~bzr-pqm/bzr/bzr.dev

# Copyright (C) 2007 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 email import Message

from StringIO import StringIO

from bzrlib import (

    branch as _mod_branch,

    diff,

    errors,

    gpg,

    revision as _mod_revision,

    rio,

    testament,

    timestamp,

    )

from bzrlib.bundle import (

    serializer as bundle_serializer,

    )

class MergeDirective(object):

    """A request to perform a merge into a branch.

    Designed to be serialized and mailed.  It provides all the information

    needed to perform a merge automatically, by providing at minimum a revision

    bundle or the location of a branch.

    The serialization format is robust against certain common forms of

    deterioration caused by mailing.

    The format is also designed to be patch-compatible.  If the directive

    includes a diff or revision bundle, it should be possible to apply it

    directly using the standard patch program.

    """

    _format_string = 'Bazaar merge directive format 1'

    def __init__(self, revision_id, testament_sha1, time, timezone,

                 target_branch, patch=None, patch_type=None,

                 source_branch=None, message=None):

        """Constructor.

        :param revision_id: The revision to merge

        :param testament_sha1: The sha1 of the testament of the revision to

            merge.

        :param time: The current POSIX timestamp time

        :param timezone: The timezone offset

        :param target_branch: The branch to apply the merge to

        :param patch: The text of a diff or bundle

        :param patch_type: None, "diff" or "bundle", depending on the contents

            of patch

        :param source_branch: A public location to merge the revision from

        :param message: The message to use when committing this merge

        """

        assert patch_type in (None, 'diff', 'bundle')

        if patch_type != 'bundle' and source_branch is None:

            raise errors.NoMergeSource()

        if patch_type is not None and patch is None:

            raise errors.PatchMissing(patch_type)

        self.revision_id = revision_id

        self.testament_sha1 = testament_sha1

        self.time = time

        self.timezone = timezone

        self.target_branch = target_branch

        self.patch = patch

        self.patch_type = patch_type

        self.source_branch = source_branch

        self.message = message

    @classmethod

    def from_lines(klass, lines):

        """Deserialize a MergeRequest from an iterable of lines

        :param lines: An iterable of lines

        :return: a MergeRequest

        """

        line_iter = iter(lines)

        for line in line_iter:

            if line.startswith('# ' + klass._format_string):

                break

        else:

            if len(lines) > 0:

                raise errors.NotAMergeDirective(lines[0])

            else:

                raise errors.NotAMergeDirective('')

        stanza = rio.read_patch_stanza(line_iter)

        patch_lines = list(line_iter)

        if len(patch_lines) == 0:

            patch = None

            patch_type = None

        else:

            patch = ''.join(patch_lines)

            try:

                bundle_serializer.read_bundle(StringIO(patch))

            except (errors.NotABundle, errors.BundleNotSupported,

                    errors.BadBundle):

                patch_type = 'diff'

            else:

                patch_type = 'bundle'

        time, timezone = timestamp.parse_patch_date(stanza.get('timestamp'))

        kwargs = {}

        for key in ('revision_id', 'testament_sha1', 'target_branch',

                    'source_branch', 'message'):

            try:

                kwargs[key] = stanza.get(key)

            except KeyError:

                pass

        kwargs['revision_id'] = kwargs['revision_id'].encode('utf-8')

        return MergeDirective(time=time, timezone=timezone,

                              patch_type=patch_type, patch=patch, **kwargs)

    def to_lines(self):

        """Serialize as a list of lines

        :return: a list of lines

        """

        time_str = timestamp.format_patch_date(self.time, self.timezone)

        stanza = rio.Stanza(revision_id=self.revision_id, timestamp=time_str,

                            target_branch=self.target_branch,

                            testament_sha1=self.testament_sha1)

        for key in ('source_branch', 'message'):

            if self.__dict__[key] is not None:

                stanza.add(key, self.__dict__[key])

        lines = ['# ' + self._format_string + '\n']

        lines.extend(rio.to_patch_lines(stanza))

        lines.append('# \n')

        if self.patch is not None:

            lines.extend(self.patch.splitlines(True))

        return lines

    def to_signed(self, branch):

        """Serialize as a signed string.

        :param branch: The source branch, to get the signing strategy

        :return: a string

        """

        my_gpg = gpg.GPGStrategy(branch.get_config())

        return my_gpg.sign(''.join(self.to_lines()))

    def to_email(self, mail_to, branch, sign=False):

        """Serialize as an email message.

        :param mail_to: The address to mail the message to

        :param branch: The source branch, to get the signing strategy and

            source email address

        :param sign: If True, gpg-sign the email

        :return: an email message

        """

        mail_from = branch.get_config().username()

        message = Message.Message()

        message['To'] = mail_to

        message['From'] = mail_from

        if self.message is not None:

            message['Subject'] = self.message

        else:

            revision = branch.repository.get_revision(self.revision_id)

            message['Subject'] = revision.message

        if sign:

            body = self.to_signed(branch)

        else:

            body = ''.join(self.to_lines())

        message.set_payload(body)

        return message

    @classmethod

    def from_objects(klass, repository, revision_id, time, timezone,

                 target_branch, patch_type='bundle',

                 local_target_branch=None, public_branch=None, message=None):

        """Generate a merge directive from various objects

        :param repository: The repository containing the revision

        :param revision_id: The revision to merge

        :param time: The POSIX timestamp of the date the request was issued.

        :param timezone: The timezone of the request

        :param target_branch: The url of the branch to merge into

        :param patch_type: 'bundle', 'diff' or None, depending on the type of

            patch desired.

        :param local_target_branch: a local copy of the target branch

        :param public_branch: location of a public branch containing the target

            revision.

        :param message: Message to use when committing the merge

        :return: The merge directive

        The public branch is always used if supplied.  If the patch_type is

        not 'bundle', the public branch must be supplied, and will be verified.

        If the message is not supplied, the message from revision_id will be

        used for the commit.

        """

        t_revision_id = revision_id

        if revision_id == 'null:':

            t_revision_id = None

        t = testament.StrictTestament3.from_revision(repository, t_revision_id)

        submit_branch = _mod_branch.Branch.open(target_branch)

        if submit_branch.get_public_branch() is not None:

            target_branch = submit_branch.get_public_branch()

        if patch_type is None:

            patch = None

        else:

            submit_revision_id = submit_branch.last_revision()

            submit_revision_id = _mod_revision.ensure_null(submit_revision_id)

            repository.fetch(submit_branch.repository, submit_revision_id)

            graph = repository.get_graph()

            ancestor_id = graph.find_unique_lca(revision_id,

                                                submit_revision_id)

            type_handler = {'bundle': klass._generate_bundle,

                            'diff': klass._generate_diff,

                            None: lambda x, y, z: None }

            patch = type_handler[patch_type](repository, revision_id,

                                             ancestor_id)

            if patch_type == 'bundle':

                s = StringIO()

                bundle_serializer.write_bundle(repository, revision_id,

                                               ancestor_id, s)

                patch = s.getvalue()

            elif patch_type == 'diff':

                patch = klass._generate_diff(repository, revision_id,

                                             ancestor_id)

            if public_branch is not None and patch_type != 'bundle':

                public_branch_obj = _mod_branch.Branch.open(public_branch)

                if not public_branch_obj.repository.has_revision(revision_id):

                    raise errors.PublicBranchOutOfDate(public_branch,

                                                       revision_id)

        return MergeDirective(revision_id, t.as_sha1(), time, timezone,

                              target_branch, patch, patch_type, public_branch,

                              message)

    @staticmethod

    def _generate_diff(repository, revision_id, ancestor_id):

        tree_1 = repository.revision_tree(ancestor_id)

        tree_2 = repository.revision_tree(revision_id)

        s = StringIO()

        diff.show_diff_trees(tree_1, tree_2, s, old_label='', new_label='')

        return s.getvalue()

    @staticmethod

    def _generate_bundle(repository, revision_id, ancestor_id):

        s = StringIO()

        bundle_serializer.write_bundle(repository, revision_id,

                                       ancestor_id, s)

        return s.getvalue()

    def install_revisions(self, target_repo):

        """Install revisions and return the target revision"""

        if not target_repo.has_revision(self.revision_id):

            if self.patch_type == 'bundle':

                info = bundle_serializer.read_bundle(StringIO(self.patch))

                # We don't use the bundle's target revision, because

                # MergeDirective.revision_id is authoritative.

                info.install_revisions(target_repo)

            else:

                source_branch = _mod_branch.Branch.open(self.source_branch)

                target_repo.fetch(source_branch.repository, self.revision_id)

        return self.revision_id