~bzr-pqm/bzr/bzr.dev

# Copyright (C) 2005 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

"""Export functionality, which can take a Tree and create a different representation.

Such as non-controlled directories, tarfiles, zipfiles, etc.

"""

from bzrlib.trace import mutter

import os

import bzrlib.errors as errors

# Maps format name => export function

_exporters = {}

# Maps filename extensions => export format name

_exporter_extensions = {}

def register_exporter(format, extensions, func, override=False):

    """Register an exporter.

    :param format: This is the name of the format, such as 'tgz' or 'zip'

    :param extensions: Extensions which should be used in the case that a 

                       format was not explicitly specified.

    :type extensions: List

    :param func: The function. It will be called with (tree, dest, root)

    :param override: Whether to override an object which already exists.

                     Frequently plugins will want to provide functionality

                     until it shows up in mainline, so the default is False.

    """

    global _exporters, _exporter_extensions

    if (format not in _exporters) or override:

        _exporters[format] = func

    for ext in extensions:

        if (ext not in _exporter_extensions) or override:

            _exporter_extensions[ext] = format

def register_lazy_exporter(scheme, extensions, module, funcname):

    """Register lazy-loaded exporter function.

    When requesting a specific type of export, load the respective path.

    """

    def _loader(tree, dest, root):

        mod = __import__(module, globals(), locals(), [funcname])

        func = getattr(mod, funcname)

        return func(tree, dest, root)

    register_exporter(scheme, extensions, _loader)

def export(tree, dest, format=None, root=None):

    """Export the given Tree to the specific destination.

    :param tree: A Tree (such as RevisionTree) to export

    :param dest: The destination where the files,etc should be put

    :param format: The format (dir, zip, etc), if None, it will check the

                   extension on dest, looking for a match

    :param root: The root location inside the format.

                 It is common practise to have zipfiles and tarballs 

                 extract into a subdirectory, rather than into the

                 current working directory.

                 If root is None, the default root will be

                 selected as the destination without its

                 extension.

    """

    global _exporters, _exporter_extensions

    if format is None:

        for ext in _exporter_extensions:

            if dest.endswith(ext):

                format = _exporter_extensions[ext]

                break

    # Most of the exporters will just have to call

    # this function anyway, so why not do it for them

    if root is None:

        root = get_root_name(dest)

    if format not in _exporters:

        raise errors.NoSuchExportFormat(format)

    return _exporters[format](tree, dest, root)

def get_root_name(dest):

    """Get just the root name for an export.

    >>> get_root_name('../mytest.tar')

    'mytest'

    >>> get_root_name('mytar.tar')

    'mytar'

    >>> get_root_name('mytar.tar.bz2')

    'mytar'

    >>> get_root_name('tar.tar.tar.tgz')

    'tar.tar.tar'

    >>> get_root_name('bzr-0.0.5.tar.gz')

    'bzr-0.0.5'

    >>> get_root_name('bzr-0.0.5.zip')

    'bzr-0.0.5'

    >>> get_root_name('bzr-0.0.5')

    'bzr-0.0.5'

    >>> get_root_name('a/long/path/mytar.tgz')

    'mytar'

    >>> get_root_name('../parent/../dir/other.tbz2')

    'other'

    """

    global _exporter_extensions

    dest = os.path.basename(dest)

    for ext in _exporter_extensions:

        if dest.endswith(ext):

            return dest[:-len(ext)]

    return dest

register_lazy_exporter(None, [], 'bzrlib.export.dir_exporter', 'dir_exporter')

register_lazy_exporter('dir', [], 'bzrlib.export.dir_exporter', 'dir_exporter')

register_lazy_exporter('tar', ['.tar'], 'bzrlib.export.tar_exporter', 'tar_exporter')

register_lazy_exporter('tgz', ['.tar.gz', '.tgz'], 'bzrlib.export.tar_exporter', 'tgz_exporter')

register_lazy_exporter('tbz2', ['.tar.bz2', '.tbz2'], 'bzrlib.export.tar_exporter', 'tbz_exporter')

register_lazy_exporter('zip', ['.zip'], 'bzrlib.export.zip_exporter', 'zip_exporter')