/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

"""Import processor that supports all Bazaar repository formats."""

import time

from bzrlib import (

    delta,

    errors,

    generate_ids,

    inventory,

    lru_cache,

    osutils,

    revision,

    revisiontree,

    )

from bzrlib.trace import (

    note,

    warning,

    )

from bzrlib.plugins.fastimport import (

    processor,

    revisionloader,

    )

def _single_plural(n, single, plural):

    """Return a single or plural form of a noun based on number."""

    if n == 1:

        return single

    else:

        return plural

class GenericProcessor(processor.ImportProcessor):

    """An import processor that handles basic imports.

    Current features supported:

    * timestamped progress reporting

    * blobs are cached in memory until used

    * TODO: commit handling

    * LATER: branch support

    * checkpoints and tags are ignored

    * some basic statistics are dumped on completion.

    """

    def pre_process(self):

        self.cache_mgr = GenericCacheManager()

        self.active_branch = self.branch

        self.init_stats()

        # mapping of tag name to revision_id

        self.tags = {}

    def post_process(self):

        self.dump_stats()

        # Update the branches, assuming the last revision is the head

        note("Updating branch information ...")

        # TODO - loop over the branches created/modified

        last_rev_id = self.cache_mgr.last_revision_ids[self.branch]

        revno = len(list(self.repo.iter_reverse_revision_history(last_rev_id)))

        self.branch.set_last_revision_info(revno, last_rev_id)

        if self.tags:

            self.branch.tags._set_tag_dict(self.tags)

        # Update the working tree, if any

        if self.working_tree:

            self.working_tree.update(delta._ChangeReporter())

    def init_stats(self):

        self._revision_count = 0

        self._branch_count = 1

        self._tag_count = 0

    def dump_stats(self):

        rc = self._revision_count

        bc = self._branch_count

        tc = self._tag_count

        note("Imported %d %s into %d %s with %d %s.",

            rc, _single_plural(rc, "revision", "revisions"),

            bc, _single_plural(bc, "branch", "branches"),

            tc, _single_plural(tc, "tag", "tags"))

    def blob_handler(self, cmd):

        """Process a BlobCommand."""

        if cmd.mark is not None:

            dataref = ":%s" % (cmd.mark,)

        else:

            dataref = osutils.sha_strings(cmd.data)

        self.cache_mgr.blobs[dataref] = cmd.data

    def checkpoint_handler(self, cmd):

        """Process a CheckpointCommand."""

        warning("ignoring checkpoint")

    def commit_handler(self, cmd):

        """Process a CommitCommand."""

        handler = GenericCommitHandler(cmd, self.repo, self.cache_mgr,

            self.active_branch)

        # For now, put a write group around every commit. In the future,

        # we might only start/commit one every N to sppeed things up

        self.repo.start_write_group()

        try:

            handler.process()

            self.cache_mgr.revision_ids[cmd.ref] = handler.revision_id

            self.cache_mgr.last_revision_ids[self.active_branch] = \

                handler.revision_id

            self._revision_count += 1

        except:

            self.repo.abort_write_group()

            raise

        else:

            self.repo.commit_write_group()

    def progress_handler(self, cmd):

        """Process a ProgressCommand."""

        # We could use a progress bar here but timestamped messages

        # is more useful for determining when things might complete

        note("%s progress %s" % (self._time_of_day(), cmd.message))

    def _time_of_day(self):

        """Time of day as a string."""

        # Note: this is a separate method so tests can patch in a fixed value

        return time.localtime().strftime("%H:%M:%s")

    def reset_handler(self, cmd):

        """Process a ResetCommand."""

        if cmd.ref.startswith('refs/tags/'):

            self._set_tag(cmd.ref[len('refs/tags/'):], cmd.from_)

        else:

            warning("multiple branches are not supported yet"

                " - ignoring branch '%s'", cmd.ref)

    def tag_handler(self, cmd):

        """Process a TagCommand."""

        self._set_tag(cmd.id, cmd.from_)

    def _set_tag(self, name, from_):

        """Define a tag given a name an import 'from' reference."""

        bzr_tag_name = name.decode('utf-8', 'replace')

        bzr_rev_id = self.cache_mgr.revision_ids[from_]

        self.tags[bzr_tag_name] = bzr_rev_id

        self._tag_count += 1

class GenericCacheManager(object):

    """A manager of caches for the GenericProcessor."""

    def __init__(self, inventory_cache_size=100):

        # dataref -> data. datref is either :mark or the sha-1.

        # Once a blob is used, it should be deleted from here.

        self.blobs = {}

        # revision-id -> Inventory cache

        # these are large and we probably don't need too many as

        # most parents are recent in history

        self.inventories = lru_cache.LRUCache(inventory_cache_size)

        # directory-path -> inventory-entry lookup table

        # we need to keep all of these but they are small

        self.directory_entries = {}

        # import-ref -> revision-id lookup table

        # we need to keep all of these but they are small

        self.revision_ids = {}

        # branch -> last revision-id lookup table

        self.last_revision_ids = {}

class GenericCommitHandler(processor.CommitHandler):

    def __init__(self, command, repo, cache_mgr, active_branch):

        processor.CommitHandler.__init__(self, command)

        self.repo = repo

        self.cache_mgr = cache_mgr

        self.active_branch = active_branch

        # smart loader that uses these caches

        self.loader = revisionloader.RevisionLoader(repo,

            lambda revision_ids: self._get_inventories(revision_ids))

    def pre_process_files(self):

        """Prepare for committing."""

        self.revision_id = self.gen_revision_id()

        self.inv_delta = []

        # cache of texts for this commit, indexed by file-id

        self.lines_for_commit = {}

    def post_process_files(self):

        """Save the revision."""

        if self.command.parents:

            parents = [self.cache_mgr.revision_ids[ref]

                for ref in self.command.parents]

        else:

            # if no parents are given, the last revision on

            # the current branch is assumed according to the spec

            last_rev = self.cache_mgr.last_revision_ids.get(

                    self.active_branch)

            if last_rev:

                parents = [last_rev]

            else:

                parents = []

        # Derive the inventory from the previous one

        if len(parents) == 0:

            new_inventory = self.gen_initial_inventory()

        else:

            # use the bzr_revision_id to lookup the inv cache

            new_inventory = self.get_inventory(parents[0]).copy()

        if not self.repo.supports_rich_root():

            # In this repository, root entries have no knit or weave. When

            # serializing out to disk and back in, root.revision is always

            # the new revision_id.

            new_inventory.root.revision = self.revision_id

        new_inventory.apply_delta(self.inv_delta)

        self.cache_mgr.inventories[self.command.ref] = new_inventory

        # debug trace ...

        print "applied inventory delta ..."

        for entry in self.inv_delta:

            print "  %r" % (entry,)

        print "creating inventory ..."

        for entry in new_inventory:

            print "  %r" % (entry,)

        # Load the revision into the repository

        # TODO: Escape the commit message

        committer = self.command.committer

        who = "%s <%s>" % (committer[0],committer[1])

        rev = revision.Revision(self.revision_id)

        rev = revision.Revision(

           timestamp=committer[2],

           timezone=committer[3],

           committer=who,

           message=self.escape_commit_message(self.command.message),

           revision_id=self.revision_id)

        rev.parent_ids = parents

        self.loader.load(rev, new_inventory, None,

            lambda file_id: self._get_lines(file_id))

        print "loaded revision %r" % (rev,)

    def escape_commit_message(self, msg):

        # It's crap that we need to do this at this level (but we do)

        # TODO

        return msg

    def modify_handler(self, filecmd):

        if filecmd.dataref is not None:

            data = self.cache_mgr.blobs[filecmd.dataref]

            # Conserve memory, assuming blobs aren't referenced twice

            del self.cache_mgr.blobs[filecmd.dataref]

        else:

            data = filecmd.data

        self._modify_inventory(filecmd.path, filecmd.kind,

            filecmd.is_executable, data)

    def delete_handler(self, filecmd):

        path = filecmd.path

        self.inv_delta.append((path, None, self.bzr_file_id(path), None))

    def copy_handler(self, filecmd):

        raise NotImplementedError(self.copy_handler)

    def rename_handler(self, filecmd):

        # TODO: add a suitable entry to the inventory delta

        raise NotImplementedError(self.rename_handler)

    def deleteall_handler(self, filecmd):

        raise NotImplementedError(self.deleteall_handler)

    def bzr_file_id(self, path):

        """Generate a Bazaar file identifier for a path."""

        # TODO: Search the current inventory instead of generating every time

        return generate_ids.gen_file_id(path)

    def gen_initial_inventory(self):

        """Generate an inventory for a parentless revision."""

        inv = inventory.Inventory(revision_id=self.revision_id)

        return inv

    def gen_revision_id(self):

        """Generate a revision id.

        Subclasses may override this to produce deterministic ids say.

        """

        committer = self.command.committer

        who = "%s <%s>" % (committer[0],committer[1])

        timestamp = committer[2]

        return generate_ids.gen_revision_id(who, timestamp)

    def get_inventory(self, revision_id):

        """Get the inventory for a revision id."""

        try:

            inv = self.cache_mgr.inventories[revision_id]

        except KeyError:

            # TODO: count misses and/or inform the user about the miss?

            # Not cached so reconstruct from repository

            inv = self.repo.revision_tree(revision_id).inventory

            self.cache_mgr.inventories[revision_id] = inv

        return inv

    def _get_inventories(self, revision_ids):

        """Get the inventories for revision-ids.

        This is a callback used by the RepositoryLoader to

        speed up inventory reconstruction."""

        present = []

        inventories = []

        # If an inventory is in the cache, we assume it was

        # successfully loaded into the repsoitory

        for revision_id in revision_ids:

            try:

                inv = self.cache_mgr.inventories[revision_id]

                present.append(revision_id)

            except KeyError:

                # TODO: count misses and/or inform the user about the miss?

                # Not cached so reconstruct from repository

                if self.repo.has_revision(revision_id):

                    rev_tree = self.repo.revision_tree(revision_id)

                    present.append(revision_id)

                else:

                    rev_tree = self.repo.revision_tree(None)

                inv = rev_tree.inventory

                self.cache_mgr.inventories[revision_id] = inv

            inventories.append(inv)

        return present, inventories

    def _get_lines(self, file_id):

        """Get the lines for a file-id."""

        return self.lines_for_commit[file_id]

    def _modify_inventory(self, path, kind, is_executable, data):

        """Add to or change an item in the inventory."""

        # Create the new InventoryEntry

        basename, parent_ie = self._ensure_directory(path)

        file_id = self.bzr_file_id(path)

        ie = inventory.make_entry(kind, basename, parent_ie, file_id)

        ie.revision = self.revision_id

        if isinstance(ie, inventory.InventoryFile):

            ie.executable = is_executable

            lines = osutils.split_lines(data)

            ie.text_sha1 = osutils.sha_strings(lines)

            ie.text_size = sum(map(len, lines))

            self.lines_for_commit[file_id] = lines

        elif isinstance(ie, inventory.InventoryLnk):

            ie.symlink_target = data

        else:

            raise errors.BzrError("Cannot import items of kind '%s' yet" %

                (kind,))

        # Record this new inventory entry. As the import stream doesn't

        # repeat all files every time, we build an inventory delta.

        # HACK: We also assume that inventory.apply_delta handles the

        # 'add' case cleanly when asked to change a non-existent entry.

        # This saves time vs explicitly detecting add vs change.

        old_path = path

        self.inv_delta.append((old_path, path, file_id, ie))

    def _ensure_directory(self, path):

        """Ensure that the containing directory exists for 'path'"""

        dirname, basename = osutils.split(path)

        if dirname == '':

            # the root node doesn't get updated

            return basename, inventory.ROOT_ID

        try:

            ie = self.cache_mgr.directory_entries[dirname]

        except KeyError:

            # We will create this entry, since it doesn't exist

            pass

        else:

            return basename, ie

        # No directory existed, we will just create one, first, make sure

        # the parent exists

        dir_basename, parent_ie = self._ensure_directory(dirname)

        dir_file_id = self.bzr_file_id(dirname)

        ie = inventory.entry_factory['directory'](dir_file_id,

                                                  dir_basename,

                                                  parent_ie.file_id)

        ie.revision = self.revision_id

        self.cache_mgr.directory_entries[dirname] = ie

        self.inv_delta.append((None, path, dir_file_id, ie))

        return basename, ie