~bzr-pqm/bzr/bzr.dev

# Copyright (C) 2006-2010 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

"""VFS operations for the smart server.

This module defines the smart server methods that are low-level file operations

-- i.e. methods that operate directly on files and directories, rather than

higher-level concepts like branches and revisions.

These methods, plus 'hello' and 'get_bundle', are version 1 of the smart server

protocol, as implemented in bzr 0.11 and later.

"""

from __future__ import absolute_import

import os

from bzrlib import errors

from bzrlib import urlutils

from bzrlib.smart import request

def _deserialise_optional_mode(mode):

    # XXX: FIXME this should be on the protocol object.  Later protocol versions

    # might serialise modes differently.

    if mode == '':

        return None

    else:

        return int(mode)

def vfs_enabled():

    """Is the VFS enabled ?

    the VFS is disabled when the BZR_NO_SMART_VFS environment variable is set.

    :return: True if it is enabled.

    """

    return not 'BZR_NO_SMART_VFS' in os.environ

class VfsRequest(request.SmartServerRequest):

    """Base class for VFS requests.

    VFS requests are disabled if vfs_enabled() returns False.

    """

    def _check_enabled(self):

        if not vfs_enabled():

            raise errors.DisabledMethod(self.__class__.__name__)

    def translate_client_path(self, relpath):

        # VFS requests are made with escaped paths so the escaping done in

        # SmartServerRequest.translate_client_path leads to double escaping.

        # Remove it here -- the fact that the result is still escaped means

        # that the str() will not fail on valid input.

        x = request.SmartServerRequest.translate_client_path(self, relpath)

        return str(urlutils.unescape(x))

class HasRequest(VfsRequest):

    def do(self, relpath):

        relpath = self.translate_client_path(relpath)

        r = self._backing_transport.has(relpath) and 'yes' or 'no'

        return request.SuccessfulSmartServerResponse((r,))

class GetRequest(VfsRequest):

    def do(self, relpath):

        relpath = self.translate_client_path(relpath)

        backing_bytes = self._backing_transport.get_bytes(relpath)

        return request.SuccessfulSmartServerResponse(('ok',), backing_bytes)

class AppendRequest(VfsRequest):

    def do(self, relpath, mode):

        relpath = self.translate_client_path(relpath)

        self._relpath = relpath

        self._mode = _deserialise_optional_mode(mode)

    def do_body(self, body_bytes):

        old_length = self._backing_transport.append_bytes(

            self._relpath, body_bytes, self._mode)

        return request.SuccessfulSmartServerResponse(('appended', '%d' % old_length))

class DeleteRequest(VfsRequest):

    def do(self, relpath):

        relpath = self.translate_client_path(relpath)

        self._backing_transport.delete(relpath)

        return request.SuccessfulSmartServerResponse(('ok', ))

class IterFilesRecursiveRequest(VfsRequest):

    def do(self, relpath):

        if not relpath.endswith('/'):

            relpath += '/'

        relpath = self.translate_client_path(relpath)

        transport = self._backing_transport.clone(relpath)

        filenames = transport.iter_files_recursive()

        return request.SuccessfulSmartServerResponse(('names',) + tuple(filenames))

class ListDirRequest(VfsRequest):

    def do(self, relpath):

        if not relpath.endswith('/'):

            relpath += '/'

        relpath = self.translate_client_path(relpath)

        filenames = self._backing_transport.list_dir(relpath)

        return request.SuccessfulSmartServerResponse(('names',) + tuple(filenames))

class MkdirRequest(VfsRequest):

    def do(self, relpath, mode):

        relpath = self.translate_client_path(relpath)

        self._backing_transport.mkdir(relpath,

                                      _deserialise_optional_mode(mode))

        return request.SuccessfulSmartServerResponse(('ok',))

class MoveRequest(VfsRequest):

    def do(self, rel_from, rel_to):

        rel_from = self.translate_client_path(rel_from)

        rel_to = self.translate_client_path(rel_to)

        self._backing_transport.move(rel_from, rel_to)

        return request.SuccessfulSmartServerResponse(('ok',))

class PutRequest(VfsRequest):

    def do(self, relpath, mode):

        relpath = self.translate_client_path(relpath)

        self._relpath = relpath

        self._mode = _deserialise_optional_mode(mode)

    def do_body(self, body_bytes):

        self._backing_transport.put_bytes(self._relpath, body_bytes, self._mode)

        return request.SuccessfulSmartServerResponse(('ok',))

class PutNonAtomicRequest(VfsRequest):

    def do(self, relpath, mode, create_parent, dir_mode):

        relpath = self.translate_client_path(relpath)

        self._relpath = relpath

        self._dir_mode = _deserialise_optional_mode(dir_mode)

        self._mode = _deserialise_optional_mode(mode)

        # a boolean would be nicer XXX

        self._create_parent = (create_parent == 'T')

    def do_body(self, body_bytes):

        self._backing_transport.put_bytes_non_atomic(self._relpath,

                body_bytes,

                mode=self._mode,

                create_parent_dir=self._create_parent,

                dir_mode=self._dir_mode)

        return request.SuccessfulSmartServerResponse(('ok',))

class ReadvRequest(VfsRequest):

    def do(self, relpath):

        relpath = self.translate_client_path(relpath)

        self._relpath = relpath

    def do_body(self, body_bytes):

        """accept offsets for a readv request."""

        offsets = self._deserialise_offsets(body_bytes)

        backing_bytes = ''.join(bytes for offset, bytes in

            self._backing_transport.readv(self._relpath, offsets))

        return request.SuccessfulSmartServerResponse(('readv',), backing_bytes)

    def _deserialise_offsets(self, text):

        # XXX: FIXME this should be on the protocol object.

        offsets = []

        for line in text.split('\n'):

            if not line:

                continue

            start, length = line.split(',')

            offsets.append((int(start), int(length)))

        return offsets

class RenameRequest(VfsRequest):

    def do(self, rel_from, rel_to):

        rel_from = self.translate_client_path(rel_from)

        rel_to = self.translate_client_path(rel_to)

        self._backing_transport.rename(rel_from, rel_to)

        return request.SuccessfulSmartServerResponse(('ok', ))

class RmdirRequest(VfsRequest):

    def do(self, relpath):

        relpath = self.translate_client_path(relpath)

        self._backing_transport.rmdir(relpath)

        return request.SuccessfulSmartServerResponse(('ok', ))

class StatRequest(VfsRequest):

    def do(self, relpath):

        if not relpath.endswith('/'):

            relpath += '/'

        relpath = self.translate_client_path(relpath)

        stat = self._backing_transport.stat(relpath)

        return request.SuccessfulSmartServerResponse(

            ('stat', str(stat.st_size), oct(stat.st_mode)))