/brz/remove-bazaar

# Copyright (C) 2008 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

"""Parameterised loading of revisions into a repository."""

from bzrlib import errors

class RevisionLoader(object):

    # NOTE: This is effectively bzrlib.repository._install_revision

    # refactored to be a class. When importing, we want more flexibility

    # in how previous revisions are cached, data is feed in, etc.

    def __init__(self, repo, inventories_provider=None):

        """An object responsible for loading revisions into a repository.

        NOTE: Repository locking is not managed by this class. Clients

        should take a write lock, call load() multiple times, then release

        the lock.

        :param repository: the target repository

        :param inventories_provider: a callable expecting a repository and

            a list of revision-ids, that returns:

              * the list of revision-ids present in the repository

              * the list of inventories for the revision-id's,

                including an empty inventory for the missing revisions

            If None, a default implementation is provided.

        """

        self.repo = repo

        if inventories_provider is not None:

            self.inventories_provider = inventories_provider

        else:

            self.inventories_provider = self._default_inventories_provider

    def load(self, rev, inv, signature, text_provider):

        """Load a revision into a repository.

        :param rev: the Revision

        :param inv: the inventory

        :param signature: signing information

        :param text_provider: a callable expecting a file_id parameter

            that returns the text for that file-id

        """

        present_parents, parent_invs = self.inventories_provider(

            rev.parent_ids)

        self._load_texts(rev.revision_id, inv.iter_entries(), parent_invs,

            text_provider)

        try:

            rev.inventory_sha1 = self.repo.add_inventory(rev.revision_id,

                inv, present_parents)

        except errors.RevisionAlreadyPresent:

            pass

        if signature is not None:

            self.repo.add_signature_text(rev.revision_id, signature)

        self.repo.add_revision(rev.revision_id, rev, inv)

    def _load_texts(self, revision_id, entries, parent_invs, text_provider):

        """Load texts to a repository for inventory entries.

        This method is provided for subclasses to use or override.

        :param revision_id: the revision identifier

        :param entries: iterator over the inventory entries

        :param parent_inv: the parent inventories

        :param text_provider: a callable expecting a file_id parameter

            that returns the text for that file-id

        """

        # Backwards compatibility hack: skip the root id.

        if not self.repo.supports_rich_root():

            path, root = entries.next()

            if root.revision != revision_id:

                raise errors.IncompatibleRevision(repr(self.repo))

        # Add the texts that are not already present

        tx = self.repo.get_transaction()

        for path, ie in entries:

            # This test is *really* slow: over 50% of import time

            #w = self.repo.weave_store.get_weave_or_empty(ie.file_id, tx)

            #if ie.revision in w:

            #    continue

            # Try another way, realising that this assumes that the

            # version is not already there. In the general case,

            # a shared repository might already have the revision but

            # we arguably don't need that check when importing from

            # a foreign system.

            if ie.revision != revision_id:

                continue

            text_parents = []

            for parent_inv in parent_invs:

                if ie.file_id not in parent_inv:

                    continue

                parent_id = parent_inv[ie.file_id].revision

                if parent_id in text_parents:

                    continue

                text_parents.append(parent_id)

            vfile = self.repo.weave_store.get_weave_or_empty(ie.file_id,  tx)

            lines = text_provider(ie.file_id)

            vfile.add_lines(revision_id, text_parents, lines)

    def _default_inventories_provider(self, revision_ids):

        """An inventories provider that queries the repository."""

        present = []

        inventories = []

        for revision_id in revision_ids:

            if self.repo.has_revision(revision_id):

                present.append(revision_id)

                rev_tree = self.repo.revision_tree(revision_id)

            else:

                rev_tree = self.repo.revision_tree(None)

            inventories.append(rev_tree.inventory)

        return present, inventories