the main thread 
 64          so it can work with connection pooling.""" 
 65 -        def redirect_request(self, req, fp, code, msg, headers, newurl): 
 66                  """@type code: int 
 67                  @type msg: str 
 68                  @type newurl: str""" 
 69                  new_req = urllib2.HTTPRedirectHandler.redirect_request(self, req, fp, code, msg, headers, newurl) 
 70                  if new_req: 
 71                          raise Redirect(new_req) 
 72   
 73  # Our handler differs from the Python default in that: 
 74  # - we don't support file:// URLs 
 75  # - we don't follow HTTP redirects 
 76  _my_urlopen = urllib2.OpenerDirector() 
 77  for klass in [urllib2.ProxyHandler, urllib2.UnknownHandler, urllib2.HTTPHandler, 
 78                         urllib2.HTTPDefaultErrorHandler, MyRedirectHandler, 
 79                         urllib2.FTPHandler, urllib2.HTTPErrorProcessor, MyHTTPSHandler]: 
 80          _my_urlopen.add_handler(klass()) 
 81   
 82 -def download_in_thread(url, target_file, if_modified_since, notify_done): 
 83          """@type url: str 
 84          @type target_file: file""" 
 85          src = None 
 86          try: 
 87                  #print "Child downloading", url 
 88                  if url.startswith('http:') or url.startswith('https:') or url.startswith('ftp:'): 
 89                          req = urllib2.Request(url) 
 90                          if url.startswith('http:') and if_modified_since: 
 91                                  req.add_header('If-Modified-Since', if_modified_since) 
 92                          src = _my_urlopen.open(req) 
 93                  else: 
 94                          raise Exception(_('Unsupported URL protocol in: %s') % url) 
 95   
 96                  if sys.version_info[0] > 2: 
 97                          sock_recv = src.fp.read1                # Python 3 
 98                  else: 
 99                          try: 
100                                  sock_recv = src.fp._sock.recv   # Python 2 
101                          except AttributeError: 
102                                  sock_recv = src.fp.fp._sock.recv        # Python 2.5 on FreeBSD 
103                  while True: 
104                          data = sock_recv(256) 
105                          if not data: break 
106                          target_file.write(data) 
107                          target_file.flush() 
108   
109                  notify_done(download.RESULT_OK) 
110          except (urllib2.HTTPError, urllib2.URLError, HTTPException, socket.error) as ex: 
111                  if isinstance(ex, urllib2.HTTPError) and ex.code == 304: # Not modified 
112                          notify_done(download.RESULT_NOT_MODIFIED) 
113                  else: 
114                          #print >>sys.stderr, "Error downloading '" + url + "': " + (str(ex) or str(ex.__class__.__name__)) 
115                          __, ex, tb = sys.exc_info() 
116                          notify_done(download.RESULT_FAILED, (download.DownloadError(_('Error downloading {url}: {ex}').format(url = url, ex = ex)), tb)) 
117          except Redirect as ex: 
118                  notify_done(download.RESULT_REDIRECT, redirect = ex.req.get_full_url()) 
119          except Exception as ex: 
120                  __, ex, tb = sys.exc_info() 
121                  notify_done(download.RESULT_FAILED, (ex, tb)) 
122          finally: 
123                  if src is not None: 
124                          src.close() 
125