archive.py

   1 from xml.dom import minidom
   2 from zeroinstall import SafeException
   3 from zeroinstall.zerostore import manifest
   4 try:
   5         from zeroinstall.zerostore import unpack
   6 except ImportError:
   7         # Older versions don't have it
   8         import unpack
   9 from zeroinstall.injector import namespaces
  10 import os, shutil, tempfile
  11
  12 import digest
  13 import xmltools
  14
  15 def ro_rmtree(root):
  16         """Like shutil.rmtree, except that we also delete with read-only items.
  17         @param root: the root of the subtree to remove
  18         @type root: str
  19         @since: 0.28"""
  20         for main, dirs, files in os.walk(root):
  21                 os.chmod(main, 0700)
  22         shutil.rmtree(root)
  23
  24 def manifest_for_dir(dir, alg):
  25         if alg == 'sha1':
  26                 # (for older versions of the injector)
  27                 import sha
  28                 class SHA1:
  29                         def new_digest(self): return sha.new()
  30                         def generate_manifest(self, dir): return manifest.generate_manifest(dir)
  31                         def getID(self, digest): return 'sha1=' + digest.hexdigest()
  32                 algorithm = SHA1()
  33         else:
  34                 algorithm = manifest.get_algorithm(alg)
  35
  36         digest = algorithm.new_digest()
  37         for line in algorithm.generate_manifest(dir):
  38                 digest.update(line + '\n')
  39         return algorithm.getID(digest)
  40
  41 def autopackage_get_start_offset(package):
  42         for line in file(package):
  43                 if line.startswith('export dataSize=') or line.startswith('export data_size='):
  44                         return os.path.getsize(package) - int(line.split('"', 2)[1])
  45         raise Exception("Can't find payload in autopackage (missing 'dataSize')")
  46
  47 def add_archive(data, url, local_file, extract, algs):
  48         if local_file is None:
  49                 local_file = os.path.abspath(os.path.basename(url))
  50                 if not os.path.exists(local_file):
  51                         raise SafeException("Use --archive-file option to specify a local copy of the archive "
  52                                         "(default file '%s' does not exist)" % local_file)
  53
  54         doc = minidom.parseString(data)
  55
  56         assert algs
  57
  58         if local_file.endswith('.package'):
  59                 start_offset = autopackage_get_start_offset(local_file)
  60                 type = 'application/x-bzip-compressed-tar'
  61         else:
  62                 start_offset = 0
  63                 type = None
  64
  65         all_impls = doc.documentElement.getElementsByTagNameNS(namespaces.XMLNS_IFACE, 'implementation')
  66         tmpdir = tempfile.mkdtemp('-0publish')
  67         try:
  68                 if start_offset or type:
  69                         unpack.unpack_archive(url, file(local_file), tmpdir, extract, start_offset = start_offset, type = type)
  70                 else:
  71                         unpack.unpack_archive(url, file(local_file), tmpdir, extract)
  72                 if extract:
  73                         extracted = os.path.join(tmpdir, extract)
  74                 else:
  75                         extracted = tmpdir
  76
  77                 archive_id = manifest_for_dir(extracted, algs[0])
  78                 extra_digests = set([manifest_for_dir(extracted, a) for a in algs[1:]])
  79
  80                 if '=' not in archive_id:
  81                         # New-style digests can't go in the ID
  82                         extra_digests.add(archive_id)
  83         finally:
  84                 ro_rmtree(tmpdir)
  85
  86         local_ifaces = []
  87         for impl in all_impls:
  88                 this_id = impl.getAttribute('id')
  89                 if this_id == archive_id:
  90                         break
  91                 if this_id.startswith('/') or this_id.startswith('.'):
  92                         local_ifaces.append(impl)
  93         else:
  94                 if len(local_ifaces) == 0:
  95                         raise Exception('Nothing with id "%s", and no local implementations' % archive_id)
  96                 if len(local_ifaces) > 1:
  97                         raise Exception('Nothing with id "%s", and multiple local implementations!' % archive_id)
  98                 impl = local_ifaces[0]
  99                 impl.setAttribute('id', archive_id)
 100
 101         assert impl.getAttribute('id') == archive_id
 102
 103         archive = xmltools.create_element(impl, 'archive')
 104         archive.setAttribute('href', url)
 105         archive.setAttribute('size', str(os.stat(local_file).st_size - start_offset))
 106         if extract is not None:
 107                 archive.setAttribute('extract', extract)
 108         if start_offset:
 109                 archive.setAttribute('start-offset', str(start_offset))
 110         if type:
 111                 archive.setAttribute('type', type)
 112
 113         # Remove digests we already
 114         for x in xmltools.children(impl, 'manifest-digest'):
 115                 digest_element = x
 116                 break
 117         else:
 118                 digest_element = doc.createElementNS(namespaces.XMLNS_IFACE, 'manifest-digest')
 119                 xmltools.insert_before(digest_element, archive)
 120         for x in extra_digests - set([digest.digests(impl)]):
 121                 for old_alg in ['sha1=', 'sha1new=', 'sha256=']:
 122                         if x.startswith(old_alg):
 123                                 name, value = x.split('=')
 124                                 break
 125                 else:
 126                         assert '_' in x, "Invalid digest %s" % x
 127                         name, value = x.split('_')
 128                 digest_element.setAttribute(name, value)
 129
 130         return doc.toxml('utf-8')