0alias

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