bin/pvlbackup-rsync-wrapper
changeset 41 921b45c4678b
parent 34 8c23dc925ed7
child 42 43e27a3e9efe
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/bin/pvlbackup-rsync-wrapper	Sun Apr 22 12:13:26 2012 +0300
@@ -0,0 +1,169 @@
+#!/usr/bin/python
+
+"""
+    SSH authorized_keys command="..." wrapper for rsync.
+
+    Testing goes something like:
+        sudo sh -c "PYTHONPATH=. rsync -e './scripts/pvlbackup-rsync-wrapper --debug -C --' -ax testing:lvm:asdf:test test/tmp"
+"""
+
+from pvl.backup import __version__
+from pvl.backup.rsync import RSyncCommandFormatError
+from pvl.backup.invoke import InvokeError
+from pvl.backup import rsync
+
+import optparse
+import shlex
+import os
+import logging
+
+log = logging.getLogger()
+
+# command-line options
+options = None
+
+def parse_options (argv) :
+    """
+        Parse command-line arguments.
+    """
+
+#    import sys; sys.stderr.write("%s\n" % (argv, ))
+
+    parser = optparse.OptionParser(
+            prog        = argv[0],
+
+            # module docstring
+            description = __doc__,
+            version     = __version__,
+    )
+
+    # logging
+    general = optparse.OptionGroup(parser, "General Options")
+
+    general.add_option('-q', '--quiet',      dest='loglevel', action='store_const', const=logging.WARNING, help="Less output")
+    general.add_option('-v', '--verbose',    dest='loglevel', action='store_const', const=logging.INFO,  help="More output")
+    general.add_option('-D', '--debug',      dest='loglevel', action='store_const', const=logging.DEBUG, help="Even more output")
+    general.add_option('--debug-for',        action='append', metavar='MODULE', help="Enable logging for the given logger/module name")
+
+    parser.add_option_group(general)
+
+    #
+    parser.add_option('-c', '--command',    metavar='CMD', default=os.environ.get('SSH_ORIGINAL_COMMAND'),
+            help="rsync command to execute")
+
+    parser.add_option('-C', '--given-command', action='store_true', default=False,
+            help="use given command in `rsync -e %prog` format")
+
+    parser.add_option('-R', '--readonly',   action='store_true', default=False,
+            help="restrict to read/source mode")
+
+    parser.add_option('-P', '--restrict-path', metavar='PATH', default=False,
+            help="restrict to given path prefix")
+
+    # defaults
+    parser.set_defaults(
+        debug_for   = [],
+        loglevel    = logging.INFO,
+    )
+
+    # parse
+    options, args = parser.parse_args(argv[1:])
+
+    # configure
+    logging.basicConfig(
+        format  = '%(levelname)6s %(name)s : %(funcName)s : %(message)s',
+        level   = options.loglevel,
+    )
+
+    # enable debugging for specific targets
+    for target in options.debug_for :
+        logging.getLogger(target).setLevel(logging.DEBUG)
+
+    return options, args
+
+def rsync_wrapper (command, restrict='lvm:') :
+    """
+        Wrap given rsync command.
+
+        Parses the command, the source path, and then executes rsync within the source path (which may be a special
+        pseudo-path with additional handling).
+    """
+
+    try :
+        # parse the rsync command sent by the client
+        rsync_cmd, rsync_options, source_path, dest_path = rsync.parse_command(command, 
+                restrict_readonly   = options.readonly,
+            )
+
+    except RSyncCommandFormatError, e:
+        log.error("invalid rsync command: %r: %s", command, e)
+        return 2
+
+    # XXX: the real path is always given second..
+    path = dest_path
+
+    try :
+        # parse the source path as given by the client, may be a real path or pseudo-path
+        source = rsync.parse_source(path,
+                restrict_path       = options.restrict_path,
+            )
+
+    except RSyncCommandFormatError, e:
+        log.error("invalid rsync source: %r: %s", path, e)
+        return 2
+
+    try :
+        # run rsync within the source (may perform additional stuff like snapshotting...)
+        source.execute(rsync_options)
+
+    except InvokeError, e:
+        log.error("%s failed: %d", e.cmd, e.exit)
+        return e.exit
+
+    # ok
+    return 0
+
+def main (argv) :
+    global options
+
+    # global options + args
+    options, args = parse_options(argv)
+
+    # command required
+    if options.given_command :
+        # from args (as given by `rsync -e pvlbackup-rsync-wrapper`) -> 'pvlbackup-rsync-wrapper <host> (<command> ...)'
+        host = args.pop(0)
+        command_parts = args
+
+        log.debug("using command from args: %r", command_parts)
+
+    # args
+    elif args :
+        log.error("No arguments are handled")
+        return 2
+
+    elif options.command:
+        # as given
+        command_parts = shlex.split(options.command)
+
+    else :
+        log.error("SSH_ORIGINAL_COMMAND not given")
+        return 2
+
+
+    # run
+    try :
+        return rsync_wrapper(command_parts)
+
+    except Exception, e:
+        log.error("Internal error:", exc_info=e)
+        return 3
+
+    # ok
+    return 0
+
+if __name__ == '__main__' :
+    import sys
+
+    sys.exit(main(sys.argv))
+