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
38
import thread as _thread
41
from ...lazy_import import lazy_import
32
42
lazy_import(globals(), """
46
from bzrlib.smart import client, protocol, request, vfs
47
from bzrlib.transport import ssh
54
from breezy.i18n import gettext
55
from breezy.bzr.smart import client, protocol, request, signals, vfs
56
from breezy.transport import ssh
49
from bzrlib import osutils
51
63
# Throughout this module buffer size parameters are either limited to be at
52
64
# most _MAX_READ_SIZE, or are ignored and _MAX_READ_SIZE is used instead.
114
137
def __init__(self):
115
138
self._push_back_buffer = None
117
def _push_back(self, bytes):
140
def _push_back(self, data):
118
141
"""Return unused bytes to the medium, because they belong to the next
121
144
This sets the _push_back_buffer to the given bytes.
146
if not isinstance(data, bytes):
147
raise TypeError(data)
123
148
if self._push_back_buffer is not None:
124
149
raise AssertionError(
125
150
"_push_back called when self._push_back_buffer is %r"
126
151
% (self._push_back_buffer,))
129
self._push_back_buffer = bytes
154
self._push_back_buffer = data
131
156
def _get_push_back_buffer(self):
132
if self._push_back_buffer == '':
157
if self._push_back_buffer == b'':
133
158
raise AssertionError(
134
159
'%s._push_back_buffer should never be the empty string, '
135
160
'which can be confused with EOF' % (self,))
214
253
while not self.finished:
215
254
server_protocol = self._build_protocol()
216
255
self._serve_one_request(server_protocol)
256
except errors.ConnectionTimeout as e:
257
trace.note('%s' % (e,))
258
trace.log_exception_quietly()
259
self._disconnect_client()
260
# We reported it, no reason to make a big fuss.
262
except Exception as e:
218
263
stderr.write("%s terminating on exception %s\n" % (self, e))
265
self._disconnect_client()
267
def _stop_gracefully(self):
268
"""When we finish this message, stop looking for more."""
269
trace.mutter('Stopping %s' % (self,))
272
def _disconnect_client(self):
273
"""Close the current connection. We stopped due to a timeout/etc."""
274
# The default implementation is a no-op, because that is all we used to
275
# do when disconnecting from a client. I suppose we never had the
276
# *server* initiate a disconnect, before
278
def _wait_for_bytes_with_timeout(self, timeout_seconds):
279
"""Wait for more bytes to be read, but timeout if none available.
281
This allows us to detect idle connections, and stop trying to read from
282
them, without setting the socket itself to non-blocking. This also
283
allows us to specify when we watch for idle timeouts.
285
:return: Did we timeout? (True if we timed out, False if there is data
288
raise NotImplementedError(self._wait_for_bytes_with_timeout)
221
290
def _build_protocol(self):
222
291
"""Identifies the version of the incoming request, and returns an
234
307
protocol.accept_bytes(unused_bytes)
310
def _wait_on_descriptor(self, fd, timeout_seconds):
311
"""select() on a file descriptor, waiting for nonblocking read()
313
This will raise a ConnectionTimeout exception if we do not get a
314
readable handle before timeout_seconds.
317
t_end = self._timer() + timeout_seconds
318
poll_timeout = min(timeout_seconds, self._client_poll_timeout)
320
while not rs and not xs and self._timer() < t_end:
324
rs, _, xs = select.select([fd], [], [fd], poll_timeout)
325
except (select.error, socket.error) as e:
326
err = getattr(e, 'errno', None)
327
if err is None and getattr(e, 'args', None) is not None:
328
# select.error doesn't have 'errno', it just has args[0]
330
if err in _bad_file_descriptor:
331
return # Not a socket indicates read() will fail
332
elif err == errno.EINTR:
333
# Interrupted, keep looping.
337
return # Socket may already be closed
340
raise errors.ConnectionTimeout('disconnecting client after %.1f seconds'
341
% (timeout_seconds,))
237
343
def _serve_one_request(self, protocol):
238
344
"""Read one request from input, process, send back a response.
240
346
:param protocol: a SmartServerRequestProtocol.
243
351
self._serve_one_request_unguarded(protocol)
244
352
except KeyboardInterrupt:
354
except Exception as e:
247
355
self.terminate_due_to_error()
249
357
def terminate_due_to_error(self):
261
369
class SmartServerSocketStreamMedium(SmartServerStreamMedium):
263
def __init__(self, sock, backing_transport, root_client_path='/'):
371
def __init__(self, sock, backing_transport, root_client_path='/',
266
375
:param sock: the socket the server will read from. It will be put
267
376
into blocking mode.
269
378
SmartServerStreamMedium.__init__(
270
self, backing_transport, root_client_path=root_client_path)
379
self, backing_transport, root_client_path=root_client_path,
271
381
sock.setblocking(True)
272
382
self.socket = sock
383
# Get the getpeername now, as we might be closed later when we care.
385
self._client_info = sock.getpeername()
387
self._client_info = '<unknown>'
390
return '%s(client=%s)' % (self.__class__.__name__, self._client_info)
393
return '%s.%s(client=%s)' % (self.__module__, self.__class__.__name__,
274
396
def _serve_one_request_unguarded(self, protocol):
275
397
while protocol.next_read_size():
277
399
# than MAX_SOCKET_CHUNK ready, the socket will just return a
278
400
# short read immediately rather than block.
279
401
bytes = self.read_bytes(osutils.MAX_SOCKET_CHUNK)
281
403
self.finished = True
283
405
protocol.accept_bytes(bytes)
285
407
self._push_back(protocol.unused_data)
409
def _disconnect_client(self):
410
"""Close the current connection. We stopped due to a timeout/etc."""
413
def _wait_for_bytes_with_timeout(self, timeout_seconds):
414
"""Wait for more bytes to be read, but timeout if none available.
416
This allows us to detect idle connections, and stop trying to read from
417
them, without setting the socket itself to non-blocking. This also
418
allows us to specify when we watch for idle timeouts.
420
:return: None, this will raise ConnectionTimeout if we time out before
423
return self._wait_on_descriptor(self.socket, timeout_seconds)
287
425
def _read_bytes(self, desired_count):
288
426
return osutils.read_bytes_from_socket(
289
427
self.socket, self._report_activity)
295
433
self.finished = True
297
435
def _write_out(self, bytes):
298
tstart = osutils.timer_func()
436
tstart = osutils.perf_counter()
299
437
osutils.send_all(self.socket, bytes, self._report_activity)
300
438
if 'hpss' in debug.debug_flags:
301
thread_id = thread.get_ident()
439
thread_id = _thread.get_ident()
302
440
trace.mutter('%12s: [%s] %d bytes to the socket in %.3fs'
303
441
% ('wrote', thread_id, len(bytes),
304
osutils.timer_func() - tstart))
442
osutils.perf_counter() - tstart))
307
445
class SmartServerPipeStreamMedium(SmartServerStreamMedium):
309
def __init__(self, in_file, out_file, backing_transport):
447
def __init__(self, in_file, out_file, backing_transport, timeout=None):
310
448
"""Construct new server.
312
450
:param in_file: Python file from which requests can be read.
313
451
:param out_file: Python file to write responses.
314
452
:param backing_transport: Transport for the directory served.
316
SmartServerStreamMedium.__init__(self, backing_transport)
454
SmartServerStreamMedium.__init__(self, backing_transport,
317
456
if sys.platform == 'win32':
318
457
# force binary mode for files
335
485
self._out.flush()
337
487
bytes = self.read_bytes(bytes_to_read)
339
489
# Connection has been closed.
340
490
self.finished = True
341
491
self._out.flush()
343
493
protocol.accept_bytes(bytes)
495
def _disconnect_client(self):
500
def _wait_for_bytes_with_timeout(self, timeout_seconds):
501
"""Wait for more bytes to be read, but timeout if none available.
503
This allows us to detect idle connections, and stop trying to read from
504
them, without setting the socket itself to non-blocking. This also
505
allows us to specify when we watch for idle timeouts.
507
:return: None, this will raise ConnectionTimeout if we time out before
510
if (getattr(self._in, 'fileno', None) is None
511
or sys.platform == 'win32'):
512
# You can't select() file descriptors on Windows.
515
return self._wait_on_descriptor(self._in, timeout_seconds)
516
except io.UnsupportedOperation:
345
519
def _read_bytes(self, desired_count):
346
520
return self._in.read(desired_count)
491
665
return self._medium._get_line()
668
class _VfsRefuser(object):
669
"""An object that refuses all VFS requests.
674
client._SmartClient.hooks.install_named_hook(
675
'call', self.check_vfs, 'vfs refuser')
677
def check_vfs(self, params):
679
request_method = request.request_handlers.get(params.method)
681
# A method we don't know about doesn't count as a VFS method.
683
if issubclass(request_method, vfs.VfsRequest):
684
raise HpssVfsRequestNotAllowed(params.method, params.args)
494
687
class _DebugCounter(object):
495
688
"""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
690
When a medium is garbage-collected, or failing that when
691
breezy.global_state exits, the total number of calls made on that medium
692
are reported via trace.note.
502
695
def __init__(self):
503
696
self.counts = weakref.WeakKeyDictionary()
504
697
client._SmartClient.hooks.install_named_hook(
505
698
'call', self.increment_call_count, 'hpss call counter')
506
atexit.register(self.flush_all)
699
breezy.get_global_state().exit_stack.callback(self.flush_all)
508
701
def track(self, medium):
509
702
"""Start tracking calls made to a medium.
602
801
:seealso: _is_remote_before
604
803
if (self._remote_version_is_before is not None and
605
version_tuple > self._remote_version_is_before):
804
version_tuple > self._remote_version_is_before):
606
805
# We have been told that the remote side is older than some version
607
806
# which is newer than a previously supplied older-than version.
608
807
# This indicates that some smart verb call is not guarded
609
808
# appropriately (it should simply not have been tried).
611
810
"_remember_remote_is_before(%r) called, but "
612
"_remember_remote_is_before(%r) was called previously."
613
, version_tuple, self._remote_version_is_before)
811
"_remember_remote_is_before(%r) was called previously.", version_tuple, self._remote_version_is_before)
614
812
if 'hpss' in debug.debug_flags:
615
813
ui.ui_factory.show_warning(
616
814
"_remember_remote_is_before(%r) called, but "
628
826
medium_request = self.get_request()
629
827
# Send a 'hello' request in protocol version one, for maximum
630
828
# backwards compatibility.
631
client_protocol = protocol.SmartClientRequestProtocolOne(medium_request)
829
client_protocol = protocol.SmartClientRequestProtocolOne(
632
831
client_protocol.query_version()
633
832
self._done_hello = True
634
except errors.SmartProtocolError, e:
833
except errors.SmartProtocolError as e:
635
834
# Cache the error, just like we would cache a successful
637
836
self._protocol_version_error = e
711
910
return SmartClientStreamMediumRequest(self)
913
"""We have been disconnected, reset current state.
915
This resets things like _current_request and connected state.
918
self._current_request = None
714
921
class SmartSimplePipesClientMedium(SmartClientStreamMedium):
715
922
"""A client medium using simple pipes.
717
924
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
927
def __init__(self, readable_pipe, writeable_pipe, base):
726
929
self._readable_pipe = readable_pipe
727
930
self._writeable_pipe = writeable_pipe
729
def _accept_bytes(self, bytes):
932
def _accept_bytes(self, data):
730
933
"""See SmartClientStreamMedium.accept_bytes."""
731
self._writeable_pipe.write(bytes)
732
self._report_activity(len(bytes), 'write')
935
self._writeable_pipe.write(data)
937
if e.errno in (errno.EINVAL, errno.EPIPE):
938
raise errors.ConnectionReset(
939
"Error trying to write to subprocess", e)
941
self._report_activity(len(data), 'write')
734
943
def _flush(self):
735
944
"""See SmartClientStreamMedium._flush()."""
945
# Note: If flush were to fail, we'd like to raise ConnectionReset, etc.
946
# However, testing shows that even when the child process is
947
# gone, this doesn't error.
736
948
self._writeable_pipe.flush()
738
950
def _read_bytes(self, count):
739
951
"""See SmartClientStreamMedium._read_bytes."""
740
bytes = osutils.until_no_eintr(self._readable_pipe.read, count)
741
self._report_activity(len(bytes), 'read')
952
bytes_to_read = min(count, _MAX_READ_SIZE)
953
data = self._readable_pipe.read(bytes_to_read)
954
self._report_activity(len(data), 'read')
958
class SSHParams(object):
959
"""A set of parameters for starting a remote bzr via SSH."""
961
def __init__(self, host, port=None, username=None, password=None,
962
bzr_remote_path='bzr'):
965
self.username = username
966
self.password = password
967
self.bzr_remote_path = bzr_remote_path
745
970
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):
971
"""A client medium using SSH.
973
It delegates IO to a SmartSimplePipesClientMedium or
974
SmartClientAlreadyConnectedSocketMedium (depending on platform).
977
def __init__(self, base, ssh_params, vendor=None):
750
978
"""Creates a client that will connect on the first use.
980
:param ssh_params: A SSHParams instance.
752
981
:param vendor: An optional override for the ssh vendor to use. See
753
bzrlib.transport.ssh for details on ssh vendors.
982
breezy.transport.ssh for details on ssh vendors.
755
self._connected = False
757
self._password = password
759
self._username = username
984
self._real_medium = None
985
self._ssh_params = ssh_params
760
986
# for the benefit of progress making a short description of this
762
988
self._scheme = 'bzr+ssh'
764
990
# _DebugCounter so we have to store all the values used in our repr
765
991
# method before calling the super init.
766
992
SmartClientStreamMedium.__init__(self, base)
767
self._read_from = None
993
self._vendor = vendor
768
994
self._ssh_connection = None
769
self._vendor = vendor
770
self._write_to = None
771
self._bzr_remote_path = bzr_remote_path
773
996
def __repr__(self):
774
if self._port is None:
997
if self._ssh_params.port is None:
777
maybe_port = ':%s' % self._port
778
return "%s(%s://%s@%s%s/)" % (
1000
maybe_port = ':%s' % self._ssh_params.port
1001
if self._ssh_params.username is None:
1004
maybe_user = '%s@' % self._ssh_params.username
1005
return "%s(%s://%s%s%s/)" % (
779
1006
self.__class__.__name__,
1009
self._ssh_params.host,
785
1012
def _accept_bytes(self, bytes):
786
1013
"""See SmartClientStreamMedium.accept_bytes."""
787
1014
self._ensure_connection()
788
self._write_to.write(bytes)
789
self._report_activity(len(bytes), 'write')
1015
self._real_medium.accept_bytes(bytes)
791
1017
def disconnect(self):
792
1018
"""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
1019
if self._real_medium is not None:
1020
self._real_medium.disconnect()
1021
self._real_medium = None
1022
if self._ssh_connection is not None:
1023
self._ssh_connection.close()
1024
self._ssh_connection = None
800
1026
def _ensure_connection(self):
801
1027
"""Connect this medium if not already connected."""
1028
if self._real_medium is not None:
804
1030
if self._vendor is None:
805
1031
vendor = ssh._get_ssh_vendor()
807
1033
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',
811
'--directory=/', '--allow-writes'])
812
self._read_from, self._write_to = \
813
self._ssh_connection.get_filelike_channels()
814
self._connected = True
1034
self._ssh_connection = vendor.connect_ssh(self._ssh_params.username,
1035
self._ssh_params.password, self._ssh_params.host,
1036
self._ssh_params.port,
1037
command=[self._ssh_params.bzr_remote_path, 'serve', '--inet',
1038
'--directory=/', '--allow-writes'])
1039
io_kind, io_object = self._ssh_connection.get_sock_or_pipes()
1040
if io_kind == 'socket':
1041
self._real_medium = SmartClientAlreadyConnectedSocketMedium(
1042
self.base, io_object)
1043
elif io_kind == 'pipes':
1044
read_from, write_to = io_object
1045
self._real_medium = SmartSimplePipesClientMedium(
1046
read_from, write_to, self.base)
1048
raise AssertionError(
1049
"Unexpected io_kind %r from %r"
1050
% (io_kind, self._ssh_connection))
1051
for hook in transport.Transport.hooks["post_connect"]:
816
1054
def _flush(self):
817
1055
"""See SmartClientStreamMedium._flush()."""
818
self._write_to.flush()
1056
self._real_medium._flush()
820
1058
def _read_bytes(self, count):
821
1059
"""See SmartClientStreamMedium.read_bytes."""
822
if not self._connected:
1060
if self._real_medium is None:
823
1061
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')
1062
return self._real_medium.read_bytes(count)
830
1065
# Port 4155 is the default port for bzr://, registered with IANA.
832
1067
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."""
1070
class SmartClientSocketMedium(SmartClientStreamMedium):
1071
"""A client medium using a socket.
1073
This class isn't usable directly. Use one of its subclasses instead.
1076
def __init__(self, base):
840
1077
SmartClientStreamMedium.__init__(self, base)
841
1079
self._connected = False
846
1081
def _accept_bytes(self, bytes):
847
1082
"""See SmartClientMedium.accept_bytes."""
848
1083
self._ensure_connection()
849
1084
osutils.send_all(self._socket, bytes, self._report_activity)
1086
def _ensure_connection(self):
1087
"""Connect this medium if not already connected."""
1088
raise NotImplementedError(self._ensure_connection)
1091
"""See SmartClientStreamMedium._flush().
1093
For sockets we do no flushing. For TCP sockets we may want to turn off
1094
TCP_NODELAY and add a means to do a flush, but that can be done in the
1098
def _read_bytes(self, count):
1099
"""See SmartClientMedium.read_bytes."""
1100
if not self._connected:
1101
raise errors.MediumNotConnected(self)
1102
return osutils.read_bytes_from_socket(
1103
self._socket, self._report_activity)
851
1105
def disconnect(self):
852
1106
"""See SmartClientMedium.disconnect()."""
853
1107
if not self._connected:
866
1130
port = int(self._port)
868
1132
sockaddrs = socket.getaddrinfo(self._host, port, socket.AF_UNSPEC,
869
socket.SOCK_STREAM, 0, 0)
870
except socket.gaierror, (err_num, err_msg):
1133
socket.SOCK_STREAM, 0, 0)
1134
except socket.gaierror as xxx_todo_changeme:
1135
(err_num, err_msg) = xxx_todo_changeme.args
871
1136
raise errors.ConnectionError("failed to lookup %s:%d: %s" %
872
(self._host, port, err_msg))
1137
(self._host, port, err_msg))
873
1138
# Initialize err in case there are no addresses returned:
874
err = socket.error("no address found for %s" % self._host)
1139
last_err = socket.error("no address found for %s" % self._host)
875
1140
for (family, socktype, proto, canonname, sockaddr) in sockaddrs:
877
1142
self._socket = socket.socket(family, socktype, proto)
878
1143
self._socket.setsockopt(socket.IPPROTO_TCP,
879
1144
socket.TCP_NODELAY, 1)
880
1145
self._socket.connect(sockaddr)
881
except socket.error, err:
1146
except socket.error as err:
882
1147
if self._socket is not None:
883
1148
self._socket.close()
884
1149
self._socket = None
887
1153
if self._socket is None:
888
1154
# socket errors either have a (string) or (errno, string) as their
890
if type(err.args) is str:
1156
if isinstance(last_err.args, str):
1157
err_msg = last_err.args
893
err_msg = err.args[1]
1159
err_msg = last_err.args[1]
894
1160
raise errors.ConnectionError("failed to connect to %s:%d: %s" %
895
(self._host, port, err_msg))
896
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)
1161
(self._host, port, err_msg))
1162
self._connected = True
1163
for hook in transport.Transport.hooks["post_connect"]:
1167
class SmartClientAlreadyConnectedSocketMedium(SmartClientSocketMedium):
1168
"""A client medium for an already connected socket.
1170
Note that this class will assume it "owns" the socket, so it will close it
1171
when its disconnect method is called.
1174
def __init__(self, base, sock):
1175
SmartClientSocketMedium.__init__(self, base)
1177
self._connected = True
1179
def _ensure_connection(self):
1180
# Already connected, by definition! So nothing to do.
913
1184
class SmartClientStreamMediumRequest(SmartClientMediumRequest):