zeroinstall/injector/_download_child.py

   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
   9 import urllib2, httplib
  10
  11 # This works on Debian. It probably needs to be updated to handle other platforms.
  12 ca_file = "/etc/ssl/certs/ca-certificates.crt"
  13
  14 if os.path.exists(ca_file):
  15         class ValidatingHTTPSConnection(httplib.HTTPSConnection):
  16                 def connect(self):
  17                         sock = socket.create_connection((self.host, self.port), self.timeout)
  18                         if self._tunnel_host:
  19                                 self.sock = sock
  20                                 self._tunnel()
  21                         self.sock = ssl.wrap_socket(sock, cert_reqs = ssl.CERT_REQUIRED, ca_certs = ca_file)
  22
  23         class ValidatingHTTPSHandler(urllib2.HTTPSHandler):
  24                 def https_open(self, req):
  25                         return self.do_open(self.getConnection, req)
  26
  27                 def getConnection(self, host, timeout=300):
  28                         return ValidatingHTTPSConnection(host)
  29
  30         urlopener = urllib2.build_opener(ValidatingHTTPSHandler)
  31
  32         # Builds an opener that overrides the default HTTPS handler with our one
  33         _my_urlopen = urllib2.build_opener(ValidatingHTTPSHandler()).open
  34 else:
  35         _my_urlopen = urllib2.urlopen
  36
  37 def download_in_thread(url, target_file, if_modified_since, notify_done):
  38         try:
  39                 #print "Child downloading", url
  40                 if url.startswith('http:') or url.startswith('https:') or url.startswith('ftp:'):
  41                         req = urllib2.Request(url)
  42                         if url.startswith('http:') and if_modified_since:
  43                                 req.add_header('If-Modified-Since', if_modified_since)
  44                         src = _my_urlopen(req)
  45                 else:
  46                         raise Exception(_('Unsupported URL protocol in: %s') % url)
  47
  48                 try:
  49                         sock = src.fp._sock
  50                 except AttributeError:
  51                         sock = src.fp.fp._sock  # Python 2.5 on FreeBSD
  52                 while True:
  53                         data = sock.recv(256)
  54                         if not data: break
  55                         target_file.write(data)
  56                         target_file.flush()
  57
  58                 notify_done(download.RESULT_OK)
  59         except (urllib2.HTTPError, urllib2.URLError, httplib.HTTPException) as ex:
  60                 if isinstance(ex, urllib2.HTTPError) and ex.code == 304: # Not modified
  61                         notify_done(download.RESULT_NOT_MODIFIED)
  62                 else:
  63                         #print >>sys.stderr, "Error downloading '" + url + "': " + (str(ex) or str(ex.__class__.__name__))
  64                         __, ex, tb = sys.exc_info()
  65                         notify_done(download.RESULT_FAILED, (download.DownloadError(unicode(ex)), tb))
  66         except Exception as ex:
  67                 __, ex, tb = sys.exc_info()
  68                 notify_done(download.RESULT_FAILED, (ex, tb))