0alias

   1 #!/usr/bin/env python
   2 import os, sys
   3 from optparse import OptionParser
   4
   5 from zeroinstall.injector import reader, model, basedir
   6 from zeroinstall import support, alias, helpers
   7
   8 def export(name, value):
   9         """Try to guess the command to set an environment variable."""
  10         shell = os.environ.get('SHELL', '?')
  11         if 'csh' in shell:
  12                 return "setenv %s %s" % (name, value)
  13         return "export %s=%s" % (name, value)
  14
  15 def find_path(paths):
  16         """Find the first writable path in : separated list."""
  17         for path in paths:
  18                 if os.path.realpath(path).startswith(basedir.xdg_cache_home):
  19                         pass # print "Skipping cache", first_path
  20                 elif not os.access(path, os.W_OK):
  21                         pass # print "No access", first_path
  22                 else:
  23                         break
  24         else:
  25                 return None
  26
  27         return path
  28
  29 # Do this here so we can include it in the help message.
  30 # But, don't abort if there isn't one because we might
  31 # be doing something else (e.g. --manpage)
  32 first_path = find_path(os.environ['PATH'].split(':'))
  33
  34 parser = OptionParser(usage="usage: %%prog [options] alias [interface [command]]\n\n"
  35                 "Creates a script in the first usable directory in $PATH\n"
  36                 "(%s) to run 'interface' unless overridden by --dir.\n"
  37                 "If no interface is given, edits the policy for an existing alias.\n"
  38                 "For interfaces providing more than one command, the desired command\n"
  39                 "may also be given." % first_path)
  40 parser.add_option("-m", "--manpage", help="show the manual page for an existing alias", action='store_true')
  41 parser.add_option("-r", "--resolve", help="show the URI for an alias", action='store_true')
  42 parser.add_option("-V", "--version", help="display version information", action='store_true')
  43 parser.add_option("-d", "--dir", help="install in DIR", dest="user_path", metavar="DIR")
  44 parser.disable_interspersed_args()
  45
  46 (options, args) = parser.parse_args()
  47
  48 if options.version:
  49         import zeroinstall
  50         print "0alias (zero-install) " + zeroinstall.version
  51         print "Copyright (C) 2007 Thomas Leonard"
  52         print "This program comes with ABSOLUTELY NO WARRANTY,"
  53         print "to the extent permitted by law."
  54         print "You may redistribute copies of this program"
  55         print "under the terms of the GNU Lesser General Public License."
  56         print "For more information about these matters, see the file named COPYING."
  57         sys.exit(0)
  58
  59 if options.manpage:
  60         if len(args) != 1:
  61                 os.execlp('man', 'man', *args)
  62                 sys.exit(1)
  63
  64 if len(args) < 1 or len(args) > 3:
  65         parser.print_help()
  66         sys.exit(1)
  67 alias_prog, interface_uri, main = (list(args) + [None, None])[:3]
  68
  69 if options.resolve or options.manpage:
  70         if interface_uri is not None:
  71                 parser.print_help()
  72                 sys.exit(1)
  73
  74 if options.user_path:
  75         first_path = options.user_path
  76         if not os.path.isdir(first_path):
  77                 print >>sys.stderr, "Directory '%s' does not exist." % first_path
  78                 sys.exit(1)
  79
  80 if interface_uri is None:
  81         try:
  82                 if not os.path.isabs(alias_prog):
  83                         full_path = support.find_in_path(alias_prog)
  84                         if not full_path:
  85                                 raise alias.NotAnAliasScript("Not found in $PATH: " + alias_prog)
  86                 else:
  87                         full_path = alias_prog
  88
  89                 interface_uri, main = alias.parse_script(full_path)
  90         except alias.NotAnAliasScript, ex:
  91                 if options.manpage:
  92                         os.execlp('man', 'man', *args)
  93                 print >>sys.stderr, str(ex)
  94                 sys.exit(1)
  95
  96 interface_uri = model.canonical_iface_uri(interface_uri)
  97
  98 if options.resolve:
  99         print interface_uri
 100         sys.exit(0)
 101
 102 if options.manpage:
 103         sels = helpers.ensure_cached(interface_uri)
 104         if not sels:
 105                 # Cancelled by user
 106                 sys.exit(1)
 107
 108         selected_impl = sels.selections[interface_uri]
 109         if selected_impl.id.startswith('/'):
 110                 impl_path = selected_impl.id
 111         else:
 112                 from zeroinstall.injector.iface_cache import iface_cache
 113                 impl_path = iface_cache.stores.lookup(selected_impl.id)
 114
 115         if main is None:
 116                 main = selected_impl.main
 117                 if main is None:
 118                         print >>sys.stderr, "No main program for interface '%s'" % interface_uri
 119                         sys.exit(1)
 120
 121         # TODO: the feed should say where the man-page is, but for now we'll just search
 122         # the whole implementation for one
 123
 124         prog_name = os.path.basename(main)
 125         alias_name = os.path.basename(args[0])
 126
 127         assert impl_path
 128         manpages = []
 129         for root, dirs, files in os.walk(impl_path):
 130                 for f in files:
 131                         if f.endswith('.gz'):
 132                                 manpage_file = f[:-3]
 133                         else:
 134                                 manpage_file = f
 135                         if manpage_file.endswith('.1') or \
 136                            manpage_file.endswith('.6') or \
 137                            manpage_file.endswith('.8'):
 138                                 manpage_prog = manpage_file[:-2]
 139                                 if manpage_prog == prog_name or manpage_prog == alias_name:
 140                                         os.execlp('man', 'man', os.path.join(root, f))
 141                                         sys.exit(1)
 142                                 else:
 143                                         manpages.append((root, f))
 144
 145         print "No matching manpage was found for '%s' (%s)" % (alias_name, interface_uri)
 146         if manpages:
 147                 print "These non-matching man-pages were found, however:"
 148                 for root, file in manpages:
 149                         print os.path.join(root, file)
 150         sys.exit(1)
 151
 152 if first_path is None:
 153         print >>sys.stderr, ("No writable non-cache directory in $PATH, which currently contains:\n\n%s\n\n"
 154                              "To create a directory for your scripts, use these commands:\n"
 155                              "$ mkdir ~/bin\n"
 156                              "$ %s\n"
 157                              "or specify a writable path with --path"
 158                              % ('\n'.join(os.environ['PATH'].split(':')), export('PATH', '$HOME/bin:$PATH')))
 159         sys.exit(1)
 160
 161 if len(args) == 1:
 162         os.execlp('0launch', '0launch', '-gd', '--', interface_uri)
 163         sys.exit(1)
 164
 165 try:
 166         interface = model.Interface(interface_uri)
 167         if not reader.update_from_cache(interface):
 168                 print >>sys.stderr, "Interface '%s' not currently in cache. Fetching..." % interface_uri
 169                 if os.spawnlp(os.P_WAIT, '0launch', '0launch', '-d', interface_uri):
 170                         raise model.SafeException("0launch failed")
 171                 if not reader.update_from_cache(interface):
 172                         raise model.SafeException("Interface still not in cache. Aborting.")
 173
 174         script = os.path.join(first_path, alias_prog)
 175         if os.path.exists(script):
 176                 raise model.SafeException("File '%s' already exists. Delete it first." % script)
 177                 sys.exit(1)
 178 except model.SafeException, ex:
 179         print >>sys.stderr, ex
 180         sys.exit(1)
 181
 182 wrapper = file(script, 'w')
 183 alias.write_script(wrapper, interface_uri, main)
 184
 185 # Make new script executable
 186 os.chmod(script, 0111 | os.fstat(wrapper.fileno()).st_mode)
 187 wrapper.close()
 188
 189 print "Created script '%s'." % script
 190 print "To edit policy: 0alias %s" % alias_prog
 191 print "(note: some shells require you to type 'rehash' now)"