routefs/__init__.py

   1 import fuse
   2 import routes
   3 import errno
   4 import stat
   5
   6 fuse.fuse_python_api = (0, 2)
   7
   8 class RouteStat(fuse.Stat):
   9     def __init__(self):
  10         self.st_mode = 0
  11         self.st_ino = 0
  12         self.st_dev = 0
  13         self.st_nlink = 0
  14         self.st_uid = 0
  15         self.st_gid = 0
  16         self.st_size = 0
  17         self.st_atime = 0
  18         self.st_mtime = 0
  19         self.st_ctime = 0
  20
  21 class RouteMeta(type):
  22     def __init__(cls, classname, bases, dict_):
  23         super(RouteMeta, cls).__init__(classname, bases, dict_)
  24         if bases != (fuse.Fuse,):
  25             new_funcs = set(dict_.keys()).difference(dir(RouteFS))
  26             cls.controllers([func for func in new_funcs \
  27                                  if not func.startswith('_')])
  28
  29 class RouteFS(fuse.Fuse):
  30     __metaclass__ = RouteMeta
  31     def __init__(self, *args, **kwargs):
  32         super(RouteFS, self).__init__(*args, **kwargs)
  33
  34         self.map = self.make_map()
  35         self.map.create_regs(self.controller_list)
  36
  37     def make_map(self):
  38         m = routes.Mapper()
  39
  40         m.connect(':controller')
  41
  42         return m
  43
  44     @classmethod
  45     def controllers(cls, lst):
  46         cls.controller_list = lst
  47
  48     def _get_file(self, path):
  49         match = self.map.match(path)
  50         if match is None:
  51             return
  52         controller = match.pop('controller')
  53         result = getattr(self, controller)(**match)
  54         return result
  55
  56     def readdir(self, path, offset):
  57         obj = self._get_file(path)
  58         if type(obj) is not Directory:
  59             return
  60         else:
  61             for member in ['.', '..'] + obj:
  62                 yield fuse.Direntry(str(member))
  63
  64     def getattr(self, path):
  65         obj = self._get_file(path)
  66         if obj is None:
  67             return -errno.ENOENT
  68
  69         st = RouteStat()
  70         if type(obj) is Directory:
  71             st.st_mode = stat.S_IFDIR | 0755
  72             st.st_nlink = 2
  73         elif type(obj) is Symlink:
  74             st.st_mode = stat.S_IFLNK | 0777
  75             st.st_nlink = 1
  76             st.st_size = len(obj)
  77         else:
  78             st.st_mode = stat.S_IFREG | 0444
  79             st.st_nlink = 1
  80             st.st_size = len(obj)
  81
  82         return st
  83
  84     def read(self, path, length, offset):
  85         obj = self._get_file(path)
  86         if obj is None:
  87             return -errno.ENOENT
  88         elif type(obj) in (Directory, Symlink):
  89             return -errno.EINVAL
  90         else:
  91             return obj[offset:offset + length]
  92
  93     def readlink(self, path):
  94         obj = self._get_file(path)
  95         if type(obj) is not Symlink:
  96             return -errno.EINVAL
  97         else:
  98             return obj
  99
 100 class Directory(list):
 101     """
 102     A dummy class representing a filesystem entry that should be a
 103     directory
 104     """
 105     pass
 106
 107 class Symlink(str):
 108     """
 109     A dummy class representing something that should be a symlink
 110     """
 111     pass
 112
 113 def main(cls):
 114     server = cls(version="%prog " + fuse.__version__,
 115                  usage=fuse.Fuse.fusage,
 116                  dash_s_do='setsingle')
 117     server.parse(errex=1)
 118     server.main()