1# Copyright (C) 2005, 2006, 2007, 2009, 2010 Canonical Ltd
2#
3# This program is free software; you can redistribute it and/or modify
4# it under the terms of the GNU General Public License as published by
5# the Free Software Foundation; either version 2 of the License, or
6# (at your option) any later version.
7#
8# This program is distributed in the hope that it will be useful,
9# but WITHOUT ANY WARRANTY; without even the implied warranty of
10# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
11# GNU General Public License for more details.
12#
13# You should have received a copy of the GNU General Public License
14# along with this program; if not, write to the Free Software
15# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
16
17"""Serializer factory for reading and writing bundles.
18"""
19
20import base64
21from io import BytesIO
22import re
23
24from .... import (
25    errors,
26    registry,
27    )
28from ....diff import internal_diff
29from ....revision import NULL_REVISION
30# For backwards-compatibility
31from ....timestamp import unpack_highres_date, format_highres_date
32
33
34# New bundles should try to use this header format
35BUNDLE_HEADER = b'# Bazaar revision bundle v'
36BUNDLE_HEADER_RE = re.compile(
37    br'^# Bazaar revision bundle v(?P<version>\d+[\w.]*)(?P<lineending>\r?)\n$')
38CHANGESET_OLD_HEADER_RE = re.compile(
39    br'^# Bazaar-NG changeset v(?P<version>\d+[\w.]*)(?P<lineending>\r?)\n$')
40
41
42serializer_registry = registry.Registry()
43
44
45def _get_bundle_header(version):
46    return b''.join([BUNDLE_HEADER, version.encode('ascii'), b'\n'])
47
48
49def _get_filename(f):
50    return getattr(f, 'name', '<unknown>')
51
52
53def read_bundle(f):
54    """Read in a bundle from a filelike object.
55
56    :param f: A file-like object
57    :return: A list of Bundle objects
58    """
59    version = None
60    for line in f:
61        m = BUNDLE_HEADER_RE.match(line)
62        if m:
63            if m.group('lineending') != b'':
64                raise errors.UnsupportedEOLMarker()
65            version = m.group('version')
66            break
67        elif line.startswith(BUNDLE_HEADER):
68            raise errors.MalformedHeader(
69                'Extra characters after version number')
70        m = CHANGESET_OLD_HEADER_RE.match(line)
71        if m:
72            version = m.group('version')
73            raise errors.BundleNotSupported(version,
74                                            'old format bundles not supported')
75
76    if version is None:
77        raise errors.NotABundle('Did not find an opening header')
78
79    return get_serializer(version.decode('ascii')).read(f)
80
81
82def get_serializer(version):
83    try:
84        serializer = serializer_registry.get(version)
85    except KeyError:
86        raise errors.BundleNotSupported(version,
87                                        'unknown bundle format')
88
89    return serializer(version)
90
91
92def write(source, revision_ids, f, version=None, forced_bases={}):
93    """Serialize a list of bundles to a filelike object.
94
95    :param source: A source for revision information
96    :param revision_ids: The list of revision ids to serialize
97    :param f: The file to output to
98    :param version: [optional] target serialization version
99    """
100
101    with source.lock_read():
102        return get_serializer(version).write(source, revision_ids,
103                                             forced_bases, f)
104
105
106def write_bundle(repository, revision_id, base_revision_id, out, format=None):
107    """Write a bundle of revisions.
108
109    :param repository: Repository containing revisions to serialize.
110    :param revision_id: Head revision_id of the bundle.
111    :param base_revision_id: Revision assumed to be present in repositories
112         applying the bundle.
113    :param out: Output file.
114    :return: List of revision ids written
115    """
116    with repository.lock_read():
117        return get_serializer(format).write_bundle(repository, revision_id,
118                                                   base_revision_id, out)
119
120
121class BundleSerializer(object):
122    """The base class for Serializers.
123
124    Common functionality should be included here.
125    """
126
127    def __init__(self, version):
128        self.version = version
129
130    def read(self, f):
131        """Read the rest of the bundles from the supplied file.
132
133        :param f: The file to read from
134        :return: A list of bundle trees
135        """
136        raise NotImplementedError
137
138    def write_bundle(self, repository, target, base, fileobj):
139        """Write the bundle to the supplied file.
140
141        :param repository: The repository to retrieve revision data from
142        :param target: The revision to provide data for
143        :param base: The most recent of ancestor of the revision that does not
144            need to be included in the bundle
145        :param fileobj: The file to output to
146        :return: List of revision ids written
147        """
148        raise NotImplementedError
149
150
151def binary_diff(old_filename, old_lines, new_filename, new_lines, to_file):
152    temp = BytesIO()
153    internal_diff(old_filename, old_lines, new_filename, new_lines, temp,
154                  allow_binary=True)
155    temp.seek(0)
156    base64.encode(temp, to_file)
157    to_file.write(b'\n')
158
159
160serializer_registry.register_lazy(
161    '0.8', __name__ + '.v08', 'BundleSerializerV08')
162serializer_registry.register_lazy(
163    '0.9', __name__ + '.v09', 'BundleSerializerV09')
164serializer_registry.register_lazy('4', __name__ + '.v4',
165                                  'BundleSerializerV4')
166serializer_registry.default_key = '4'
167