# 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
"""WSGI application for bzr HTTP smart server.
For more information about WSGI, see PEP 333:
http://www.python.org/dev/peps/pep-0333/
"""
from cStringIO import StringIO
from bzrlib.smart import protocol,medium
from bzrlib.transport import chroot,get_transport
from bzrlib.urlutils import local_path_to_url
def make_app(root, prefix, path_var='REQUEST_URI', readonly=True,
load_plugins=True, enable_logging=True):
"""Convenience function to construct a WSGI bzr smart server.
:param root: a local path that requests will be relative to.
:param prefix: See RelpathSetter.
:param path_var: See RelpathSetter.
"""
local_url = local_path_to_url(root)
if readonly:
base_transport = get_transport('readonly+' + local_url)
else:
base_transport = get_transport(local_url)
if load_plugins:
from bzrlib.plugin import load_plugins
load_plugins()
if enable_logging:
import bzrlib.trace
bzrlib.trace.enable_default_logging()
app = SmartWSGIApp(base_transport, prefix)
app = RelpathSetter(app, '', path_var)
return app
class RelpathSetter(object):
"""WSGI middleware to set 'bzrlib.relpath' in the environ.
Different servers can invoke a SmartWSGIApp in different ways. This
middleware allows an adminstrator to configure how to the SmartWSGIApp will
determine what path it should be serving for a given request for many common
situations.
For example, a request for "/some/prefix/repo/branch/.bzr/smart" received by
a typical Apache and mod_fastcgi configuration will set `REQUEST_URI` to
"/some/prefix/repo/branch/.bzr/smart". A RelpathSetter with
prefix="/some/prefix/" and path_var="REQUEST_URI" will set that request's
'bzrlib.relpath' variable to "repo/branch".
"""
def __init__(self, app, prefix='', path_var='REQUEST_URI'):
"""Constructor.
:param app: WSGI app to wrap, e.g. a SmartWSGIApp instance.
:param path_var: the variable in the WSGI environ to calculate the
'bzrlib.relpath' variable from.
:param prefix: a prefix to strip from the variable specified in
path_var before setting 'bzrlib.relpath'.
"""
self.app = app
self.prefix = prefix
self.path_var = path_var
def __call__(self, environ, start_response):
path = environ[self.path_var]
suffix = '/.bzr/smart'
if not (path.startswith(self.prefix) and path.endswith(suffix)):
start_response('404 Not Found', [])
return []
environ['bzrlib.relpath'] = path[len(self.prefix):-len(suffix)]
return self.app(environ, start_response)
class SmartWSGIApp(object):
"""A WSGI application for the bzr smart server."""
def __init__(self, backing_transport, root_client_path='/'):
"""Constructor.
:param backing_transport: a transport. Requests will be processed
relative to this transport.
:param root_client_path: the client path that maps to the root of
backing_transport. This is used to interpret relpaths received from
the client.
"""
# Use a ChrootTransportDecorator so that this web application won't
# accidentally let people access locations they shouldn't.
# e.g. consider a smart server request for "get /etc/passwd" or
# something.
self.chroot_server = chroot.ChrootServer(backing_transport)
self.chroot_server.start_server()
self.backing_transport = get_transport(self.chroot_server.get_url())
self.root_client_path = root_client_path
# While the chroot server can technically be torn down at this point,
# as all it does is remove the scheme registration from transport's
# protocol dictionary, we don't *just in case* there are parts of
# bzrlib that will invoke 'get_transport' on urls rather than cloning
# around the existing transport.
#self.chroot_server.stop_server()
def __call__(self, environ, start_response):
"""WSGI application callable."""
if environ['REQUEST_METHOD'] != 'POST':
start_response('405 Method not allowed', [('Allow', 'POST')])
return []
relpath = environ['bzrlib.relpath']
if not relpath.startswith('/'):
relpath = '/' + relpath
if not relpath.endswith('/'):
relpath += '/'
# Compare the HTTP path (relpath) and root_client_path, and calculate
# new relpath and root_client_path accordingly, to be used to build the
# request.
if relpath.startswith(self.root_client_path):
# The relpath traverses all of the mandatory root client path.
# Remove the root_client_path from the relpath, and set
# adjusted_tcp to None to tell the request handler that no further
# path translation is required.
adjusted_rcp = None
adjusted_relpath = relpath[len(self.root_client_path):]
elif self.root_client_path.startswith(relpath):
# The relpath traverses some of the mandatory root client path.
# Subtract the relpath from the root_client_path, and set the
# relpath to '.'.
adjusted_rcp = '/' + self.root_client_path[len(relpath):]
adjusted_relpath = '.'
else:
adjusted_rcp = self.root_client_path
adjusted_relpath = relpath
if adjusted_relpath.startswith('/'):
adjusted_relpath = adjusted_relpath[1:]
if adjusted_relpath.startswith('/'):
raise AssertionError(adjusted_relpath)
transport = self.backing_transport.clone(adjusted_relpath)
out_buffer = StringIO()
request_data_length = int(environ['CONTENT_LENGTH'])
request_data_bytes = environ['wsgi.input'].read(request_data_length)
smart_protocol_request = self.make_request(
transport, out_buffer.write, request_data_bytes, adjusted_rcp)
if smart_protocol_request.next_read_size() != 0:
# The request appears to be incomplete, or perhaps it's just a
# newer version we don't understand. Regardless, all we can do
# is return an error response in the format of our version of the
# protocol.
response_data = 'error\x01incomplete request\n'
else:
response_data = out_buffer.getvalue()
headers = [('Content-type', 'application/octet-stream')]
headers.append(("Content-Length", str(len(response_data))))
start_response('200 OK', headers)
return [response_data]
def make_request(self, transport, write_func, request_bytes, rcp):
protocol_factory, unused_bytes = medium._get_protocol_factory_for_bytes(
request_bytes)
server_protocol = protocol_factory(
transport, write_func, rcp, self.backing_transport)
server_protocol.accept_bytes(unused_bytes)
return server_protocol
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