22
22
Media carry the bytes of the requests somehow (e.g. via TCP, wrapped in HTTP, or
23
23
over SSH), and pass them to and from the protocol logic. See the overview in
24
bzrlib/transport/smart/__init__.py.
24
breezy/transport/smart/__init__.py.
27
from __future__ import absolute_import
31
from bzrlib.lazy_import import lazy_import
36
from ...lazy_import import lazy_import
32
37
lazy_import(globals(), """
46
from bzrlib.smart import client, protocol, request, vfs
47
from bzrlib.transport import ssh
50
from breezy.i18n import gettext
51
from breezy.bzr.smart import client, protocol, request, signals, vfs
52
from breezy.transport import ssh
49
from bzrlib import osutils
51
59
# Throughout this module buffer size parameters are either limited to be at
52
60
# most _MAX_READ_SIZE, or are ignored and _MAX_READ_SIZE is used instead.
54
62
# from non-sockets as well.
55
63
_MAX_READ_SIZE = osutils.MAX_SOCKET_CHUNK
66
class HpssVfsRequestNotAllowed(errors.BzrError):
68
_fmt = ("VFS requests over the smart server are not allowed. Encountered: "
69
"%(method)s, %(arguments)s.")
71
def __init__(self, method, arguments):
73
self.arguments = arguments
57
76
def _get_protocol_factory_for_bytes(bytes):
58
77
"""Determine the right protocol factory for 'bytes'.
114
133
def __init__(self):
115
134
self._push_back_buffer = None
117
def _push_back(self, bytes):
136
def _push_back(self, data):
118
137
"""Return unused bytes to the medium, because they belong to the next
121
140
This sets the _push_back_buffer to the given bytes.
142
if not isinstance(data, bytes):
143
raise TypeError(data)
123
144
if self._push_back_buffer is not None:
124
145
raise AssertionError(
125
146
"_push_back called when self._push_back_buffer is %r"
126
147
% (self._push_back_buffer,))
129
self._push_back_buffer = bytes
150
self._push_back_buffer = data
131
152
def _get_push_back_buffer(self):
132
if self._push_back_buffer == '':
153
if self._push_back_buffer == b'':
133
154
raise AssertionError(
134
155
'%s._push_back_buffer should never be the empty string, '
135
156
'which can be confused with EOF' % (self,))
214
249
while not self.finished:
215
250
server_protocol = self._build_protocol()
216
251
self._serve_one_request(server_protocol)
252
except errors.ConnectionTimeout as e:
253
trace.note('%s' % (e,))
254
trace.log_exception_quietly()
255
self._disconnect_client()
256
# We reported it, no reason to make a big fuss.
258
except Exception as e:
218
259
stderr.write("%s terminating on exception %s\n" % (self, e))
261
self._disconnect_client()
263
def _stop_gracefully(self):
264
"""When we finish this message, stop looking for more."""
265
trace.mutter('Stopping %s' % (self,))
268
def _disconnect_client(self):
269
"""Close the current connection. We stopped due to a timeout/etc."""
270
# The default implementation is a no-op, because that is all we used to
271
# do when disconnecting from a client. I suppose we never had the
272
# *server* initiate a disconnect, before
274
def _wait_for_bytes_with_timeout(self, timeout_seconds):
275
"""Wait for more bytes to be read, but timeout if none available.
277
This allows us to detect idle connections, and stop trying to read from
278
them, without setting the socket itself to non-blocking. This also
279
allows us to specify when we watch for idle timeouts.
281
:return: Did we timeout? (True if we timed out, False if there is data
284
raise NotImplementedError(self._wait_for_bytes_with_timeout)
221
286
def _build_protocol(self):
222
287
"""Identifies the version of the incoming request, and returns an
234
303
protocol.accept_bytes(unused_bytes)
306
def _wait_on_descriptor(self, fd, timeout_seconds):
307
"""select() on a file descriptor, waiting for nonblocking read()
309
This will raise a ConnectionTimeout exception if we do not get a
310
readable handle before timeout_seconds.
313
t_end = self._timer() + timeout_seconds
314
poll_timeout = min(timeout_seconds, self._client_poll_timeout)
316
while not rs and not xs and self._timer() < t_end:
320
rs, _, xs = select.select([fd], [], [fd], poll_timeout)
321
except (select.error, socket.error) as e:
322
err = getattr(e, 'errno', None)
323
if err is None and getattr(e, 'args', None) is not None:
324
# select.error doesn't have 'errno', it just has args[0]
326
if err in _bad_file_descriptor:
327
return # Not a socket indicates read() will fail
328
elif err == errno.EINTR:
329
# Interrupted, keep looping.
333
return # Socket may already be closed
336
raise errors.ConnectionTimeout('disconnecting client after %.1f seconds'
337
% (timeout_seconds,))
237
339
def _serve_one_request(self, protocol):
238
340
"""Read one request from input, process, send back a response.
240
342
:param protocol: a SmartServerRequestProtocol.
243
347
self._serve_one_request_unguarded(protocol)
244
348
except KeyboardInterrupt:
350
except Exception as e:
247
351
self.terminate_due_to_error()
249
353
def terminate_due_to_error(self):
261
365
class SmartServerSocketStreamMedium(SmartServerStreamMedium):
263
def __init__(self, sock, backing_transport, root_client_path='/'):
367
def __init__(self, sock, backing_transport, root_client_path='/',
266
371
:param sock: the socket the server will read from. It will be put
267
372
into blocking mode.
269
374
SmartServerStreamMedium.__init__(
270
self, backing_transport, root_client_path=root_client_path)
375
self, backing_transport, root_client_path=root_client_path,
271
377
sock.setblocking(True)
272
378
self.socket = sock
379
# Get the getpeername now, as we might be closed later when we care.
381
self._client_info = sock.getpeername()
383
self._client_info = '<unknown>'
386
return '%s(client=%s)' % (self.__class__.__name__, self._client_info)
389
return '%s.%s(client=%s)' % (self.__module__, self.__class__.__name__,
274
392
def _serve_one_request_unguarded(self, protocol):
275
393
while protocol.next_read_size():
277
395
# than MAX_SOCKET_CHUNK ready, the socket will just return a
278
396
# short read immediately rather than block.
279
397
bytes = self.read_bytes(osutils.MAX_SOCKET_CHUNK)
281
399
self.finished = True
283
401
protocol.accept_bytes(bytes)
285
403
self._push_back(protocol.unused_data)
405
def _disconnect_client(self):
406
"""Close the current connection. We stopped due to a timeout/etc."""
409
def _wait_for_bytes_with_timeout(self, timeout_seconds):
410
"""Wait for more bytes to be read, but timeout if none available.
412
This allows us to detect idle connections, and stop trying to read from
413
them, without setting the socket itself to non-blocking. This also
414
allows us to specify when we watch for idle timeouts.
416
:return: None, this will raise ConnectionTimeout if we time out before
419
return self._wait_on_descriptor(self.socket, timeout_seconds)
287
421
def _read_bytes(self, desired_count):
288
422
return osutils.read_bytes_from_socket(
289
423
self.socket, self._report_activity)
307
441
class SmartServerPipeStreamMedium(SmartServerStreamMedium):
309
def __init__(self, in_file, out_file, backing_transport):
443
def __init__(self, in_file, out_file, backing_transport, timeout=None):
310
444
"""Construct new server.
312
446
:param in_file: Python file from which requests can be read.
313
447
:param out_file: Python file to write responses.
314
448
:param backing_transport: Transport for the directory served.
316
SmartServerStreamMedium.__init__(self, backing_transport)
450
SmartServerStreamMedium.__init__(self, backing_transport,
317
452
if sys.platform == 'win32':
318
453
# force binary mode for files
335
481
self._out.flush()
337
483
bytes = self.read_bytes(bytes_to_read)
339
485
# Connection has been closed.
340
486
self.finished = True
341
487
self._out.flush()
343
489
protocol.accept_bytes(bytes)
491
def _disconnect_client(self):
496
def _wait_for_bytes_with_timeout(self, timeout_seconds):
497
"""Wait for more bytes to be read, but timeout if none available.
499
This allows us to detect idle connections, and stop trying to read from
500
them, without setting the socket itself to non-blocking. This also
501
allows us to specify when we watch for idle timeouts.
503
:return: None, this will raise ConnectionTimeout if we time out before
506
if (getattr(self._in, 'fileno', None) is None
507
or sys.platform == 'win32'):
508
# You can't select() file descriptors on Windows.
511
return self._wait_on_descriptor(self._in, timeout_seconds)
512
except io.UnsupportedOperation:
345
515
def _read_bytes(self, desired_count):
346
516
return self._in.read(desired_count)
491
661
return self._medium._get_line()
664
class _VfsRefuser(object):
665
"""An object that refuses all VFS requests.
670
client._SmartClient.hooks.install_named_hook(
671
'call', self.check_vfs, 'vfs refuser')
673
def check_vfs(self, params):
675
request_method = request.request_handlers.get(params.method)
677
# A method we don't know about doesn't count as a VFS method.
679
if issubclass(request_method, vfs.VfsRequest):
680
raise HpssVfsRequestNotAllowed(params.method, params.args)
494
683
class _DebugCounter(object):
495
684
"""An object that counts the HPSS calls made to each client medium.
497
When a medium is garbage-collected, or failing that when atexit functions
498
are run, the total number of calls made on that medium are reported via
686
When a medium is garbage-collected, or failing that when
687
breezy.global_state exits, the total number of calls made on that medium
688
are reported via trace.note.
502
691
def __init__(self):
503
692
self.counts = weakref.WeakKeyDictionary()
504
693
client._SmartClient.hooks.install_named_hook(
505
694
'call', self.increment_call_count, 'hpss call counter')
506
atexit.register(self.flush_all)
695
breezy.get_global_state().cleanups.add_cleanup(self.flush_all)
508
697
def track(self, medium):
509
698
"""Start tracking calls made to a medium.
711
905
return SmartClientStreamMediumRequest(self)
908
"""We have been disconnected, reset current state.
910
This resets things like _current_request and connected state.
913
self._current_request = None
714
916
class SmartSimplePipesClientMedium(SmartClientStreamMedium):
715
917
"""A client medium using simple pipes.
717
919
This client does not manage the pipes: it assumes they will always be open.
719
Note that if readable_pipe.read might raise IOError or OSError with errno
720
of EINTR, it must be safe to retry the read. Plain CPython fileobjects
721
(such as used for sys.stdin) are safe.
724
922
def __init__(self, readable_pipe, writeable_pipe, base):
726
924
self._readable_pipe = readable_pipe
727
925
self._writeable_pipe = writeable_pipe
729
def _accept_bytes(self, bytes):
927
def _accept_bytes(self, data):
730
928
"""See SmartClientStreamMedium.accept_bytes."""
731
self._writeable_pipe.write(bytes)
732
self._report_activity(len(bytes), 'write')
930
self._writeable_pipe.write(data)
932
if e.errno in (errno.EINVAL, errno.EPIPE):
933
raise errors.ConnectionReset(
934
"Error trying to write to subprocess", e)
936
self._report_activity(len(data), 'write')
734
938
def _flush(self):
735
939
"""See SmartClientStreamMedium._flush()."""
940
# Note: If flush were to fail, we'd like to raise ConnectionReset, etc.
941
# However, testing shows that even when the child process is
942
# gone, this doesn't error.
736
943
self._writeable_pipe.flush()
738
945
def _read_bytes(self, count):
739
946
"""See SmartClientStreamMedium._read_bytes."""
740
bytes = osutils.until_no_eintr(self._readable_pipe.read, count)
741
self._report_activity(len(bytes), 'read')
947
bytes_to_read = min(count, _MAX_READ_SIZE)
948
data = self._readable_pipe.read(bytes_to_read)
949
self._report_activity(len(data), 'read')
953
class SSHParams(object):
954
"""A set of parameters for starting a remote bzr via SSH."""
956
def __init__(self, host, port=None, username=None, password=None,
957
bzr_remote_path='bzr'):
960
self.username = username
961
self.password = password
962
self.bzr_remote_path = bzr_remote_path
745
965
class SmartSSHClientMedium(SmartClientStreamMedium):
746
"""A client medium using SSH."""
748
def __init__(self, host, port=None, username=None, password=None,
749
base=None, vendor=None, bzr_remote_path=None):
966
"""A client medium using SSH.
968
It delegates IO to a SmartSimplePipesClientMedium or
969
SmartClientAlreadyConnectedSocketMedium (depending on platform).
972
def __init__(self, base, ssh_params, vendor=None):
750
973
"""Creates a client that will connect on the first use.
975
:param ssh_params: A SSHParams instance.
752
976
:param vendor: An optional override for the ssh vendor to use. See
753
bzrlib.transport.ssh for details on ssh vendors.
977
breezy.transport.ssh for details on ssh vendors.
755
self._connected = False
757
self._password = password
759
self._username = username
979
self._real_medium = None
980
self._ssh_params = ssh_params
760
981
# for the benefit of progress making a short description of this
762
983
self._scheme = 'bzr+ssh'
764
985
# _DebugCounter so we have to store all the values used in our repr
765
986
# method before calling the super init.
766
987
SmartClientStreamMedium.__init__(self, base)
767
self._read_from = None
988
self._vendor = vendor
768
989
self._ssh_connection = None
769
self._vendor = vendor
770
self._write_to = None
771
self._bzr_remote_path = bzr_remote_path
773
991
def __repr__(self):
774
if self._port is None:
992
if self._ssh_params.port is None:
777
maybe_port = ':%s' % self._port
778
return "%s(%s://%s@%s%s/)" % (
995
maybe_port = ':%s' % self._ssh_params.port
996
if self._ssh_params.username is None:
999
maybe_user = '%s@' % self._ssh_params.username
1000
return "%s(%s://%s%s%s/)" % (
779
1001
self.__class__.__name__,
1004
self._ssh_params.host,
785
1007
def _accept_bytes(self, bytes):
786
1008
"""See SmartClientStreamMedium.accept_bytes."""
787
1009
self._ensure_connection()
788
self._write_to.write(bytes)
789
self._report_activity(len(bytes), 'write')
1010
self._real_medium.accept_bytes(bytes)
791
1012
def disconnect(self):
792
1013
"""See SmartClientMedium.disconnect()."""
793
if not self._connected:
795
self._read_from.close()
796
self._write_to.close()
797
self._ssh_connection.close()
798
self._connected = False
1014
if self._real_medium is not None:
1015
self._real_medium.disconnect()
1016
self._real_medium = None
1017
if self._ssh_connection is not None:
1018
self._ssh_connection.close()
1019
self._ssh_connection = None
800
1021
def _ensure_connection(self):
801
1022
"""Connect this medium if not already connected."""
1023
if self._real_medium is not None:
804
1025
if self._vendor is None:
805
1026
vendor = ssh._get_ssh_vendor()
807
1028
vendor = self._vendor
808
self._ssh_connection = vendor.connect_ssh(self._username,
809
self._password, self._host, self._port,
810
command=[self._bzr_remote_path, 'serve', '--inet',
1029
self._ssh_connection = vendor.connect_ssh(self._ssh_params.username,
1030
self._ssh_params.password, self._ssh_params.host,
1031
self._ssh_params.port,
1032
command=[self._ssh_params.bzr_remote_path, 'serve', '--inet',
811
1033
'--directory=/', '--allow-writes'])
812
self._read_from, self._write_to = \
813
self._ssh_connection.get_filelike_channels()
814
self._connected = True
1034
io_kind, io_object = self._ssh_connection.get_sock_or_pipes()
1035
if io_kind == 'socket':
1036
self._real_medium = SmartClientAlreadyConnectedSocketMedium(
1037
self.base, io_object)
1038
elif io_kind == 'pipes':
1039
read_from, write_to = io_object
1040
self._real_medium = SmartSimplePipesClientMedium(
1041
read_from, write_to, self.base)
1043
raise AssertionError(
1044
"Unexpected io_kind %r from %r"
1045
% (io_kind, self._ssh_connection))
1046
for hook in transport.Transport.hooks["post_connect"]:
816
1049
def _flush(self):
817
1050
"""See SmartClientStreamMedium._flush()."""
818
self._write_to.flush()
1051
self._real_medium._flush()
820
1053
def _read_bytes(self, count):
821
1054
"""See SmartClientStreamMedium.read_bytes."""
822
if not self._connected:
1055
if self._real_medium is None:
823
1056
raise errors.MediumNotConnected(self)
824
bytes_to_read = min(count, _MAX_READ_SIZE)
825
bytes = self._read_from.read(bytes_to_read)
826
self._report_activity(len(bytes), 'read')
1057
return self._real_medium.read_bytes(count)
830
1060
# Port 4155 is the default port for bzr://, registered with IANA.
832
1062
BZR_DEFAULT_PORT = 4155
835
class SmartTCPClientMedium(SmartClientStreamMedium):
836
"""A client medium using TCP."""
838
def __init__(self, host, port, base):
839
"""Creates a client that will connect on the first use."""
1065
class SmartClientSocketMedium(SmartClientStreamMedium):
1066
"""A client medium using a socket.
1068
This class isn't usable directly. Use one of its subclasses instead.
1071
def __init__(self, base):
840
1072
SmartClientStreamMedium.__init__(self, base)
841
1074
self._connected = False
846
1076
def _accept_bytes(self, bytes):
847
1077
"""See SmartClientMedium.accept_bytes."""
848
1078
self._ensure_connection()
849
1079
osutils.send_all(self._socket, bytes, self._report_activity)
1081
def _ensure_connection(self):
1082
"""Connect this medium if not already connected."""
1083
raise NotImplementedError(self._ensure_connection)
1086
"""See SmartClientStreamMedium._flush().
1088
For sockets we do no flushing. For TCP sockets we may want to turn off
1089
TCP_NODELAY and add a means to do a flush, but that can be done in the
1093
def _read_bytes(self, count):
1094
"""See SmartClientMedium.read_bytes."""
1095
if not self._connected:
1096
raise errors.MediumNotConnected(self)
1097
return osutils.read_bytes_from_socket(
1098
self._socket, self._report_activity)
851
1100
def disconnect(self):
852
1101
"""See SmartClientMedium.disconnect()."""
853
1102
if not self._connected:
868
1127
sockaddrs = socket.getaddrinfo(self._host, port, socket.AF_UNSPEC,
869
1128
socket.SOCK_STREAM, 0, 0)
870
except socket.gaierror, (err_num, err_msg):
1129
except socket.gaierror as xxx_todo_changeme:
1130
(err_num, err_msg) = xxx_todo_changeme.args
871
1131
raise errors.ConnectionError("failed to lookup %s:%d: %s" %
872
1132
(self._host, port, err_msg))
873
1133
# Initialize err in case there are no addresses returned:
874
err = socket.error("no address found for %s" % self._host)
1134
last_err = socket.error("no address found for %s" % self._host)
875
1135
for (family, socktype, proto, canonname, sockaddr) in sockaddrs:
877
1137
self._socket = socket.socket(family, socktype, proto)
878
1138
self._socket.setsockopt(socket.IPPROTO_TCP,
879
1139
socket.TCP_NODELAY, 1)
880
1140
self._socket.connect(sockaddr)
881
except socket.error, err:
1141
except socket.error as err:
882
1142
if self._socket is not None:
883
1143
self._socket.close()
884
1144
self._socket = None
887
1148
if self._socket is None:
888
1149
# socket errors either have a (string) or (errno, string) as their
890
if type(err.args) is str:
1151
if isinstance(last_err.args, str):
1152
err_msg = last_err.args
893
err_msg = err.args[1]
1154
err_msg = last_err.args[1]
894
1155
raise errors.ConnectionError("failed to connect to %s:%d: %s" %
895
1156
(self._host, port, err_msg))
896
1157
self._connected = True
899
"""See SmartClientStreamMedium._flush().
901
For TCP we do no flushing. We may want to turn off TCP_NODELAY and
902
add a means to do a flush, but that can be done in the future.
905
def _read_bytes(self, count):
906
"""See SmartClientMedium.read_bytes."""
907
if not self._connected:
908
raise errors.MediumNotConnected(self)
909
return osutils.read_bytes_from_socket(
910
self._socket, self._report_activity)
1158
for hook in transport.Transport.hooks["post_connect"]:
1162
class SmartClientAlreadyConnectedSocketMedium(SmartClientSocketMedium):
1163
"""A client medium for an already connected socket.
1165
Note that this class will assume it "owns" the socket, so it will close it
1166
when its disconnect method is called.
1169
def __init__(self, base, sock):
1170
SmartClientSocketMedium.__init__(self, base)
1172
self._connected = True
1174
def _ensure_connection(self):
1175
# Already connected, by definition! So nothing to do.
913
1179
class SmartClientStreamMediumRequest(SmartClientMediumRequest):