Add a dummy console for the console server's conserver in case no VMs
[invirt/packages/invirt-console.git] / files / usr / bin / sipb-xen-consolefs
index 380c94b..aa7d1ca 100755 (executable)
 #!/usr/bin/python
 
-import fuse
-from fuse import Fuse
+import routefs
+from routes import Mapper
 
+from syslog import *
 from time import time
 
-import stat    # for file properties
-import os        # for filesystem modes (O_RDONLY, etc)
-import errno   # for error number codes (ENOENT, etc)
-                          # - note: these must be returned as negatives
+import os
+import errno
 
-import sipb_xen_database
-
-fuse.fuse_python_api = (0, 2)
+from invirt.config import structs as config
+from invirt import database
 
 realpath = "/home/machines/"
 
-def dirFromList(list):
-       """
-       Return a properly formatted list of items suitable to a directory listing.
-       ['a', 'b', 'c'] => [('a', 0), ('b', 0), ('c', 0)]
-       """
-       return [(x, 0) for x in list]
-
-def getDepth(path):
-       """
-       Return the depth of a given path, zero-based from root ('/')
-       """
-       if path == '/':
-               return 0
-       else:
-               return path.count('/')
-
-def getParts(path):
-       """
-       Return the slash-separated parts of a given path as a list
-       """
-       if path == '/':
-               return ['/']
-       else:
-               return path[1:].split('/')
-
-class MyStat:
-       def __init__(self):
-               self.st_mode = 0
-               self.st_ino = 0
-               self.st_dev = 0
-               self.st_nlink = 0
-               self.st_uid = 0
-               self.st_gid = 0
-               self.st_size = 0
-               self.st_atime = 0
-               self.st_mtime = 0
-               self.st_ctime = 0
-       
-       def toTuple(self):
-               return (self.st_mode, self.st_ino, self.st_dev, self.st_nlink, self.st_uid, self.st_gid, self.st_size, self.st_atime, self.st_mtime, self.st_ctime)
-
-class ConsoleFS(Fuse):
+class ConsoleFS(routefs.RouteFS):
        """
+       ConsoleFS creates a series of subdirectories each mirroring the same real
+       directory, except for a single file - the .k5login - which is dynamically
+       generated for each subdirectory
        """
        
        def __init__(self, *args, **kw):
-               Fuse.__init__(self, *args, **kw)
+               """Initialize the filesystem and set it to allow_other access besides
+               the user who mounts the filesystem (i.e. root)
+               """
+               super(ConsoleFS, self).__init__(*args, **kw)
                self.lasttime = time()
-               self.allow_other = 1
-               print 'Init complete.'
-       
-       def mirrorPath(self, path):
-               return realpath + "/".join(getParts(path)[1:])
+               self.fuse_args.add("allow_other", True)
+               
+               openlog('sipb-xen-consolefs ', LOG_PID, LOG_DAEMON)
+               
+               syslog(LOG_DEBUG, 'Init complete.')
+
+       def make_map(self):
+               m = Mapper()
+               m.connect('', controller='getMachines')
+               m.connect(':machine', controller='getMirror')
+               m.connect(':machine/.k5login', controller='getK5login')
+               m.connect(':machine/*(path)', controller='getMirror')
+               return m
        
-       def getMachines(self):
+       def getMachines(self, **kw):
+               """Get the list of VMs in the database, clearing the cache if it's 
+               older than 15 seconds"""
                if time() - self.lasttime > 15:
                        self.lasttime = time()
-                       sipb_xen_database.clear_cache()
-               return [machine.name for machine in sipb_xen_database.Machine.select()]
+                       database.clear_cache()
+               return [machine.name for machine in database.Machine.query()]
        
-       def getUid(self, machine_name):
-               return sipb_xen_database.Machine.get_by(name=machine_name).machine_id + 1000
+       def getMirror(self, machine, path='', **kw):
+               """Translate the path into its realpath equivalent, and return that
+               """
+               real = realpath + path
+               if os.path.isdir(real):
+                       # The list is converted to a set so that we can handle the case 
+                       # where there is already a .k5login in the realpath gracefully    
+                       return routefs.Directory(set(os.listdir(real) + ['.k5login']))
+               elif os.path.islink(real):
+                       return routefs.Symlink(os.readlink(real))
+               elif os.path.isfile(real):
+                       return open(real).read()
+               else:
+                       return -errno.EINVAL
        
-       def getK5login(self, machine_name):
-               machine = sipb_xen_database.Machine.get_by(name=machine_name)
+       def getK5login(self, machine, **kw):
+               """Build the ACL for a machine and turn it into a .k5login file
+               """
+               machine = database.Machine.query().filter_by(name=machine).one()
                users = [acl.user for acl in machine.acl]
                return "\n".join(map(self.userToPrinc, users) + [''])
        
+       def mirrorPath(self, path):
+               """Translate a virtual path to its real path counterpart"""
+               return realpath + "/".join(getParts(path)[1:])
+       
        def userToPrinc(self, user):
+               """Convert Kerberos v4-style names to v5-style and append a default
+               realm if none is specified
+               """
                if '@' in user:
                        (princ, realm) = user.split('@')
                else:
                        princ = user
-                       realm = "ATHENA.MIT.EDU"
-               
-               return princ.replace('.', '/') + realm
-       
-       def getattr(self, path):
-               """
-               - st_mode (protection bits)
-               - st_ino (inode number)
-               - st_dev (device)
-               - st_nlink (number of hard links)
-               - st_uid (user ID of owner)
-               - st_gid (group ID of owner)
-               - st_size (size of file, in bytes)
-               - st_atime (time of most recent access)
-               - st_mtime (time of most recent content modification)
-               - st_ctime (platform dependent; time of most recent metadata change on Unix,
-                                       or the time of creation on Windows).
-               """
+                       realm = config.authn[0].realm
                
-               print "*** getattr: " + path
-               
-               depth = getDepth(path)
-               parts = getParts(path)
-               
-               st = MyStat()
-               if path == '/':
-                       st.st_mode = stat.S_IFDIR | 0755
-                       st.st_nlink = 2
-               elif depth == 1:
-                       if parts[-1] in self.getMachines():
-                               st.st_mode = stat.S_IFDIR | 0755
-                               st.st_nlink = 2
-                               st.st_uid = st.st_gid = self.getUid(parts[0])
-                       else:
-                               return -errno.ENOENT
-               elif depth == 2 and parts[-1] == '.k5login':
-                       st.st_mode = stat.S_IFREG | 0444
-                       st.st_nlink = 1
-                       st.st_size = len(self.getK5login(parts[0]))
-                       st.st_uid = st.st_gid = self.getUid(parts[0])
-               else:
-                       stats = list(os.lstat(self.mirrorPath(path)))
-                       stats[4:6] = [self.getUid(parts[0])] * 2
-                       return tuple(stats)
-               return st.toTuple()
-       
-       def readdir(self, path, offset):
-               print '*** readdir', path, offset
-               for (value, zero) in self.getdir(path):
-                       yield fuse.Direntry(value)
-       
-       def getdir(self, path):
-               print '*** getdir', path
-               if path == '/':
-                       contents = ['.', '..']+self.getMachines()
-               elif getDepth(path) == 1:
-                       contents = set(os.listdir(self.mirrorPath(path)) + ['.k5login', '.', '..'])
-               else:
-                       contents = os.listdir(self.mirrorPath(path)) + ['.', '..']
-               return [(i, 0) for i in contents]
-       
-       def read ( self, path, length, offset ):
-               print '*** read', path, length, offset
-               
-               parts = getParts(path)
-               
-               if getDepth(path) < 2:
-                       return -errno.ENOENT
-               elif parts[1:] == ['.k5login']:
-                       if parts[0] not in self.getMachines():
-                               return -errno.ENOENT
-                       else:
-                               return self.getK5login(parts[0])[offset:length + offset]
-               else:
-                       fname = self.mirrorPath(path)
-                       if not os.path.isfile(fname):
-                               return -errno.ENOENT
-                       else:
-                               f = open(fname)
-                               f.seek(offset)
-                               return f.read(length)
+               return princ.replace('.', '/') + '@' + realm
 
 if __name__ == '__main__':
-       sipb_xen_database.connect('postgres://sipb-xen@sipb-xen-dev.mit.edu/sipb_xen')
-       usage="""
-ConsoleFS [mount_path]
-"""
-       server = ConsoleFS()
-       server.flags = 0
-       server.main()
+       database.connect()
+       routefs.main(ConsoleFS)