~bzr-pqm/bzr/bzr.dev

# Copyright (C) 2006 by Canonical Ltd

#

# This program is free software; you can redistribute it and/or modify

# it under the terms of the GNU General Public License as published by

# the Free Software Foundation; either version 2 of the License, or

# (at your option) any later version.

#

# This program is distributed in the hope that it will be useful,

# but WITHOUT ANY WARRANTY; without even the implied warranty of

# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

# GNU General Public License for more details.

#

# You should have received a copy of the GNU General Public License

# along with this program; if not, write to the Free Software

# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

from bzrlib.bundle.serializer import read_bundle

import bzrlib.errors as errors

import bzrlib.urlutils

import bzrlib.transport

def read_bundle_from_url(url):

    """Read a bundle from a given URL.

    :return: A BundleReader, may raise NotABundle if the target 

            is not a proper bundle.

    """

    url, filename = bzrlib.urlutils.split(url, exclude_trailing_slash=False)

    if not filename:

        # A path to a directory was passed in

        # definitely not a bundle

        raise errors.NotABundle('A directory cannot be a bundle')

    # All of this must be in the try/except

    # Some transports cannot detect that we are trying to read a

    # directory until we actually issue read() on the handle.

    try:

        t = bzrlib.transport.get_transport(url)

        f = t.get(filename)

        return read_bundle(f)

    except (errors.TransportError, errors.PathError), e:

        raise errors.NotABundle(str(e))

    except (IOError,), e:

        # jam 20060707

        # Abstraction leakage, SFTPTransport.get('directory')

        # doesn't always fail at get() time. Sometimes it fails

        # during read. And that raises a generic IOError with

        # just the string 'Failure'

        # StubSFTPServer does fail during get() (because of prefetch) 

        # so it has an opportunity to translate the error.

        raise errors.NotABundle(str(e))