/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, knit, lru_cache, osutils

from bzrlib import revision as _mod_revision

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):

        """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

        """

        self.repo = repo

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

        inventories_provider=None):

        """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

        :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.

        """

        if inventories_provider is None:

            inventories_provider = self._default_inventories_provider

        present_parents, parent_invs = inventories_provider(rev.parent_ids)

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

            text_provider)

        try:

            rev.inventory_sha1 = self._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 _add_inventory(self, revision_id, inv, parents):

        """Add the inventory inv to the repository as revision_id.

        :param parents: The revision ids of the parents that revision_id

                        is known to have and are in the repository already.

        :returns: The validator(which is a sha1 digest, though what is sha'd is

            repository format specific) of the serialized inventory.

        """

        return self.repo.add_inventory(revision_id, inv, parents)

    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

class ImportRevisionLoader(RevisionLoader):

    """A RevisionLoader optimised for importing.

    This implementation caches serialised inventory texts.

    """

    def __init__(self, repo, parent_texts_to_cache=1, random_ids=True):

        """See RevisionLoader.__init__.

        :param repository: the target repository

        :param parent_text_to_cache: the number of parent texts to cache

        """

        RevisionLoader.__init__(self, repo)

        self.inv_parent_texts = lru_cache.LRUCache(parent_texts_to_cache)

        self.random_ids = random_ids

    def _add_inventory(self, revision_id, inv, parents):

        """See RevisionLoader._add_inventory."""

        # Code taken from bzrlib.repository.add_inventory

        assert self.repo.is_in_write_group()

        _mod_revision.check_not_reserved_id(revision_id)

        assert inv.revision_id is None or inv.revision_id == revision_id, \

            "Mismatch between inventory revision" \

            " id and insertion revid (%r, %r)" % (inv.revision_id, revision_id)

        assert inv.root is not None

        inv_lines = self.repo._serialise_inventory_to_lines(inv)

        inv_vf = self.repo.get_inventory_weave()

        sha1, num_bytes, parent_text = self._inventory_add_lines(inv_vf,

            revision_id, parents, inv_lines, self.inv_parent_texts)

        self.inv_parent_texts[revision_id] = parent_text

        return sha1

    def _inventory_add_lines(self, inv_vf, version_id, parents, lines,

            parent_texts):

        """See Repository._inventory_add_lines()."""

        final_parents = []

        for parent in parents:

            if parent in inv_vf:

                final_parents.append(parent)

        return inv_vf.add_lines(version_id, final_parents, lines, parent_texts,

            random_id=self.random_ids, check_content=False)

class ExperimentalRevisionLoader(ImportRevisionLoader):

    """A RevisionLoader over optimised for importing.

    WARNING: This implementation uses undoumented bzrlib internals.

    It may not work in the future. In fact, it may not work now as

    it is an incubator for experimental code.

    """

    def __init__(self, repo, parent_texts_to_cache=1, fulltext_every=200):

        """See ImportRevisionLoader.__init__.

        :para fulltext_every: how often to store an inventory fulltext

        """

        ImportRevisionLoader.__init__(self, repo, parent_texts_to_cache)

        self.revision_count = 0

        self.fulltext_every = fulltext_every

    def _inventory_add_lines(self, inv_vf, version_id, parents, lines,

            parent_texts):

        """See Repository._inventory_add_lines()."""

        # setup parameters used in original code but not this API

        self.revision_count += 1

        if self.revision_count % self.fulltext_every == 0:

            delta = False

        else:

            delta = inv_vf.delta

        left_matching_blocks = None

        random_id = self.random_ids

        check_content = False

        # bzrlib.knit.add_lines() but error checking optimised

        inv_vf._check_add(version_id, lines, random_id, check_content)

        ####################################################################

        # bzrlib.knit._add() but skip checking if fulltext better than delta

        ####################################################################

        line_bytes = ''.join(lines)

        digest = osutils.sha_string(line_bytes)

        present_parents = []

        for parent in parents:

            if inv_vf.has_version(parent):

                present_parents.append(parent)

        if parent_texts is None:

            parent_texts = {}

        # can only compress against the left most present parent.

        if (delta and

            (len(present_parents) == 0 or

             present_parents[0] != parents[0])):

            delta = False

        text_length = len(line_bytes)

        options = []

        if lines:

            if lines[-1][-1] != '\n':

                # copy the contents of lines.

                lines = lines[:]

                options.append('no-eol')

                lines[-1] = lines[-1] + '\n'

                line_bytes += '\n'

        #if delta:

        #    # To speed the extract of texts the delta chain is limited

        #    # to a fixed number of deltas.  This should minimize both

        #    # I/O and the time spend applying deltas.

        #    delta = inv_vf._check_should_delta(present_parents)

        assert isinstance(version_id, str)

        content = inv_vf.factory.make(lines, version_id)

        if delta or (inv_vf.factory.annotated and len(present_parents) > 0):

            # Merge annotations from parent texts if needed.

            delta_hunks = inv_vf._merge_annotations(content, present_parents,

                parent_texts, delta, inv_vf.factory.annotated,

                left_matching_blocks)

        if delta:

            options.append('line-delta')

            store_lines = inv_vf.factory.lower_line_delta(delta_hunks)

            size, bytes = inv_vf._data._record_to_data(version_id, digest,

                store_lines)

        else:

            options.append('fulltext')

            # isinstance is slower and we have no hierarchy.

            if inv_vf.factory.__class__ == knit.KnitPlainFactory:

                # Use the already joined bytes saving iteration time in

                # _record_to_data.

                size, bytes = inv_vf._data._record_to_data(version_id, digest,

                    lines, [line_bytes])

            else:

                # get mixed annotation + content and feed it into the

                # serialiser.

                store_lines = inv_vf.factory.lower_fulltext(content)

                size, bytes = inv_vf._data._record_to_data(version_id, digest,

                    store_lines)

        access_memo = inv_vf._data.add_raw_records([size], bytes)[0]

        inv_vf._index.add_versions(

            ((version_id, options, access_memo, parents),),

            random_id=random_id)

        return digest, text_length, content