~jelmer/bzr-git/705807-dpush

# Copyright (C) 2007 Canonical Ltd

# Copyright (C) 2008-2010 Jelmer Vernooij <jelmer@samba.org>

# Copyright (C) 2008 John Carr

#

# 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

"""Converters, etc for going between Bazaar and Git ids."""

import base64

import stat

from bzrlib import (

    bencode,

    errors,

    foreign,

    trace,

    )

from bzrlib.inventory import (

    ROOT_ID,

    )

from bzrlib.foreign import (

    ForeignVcs,

    VcsMappingRegistry,

    ForeignRevision,

    )

from bzrlib.revision import (

    NULL_REVISION,

    )

from bzrlib.plugins.git.hg import (

    format_hg_metadata,

    extract_hg_metadata,

    )

from bzrlib.plugins.git.roundtrip import (

    extract_bzr_metadata,

    inject_bzr_metadata,

    BzrGitRevisionMetadata,

    deserialize_fileid_map,

    serialize_fileid_map,

    )

DEFAULT_FILE_MODE = stat.S_IFREG | 0644

def escape_file_id(file_id):

    return file_id.replace('_', '__').replace(' ', '_s')

def unescape_file_id(file_id):

    ret = []

    i = 0

    while i < len(file_id):

        if file_id[i] != '_':

            ret.append(file_id[i])

        else:

            if file_id[i+1] == '_':

                ret.append("_")

            elif file_id[i+1] == 's':

                ret.append(" ")

            else:

                raise AssertionError("unknown escape character %s" %

                    file_id[i+1])

            i += 1

        i += 1

    return "".join(ret)

def fix_person_identifier(text):

    if "<" in text and ">" in text:

        return text

    return "%s <%s>" % (text, text)

def warn_escaped(commit, num_escaped):

    trace.warning("Escaped %d XML-invalid characters in %s. Will be unable "

                  "to regenerate the SHA map.", num_escaped, commit)

def warn_unusual_mode(commit, path, mode):

    trace.mutter("Unusual file mode %o for %s in %s. Storing as revision "

                 "property. ", mode, path, commit)

class BzrGitMapping(foreign.VcsMapping):

    """Class that maps between Git and Bazaar semantics."""

    experimental = False

    BZR_FILE_IDS_FILE = None

    BZR_DUMMY_FILE = None

    def __init__(self):

        super(BzrGitMapping, self).__init__(foreign_git)

    def __eq__(self, other):

        return (type(self) == type(other) and

                self.revid_prefix == other.revid_prefix)

    @classmethod

    def revision_id_foreign_to_bzr(cls, git_rev_id):

        """Convert a git revision id handle to a Bazaar revision id."""

        from dulwich.protocol import ZERO_SHA

        if git_rev_id == ZERO_SHA:

            return NULL_REVISION

        return "%s:%s" % (cls.revid_prefix, git_rev_id)

    @classmethod

    def revision_id_bzr_to_foreign(cls, bzr_rev_id):

        """Convert a Bazaar revision id to a git revision id handle."""

        if not bzr_rev_id.startswith("%s:" % cls.revid_prefix):

            raise errors.InvalidRevisionId(bzr_rev_id, cls)

        return bzr_rev_id[len(cls.revid_prefix)+1:], cls()

    def generate_file_id(self, path):

        # Git paths are just bytestrings

        # We must just hope they are valid UTF-8..

        if path == "":

            return ROOT_ID

        if type(path) is unicode:

            path = path.encode("utf-8")

        return escape_file_id(path)

    def is_control_file(self, path):

        return path in (self.BZR_FILE_IDS_FILE, self.BZR_DUMMY_FILE)

    def parse_file_id(self, file_id):

        if file_id == ROOT_ID:

            return ""

        return unescape_file_id(file_id)

    def revid_as_refname(self, revid):

        import urllib

        return "refs/bzr/%s" % urllib.quote(revid)

    def import_unusual_file_modes(self, rev, unusual_file_modes):

        if unusual_file_modes:

            ret = [(path, unusual_file_modes[path])

                   for path in sorted(unusual_file_modes.keys())]

            rev.properties['file-modes'] = bencode.bencode(ret)

    def export_unusual_file_modes(self, rev):

        try:

            file_modes = rev.properties['file-modes']

        except KeyError:

            return {}

        else:

            return dict([(self.generate_file_id(path), mode) for (path, mode) in bencode.bdecode(file_modes.encode("utf-8"))])

    def _generate_git_svn_metadata(self, rev, encoding):

        try:

            git_svn_id = rev.properties["git-svn-id"]

        except KeyError:

            return ""

        else:

            return "\ngit-svn-id: %s\n" % git_svn_id.encode(encoding)

    def _generate_hg_message_tail(self, rev):

        extra = {}

        renames = []

        branch = 'default'

        for name in rev.properties:

            if name == 'hg:extra:branch':

                branch = rev.properties['hg:extra:branch']

            elif name.startswith('hg:extra'):

                extra[name[len('hg:extra:'):]] = base64.b64decode(

                    rev.properties[name])

            elif name == 'hg:renames':

                renames = bencode.bdecode(base64.b64decode(

                    rev.properties['hg:renames']))

            # TODO: Export other properties as 'bzr:' extras?

        ret = format_hg_metadata(renames, branch, extra)

        assert isinstance(ret, str)

        return ret

    def _extract_git_svn_metadata(self, rev, message):

        lines = message.split("\n")

        if not (lines[-1] == "" and len(lines) >= 2 and lines[-2].startswith("git-svn-id:")):

            return message

        git_svn_id = lines[-2].split(": ", 1)[1]

        rev.properties['git-svn-id'] = git_svn_id

        (url, rev, uuid) = parse_git_svn_id(git_svn_id)

        # FIXME: Convert this to converted-from property somehow..

        ret = "\n".join(lines[:-2])

        assert isinstance(ret, str)

        return ret

    def _extract_hg_metadata(self, rev, message):

        (message, renames, branch, extra) = extract_hg_metadata(message)

        if branch is not None:

            rev.properties['hg:extra:branch'] = branch

        for name, value in extra.iteritems():

            rev.properties['hg:extra:' + name] = base64.b64encode(value)

        if renames:

            rev.properties['hg:renames'] = base64.b64encode(bencode.bencode(

                [(new, old) for (old, new) in renames.iteritems()]))

        return message

    def _extract_bzr_metadata(self, rev, message):

        (message, metadata) = extract_bzr_metadata(message)

        return message, metadata

    def _decode_commit_message(self, rev, message, encoding):

        return message.decode(encoding), BzrGitRevisionMetadata()

    def _encode_commit_message(self, rev, message, encoding):

        return message.encode(encoding)

    def export_fileid_map(self, fileid_map):

        """Export a file id map to a fileid map.

        :param fileid_map: File id map, mapping paths to file ids

        :return: A Git blob object

        """

        from dulwich.objects import Blob

        b = Blob()

        b.set_raw_chunks(serialize_fileid_map(fileid_map))

        return b

    def export_commit(self, rev, tree_sha, parent_lookup, roundtrip,

                      verifiers):

        """Turn a Bazaar revision in to a Git commit

        :param tree_sha: Tree sha for the commit

        :param parent_lookup: Function for looking up the GIT sha equiv of a

            bzr revision

        :param roundtrip: Whether to store roundtripping information.

        :param verifiers: Verifiers info

        :return dulwich.objects.Commit represent the revision:

        """

        from dulwich.objects import Commit

        commit = Commit()

        commit.tree = tree_sha

        if roundtrip:

            metadata = BzrGitRevisionMetadata()

            metadata.verifiers = verifiers

        else:

            metadata = None

        parents = []

        for p in rev.parent_ids:

            try:

                git_p = parent_lookup(p)

            except KeyError:

                git_p = None

                if metadata is not None:

                    metadata.explicit_parent_ids = rev.parent_ids

            if git_p is not None:

                assert len(git_p) == 40, "unexpected length for %r" % git_p

                parents.append(git_p)

        commit.parents = parents

        try:

            encoding = rev.properties['git-explicit-encoding']

        except KeyError:

            encoding = rev.properties.get('git-implicit-encoding', 'utf-8')

        commit.encoding = rev.properties.get('git-explicit-encoding')

        commit.committer = fix_person_identifier(rev.committer.encode(

            encoding))

        commit.author = fix_person_identifier(

            rev.get_apparent_authors()[0].encode(encoding))

        commit.commit_time = long(rev.timestamp)

        if 'author-timestamp' in rev.properties:

            commit.author_time = long(rev.properties['author-timestamp'])

        else:

            commit.author_time = commit.commit_time

        commit._commit_timezone_neg_utc = "commit-timezone-neg-utc" in rev.properties

        commit.commit_timezone = rev.timezone

        commit._author_timezone_neg_utc = "author-timezone-neg-utc" in rev.properties

        if 'author-timezone' in rev.properties:

            commit.author_timezone = int(rev.properties['author-timezone'])

        else:

            commit.author_timezone = commit.commit_timezone

        commit.message = self._encode_commit_message(rev, rev.message, 

            encoding)

        assert type(commit.message) == str

        if metadata is not None:

            try:

                mapping_registry.parse_revision_id(rev.revision_id)

            except errors.InvalidRevisionId:

                metadata.revision_id = rev.revision_id

            mapping_properties = set(

                ['author', 'author-timezone', 'author-timezone-neg-utc',

                 'commit-timezone-neg-utc', 'git-implicit-encoding',

                 'git-explicit-encoding', 'author-timestamp', 'file-modes'])

            for k, v in rev.properties.iteritems():

                if not k in mapping_properties:

                    metadata.properties[k] = v

        if self.roundtripping:

            commit.message = inject_bzr_metadata(commit.message, metadata, 

                                                 encoding)

        assert type(commit.message) == str

        return commit

    def import_fileid_map(self, blob):

        """Convert a git file id map blob.

        :param blob: Git blob object with fileid map

        :return: Dictionary mapping paths to file ids

        """

        return deserialize_fileid_map(blob.data)

    def import_commit(self, commit, lookup_parent_revid):

        """Convert a git commit to a bzr revision.

        :return: a `bzrlib.revision.Revision` object, foreign revid and a

            testament sha1

        """

        if commit is None:

            raise AssertionError("Commit object can't be None")

        rev = ForeignRevision(commit.id, self,

                self.revision_id_foreign_to_bzr(commit.id))

        rev.git_metadata = None

        def decode_using_encoding(rev, commit, encoding):

            rev.committer = str(commit.committer).decode(encoding)

            if commit.committer != commit.author:

                rev.properties['author'] = str(commit.author).decode(encoding)

            rev.message, rev.git_metadata = self._decode_commit_message(

                rev, commit.message, encoding)

        if commit.encoding is not None:

            rev.properties['git-explicit-encoding'] = commit.encoding

            decode_using_encoding(rev, commit, commit.encoding)

        else:

            for encoding in ('utf-8', 'latin1'):

                try:

                    decode_using_encoding(rev, commit, encoding)

                except UnicodeDecodeError:

                    pass

                else:

                    if encoding != 'utf-8':

                        rev.properties['git-implicit-encoding'] = encoding

                    break

        if commit.commit_time != commit.author_time:

            rev.properties['author-timestamp'] = str(commit.author_time)

        if commit.commit_timezone != commit.author_timezone:

            rev.properties['author-timezone'] = "%d" % commit.author_timezone

        if commit._author_timezone_neg_utc:

            rev.properties['author-timezone-neg-utc'] = ""

        if commit._commit_timezone_neg_utc:

            rev.properties['commit-timezone-neg-utc'] = ""

        rev.timestamp = commit.commit_time

        rev.timezone = commit.commit_timezone

        rev.parent_ids = None

        if rev.git_metadata is not None:

            md = rev.git_metadata

            roundtrip_revid = md.revision_id

            if md.explicit_parent_ids:

                rev.parent_ids = md.explicit_parent_ids

            rev.properties.update(md.properties)

            verifiers = md.verifiers

        else:

            roundtrip_revid = None

            verifiers = {}

        if rev.parent_ids is None:

            rev.parent_ids = tuple([lookup_parent_revid(p) for p in commit.parents])

        return rev, roundtrip_revid, verifiers

    def get_fileid_map(self, lookup_object, tree_sha):

        """Obtain a fileid map for a particular tree.

        :param lookup_object: Function for looking up an object

        :param tree_sha: SHA of the root tree

        :return: GitFileIdMap instance

        """

        try:

            file_id_map_sha = lookup_object(tree_sha)[self.BZR_FILE_IDS_FILE][1]

        except KeyError:

            file_ids = {}

        else:

            file_ids = self.import_fileid_map(lookup_object(file_id_map_sha))

        return GitFileIdMap(file_ids, self)

class BzrGitMappingv1(BzrGitMapping):

    revid_prefix = 'git-v1'

    experimental = False

    def __str__(self):

        return self.revid_prefix

class BzrGitMappingExperimental(BzrGitMappingv1):

    revid_prefix = 'git-experimental'

    experimental = True

    roundtripping = True

    BZR_FILE_IDS_FILE = '.bzrfileids'

    BZR_DUMMY_FILE = '.bzrdummy'

    def _decode_commit_message(self, rev, message, encoding):

        message = self._extract_hg_metadata(rev, message)

        message = self._extract_git_svn_metadata(rev, message)

        message, metadata = self._extract_bzr_metadata(rev, message)

        return message.decode(encoding), metadata

    def _encode_commit_message(self, rev, message, encoding):

        ret = message.encode(encoding)

        ret += self._generate_hg_message_tail(rev)

        ret += self._generate_git_svn_metadata(rev, encoding)

        return ret

    def import_commit(self, commit, lookup_parent_revid):

        rev, roundtrip_revid, verifiers = super(BzrGitMappingExperimental, self).import_commit(commit, lookup_parent_revid)

        rev.properties['converted_revision'] = "git %s\n" % commit.id

        return rev, roundtrip_revid, verifiers

class GitMappingRegistry(VcsMappingRegistry):

    """Registry with available git mappings."""

    def revision_id_bzr_to_foreign(self, bzr_revid):

        if bzr_revid == NULL_REVISION:

            from dulwich.protocol import ZERO_SHA

            return ZERO_SHA, None

        if not bzr_revid.startswith("git-"):

            raise errors.InvalidRevisionId(bzr_revid, None)

        (mapping_version, git_sha) = bzr_revid.split(":", 1)

        mapping = self.get(mapping_version)

        return mapping.revision_id_bzr_to_foreign(bzr_revid)

    parse_revision_id = revision_id_bzr_to_foreign

mapping_registry = GitMappingRegistry()

mapping_registry.register_lazy('git-v1', "bzrlib.plugins.git.mapping",

    "BzrGitMappingv1")

mapping_registry.register_lazy('git-experimental',

    "bzrlib.plugins.git.mapping", "BzrGitMappingExperimental")

mapping_registry.set_default('git-v1')

class ForeignGit(ForeignVcs):

    """The Git Stupid Content Tracker"""

    @property

    def branch_format(self):

        from bzrlib.plugins.git.branch import GitBranchFormat

        return GitBranchFormat()

    @property

    def repository_format(self):

        from bzrlib.plugins.git.repository import GitRepositoryFormat

        return GitRepositoryFormat()

    def __init__(self):

        super(ForeignGit, self).__init__(mapping_registry)

        self.abbreviation = "git"

    @classmethod

    def serialize_foreign_revid(self, foreign_revid):

        return foreign_revid

    @classmethod

    def show_foreign_revid(cls, foreign_revid):

        return { "git commit": foreign_revid }

foreign_git = ForeignGit()

default_mapping = mapping_registry.get_default()()

def symlink_to_blob(entry):

    from dulwich.objects import Blob

    blob = Blob()

    symlink_target = entry.symlink_target

    if type(symlink_target) == unicode:

        symlink_target = symlink_target.encode('utf-8')

    blob.data = symlink_target

    return blob

def mode_is_executable(mode):

    """Check if mode should be considered executable."""

    return bool(mode & 0111)

def mode_kind(mode):

    """Determine the Bazaar inventory kind based on Unix file mode."""

    entry_kind = (mode & 0700000) / 0100000

    if entry_kind == 0:

        return 'directory'

    elif entry_kind == 1:

        file_kind = (mode & 070000) / 010000

        if file_kind == 0:

            return 'file'

        elif file_kind == 2:

            return 'symlink'

        elif file_kind == 6:

            return 'tree-reference'

        else:

            raise AssertionError(

                "Unknown file kind %d, perms=%o." % (file_kind, mode,))

    else:

        raise AssertionError(

            "Unknown kind, perms=%r." % (mode,))

def object_mode(kind, executable):

    if kind == 'directory':

        return stat.S_IFDIR

    elif kind == 'symlink':

        mode = stat.S_IFLNK

        if executable:

            mode |= 0111

        return mode

    elif kind == 'file':

        mode = stat.S_IFREG | 0644

        if executable:

            mode |= 0111

        return mode

    elif kind == 'tree-reference':

        from dulwich.objects import S_IFGITLINK

        return S_IFGITLINK

    else:

        raise AssertionError

def entry_mode(entry):

    """Determine the git file mode for an inventory entry."""

    return object_mode(entry.kind, entry.executable)

def directory_to_tree(entry, lookup_ie_sha1, unusual_modes, empty_file_name):

    """Create a Git Tree object from a Bazaar directory.

    :param entry: Inventory entry

    :param lookup_ie_sha1: Lookup the Git SHA1 for a inventory entry

    :param unusual_modes: Dictionary with unusual file modes by file ids

    :param empty_file_name: Name to use for dummy files in empty directories,

        None to ignore empty directories.

    """

    from dulwich.objects import Blob, Tree

    tree = Tree()

    for name, value in entry.children.iteritems():

        ie = entry.children[name]

        try:

            mode = unusual_modes[ie.file_id]

        except KeyError:

            mode = entry_mode(ie)

        hexsha = lookup_ie_sha1(ie)

        if hexsha is not None:

            tree.add(name.encode("utf-8"), mode, hexsha)

    if entry.parent_id is not None and len(tree) == 0:

        # Only the root can be an empty tree

        if empty_file_name is not None:

            tree.add(empty_file_name, stat.S_IFREG | 0644, Blob().id)

        else:

            return None

    return tree

def extract_unusual_modes(rev):

    try:

        foreign_revid, mapping = mapping_registry.parse_revision_id(

            rev.revision_id)

    except errors.InvalidRevisionId:

        return {}

    else:

        return mapping.export_unusual_file_modes(rev)

def parse_git_svn_id(text):

    (head, uuid) = text.rsplit(" ", 1)

    (full_url, rev) = head.rsplit("@", 1)

    return (full_url, int(rev), uuid)

class GitFileIdMap(object):

    def __init__(self, file_ids, mapping):

        self.file_ids = file_ids

        self.paths = None

        self.mapping = mapping

    def lookup_file_id(self, path):

        assert type(path) is str

        try:

            file_id = self.file_ids[path]

        except KeyError:

            file_id = self.mapping.generate_file_id(path)

        assert type(file_id) is str

        return file_id

    def lookup_path(self, file_id):

        if self.paths is None:

            self.paths = {}

            for k, v in self.file_ids.iteritems():

                self.paths[v] = k

        try:

            path = self.paths[file_id]

        except KeyError:

            return self.mapping.parse_file_id(file_id)

        else:

            assert type(path) is str

            return path