31
from bzrlib.lazy_import import lazy_import
32
lazy_import(globals(), """
46
from bzrlib.smart import client, protocol, request, vfs
47
from bzrlib.transport import ssh
49
from bzrlib import osutils
51
# Throughout this module buffer size parameters are either limited to be at
52
# most _MAX_READ_SIZE, or are ignored and _MAX_READ_SIZE is used instead.
53
# For this module's purposes, MAX_SOCKET_CHUNK is a reasonable size for reads
54
# from non-sockets as well.
55
_MAX_READ_SIZE = osutils.MAX_SOCKET_CHUNK
57
def _get_protocol_factory_for_bytes(bytes):
58
"""Determine the right protocol factory for 'bytes'.
60
This will return an appropriate protocol factory depending on the version
61
of the protocol being used, as determined by inspecting the given bytes.
62
The bytes should have at least one newline byte (i.e. be a whole line),
63
otherwise it's possible that a request will be incorrectly identified as
66
Typical use would be::
68
factory, unused_bytes = _get_protocol_factory_for_bytes(bytes)
69
server_protocol = factory(transport, write_func, root_client_path)
70
server_protocol.accept_bytes(unused_bytes)
72
:param bytes: a str of bytes of the start of the request.
73
:returns: 2-tuple of (protocol_factory, unused_bytes). protocol_factory is
74
a callable that takes three args: transport, write_func,
75
root_client_path. unused_bytes are any bytes that were not part of a
76
protocol version marker.
78
if bytes.startswith(protocol.MESSAGE_VERSION_THREE):
79
protocol_factory = protocol.build_server_protocol_three
80
bytes = bytes[len(protocol.MESSAGE_VERSION_THREE):]
81
elif bytes.startswith(protocol.REQUEST_VERSION_TWO):
82
protocol_factory = protocol.SmartServerRequestProtocolTwo
83
bytes = bytes[len(protocol.REQUEST_VERSION_TWO):]
85
protocol_factory = protocol.SmartServerRequestProtocolOne
86
return protocol_factory, bytes
89
def _get_line(read_bytes_func):
90
"""Read bytes using read_bytes_func until a newline byte.
92
This isn't particularly efficient, so should only be used when the
93
expected size of the line is quite short.
95
:returns: a tuple of two strs: (line, excess)
99
while newline_pos == -1:
100
new_bytes = read_bytes_func(1)
103
# Ran out of bytes before receiving a complete line.
105
newline_pos = bytes.find('\n')
106
line = bytes[:newline_pos+1]
107
excess = bytes[newline_pos+1:]
111
class SmartMedium(object):
112
"""Base class for smart protocol media, both client- and server-side."""
115
self._push_back_buffer = None
117
def _push_back(self, bytes):
118
"""Return unused bytes to the medium, because they belong to the next
121
This sets the _push_back_buffer to the given bytes.
123
if self._push_back_buffer is not None:
124
raise AssertionError(
125
"_push_back called when self._push_back_buffer is %r"
126
% (self._push_back_buffer,))
129
self._push_back_buffer = bytes
131
def _get_push_back_buffer(self):
132
if self._push_back_buffer == '':
133
raise AssertionError(
134
'%s._push_back_buffer should never be the empty string, '
135
'which can be confused with EOF' % (self,))
136
bytes = self._push_back_buffer
137
self._push_back_buffer = None
140
def read_bytes(self, desired_count):
141
"""Read some bytes from this medium.
143
:returns: some bytes, possibly more or less than the number requested
144
in 'desired_count' depending on the medium.
146
if self._push_back_buffer is not None:
147
return self._get_push_back_buffer()
148
bytes_to_read = min(desired_count, _MAX_READ_SIZE)
149
return self._read_bytes(bytes_to_read)
151
def _read_bytes(self, count):
152
raise NotImplementedError(self._read_bytes)
155
"""Read bytes from this request's response until a newline byte.
157
This isn't particularly efficient, so should only be used when the
158
expected size of the line is quite short.
160
:returns: a string of bytes ending in a newline (byte 0x0A).
162
line, excess = _get_line(self.read_bytes)
163
self._push_back(excess)
166
def _report_activity(self, bytes, direction):
167
"""Notify that this medium has activity.
169
Implementations should call this from all methods that actually do IO.
170
Be careful that it's not called twice, if one method is implemented on
173
:param bytes: Number of bytes read or written.
174
:param direction: 'read' or 'write' or None.
176
ui.ui_factory.report_transport_activity(self, bytes, direction)
179
class SmartServerStreamMedium(SmartMedium):
180
"""Handles smart commands coming over a stream.
182
The stream may be a pipe connected to sshd, or a tcp socket, or an
183
in-process fifo for testing.
185
One instance is created for each connected client; it can serve multiple
186
requests in the lifetime of the connection.
188
The server passes requests through to an underlying backing transport,
189
which will typically be a LocalTransport looking at the server's filesystem.
191
:ivar _push_back_buffer: a str of bytes that have been read from the stream
192
but not used yet, or None if there are no buffered bytes. Subclasses
193
should make sure to exhaust this buffer before reading more bytes from
194
the stream. See also the _push_back method.
197
def __init__(self, backing_transport, root_client_path='/'):
198
"""Construct new server.
200
:param backing_transport: Transport for the directory served.
202
# backing_transport could be passed to serve instead of __init__
203
self.backing_transport = backing_transport
204
self.root_client_path = root_client_path
205
self.finished = False
206
SmartMedium.__init__(self)
209
"""Serve requests until the client disconnects."""
210
# Keep a reference to stderr because the sys module's globals get set to
211
# None during interpreter shutdown.
212
from sys import stderr
214
while not self.finished:
215
server_protocol = self._build_protocol()
216
self._serve_one_request(server_protocol)
218
stderr.write("%s terminating on exception %s\n" % (self, e))
221
def _build_protocol(self):
222
"""Identifies the version of the incoming request, and returns an
223
a protocol object that can interpret it.
225
If more bytes than the version prefix of the request are read, they will
226
be fed into the protocol before it is returned.
228
:returns: a SmartServerRequestProtocol.
230
bytes = self._get_line()
231
protocol_factory, unused_bytes = _get_protocol_factory_for_bytes(bytes)
232
protocol = protocol_factory(
233
self.backing_transport, self._write_out, self.root_client_path)
234
protocol.accept_bytes(unused_bytes)
237
def _serve_one_request(self, protocol):
238
"""Read one request from input, process, send back a response.
240
:param protocol: a SmartServerRequestProtocol.
243
self._serve_one_request_unguarded(protocol)
244
except KeyboardInterrupt:
247
self.terminate_due_to_error()
249
def terminate_due_to_error(self):
250
"""Called when an unhandled exception from the protocol occurs."""
251
raise NotImplementedError(self.terminate_due_to_error)
253
def _read_bytes(self, desired_count):
254
"""Get some bytes from the medium.
256
:param desired_count: number of bytes we want to read.
258
raise NotImplementedError(self._read_bytes)
261
class SmartServerSocketStreamMedium(SmartServerStreamMedium):
263
def __init__(self, sock, backing_transport, root_client_path='/'):
266
:param sock: the socket the server will read from. It will be put
269
SmartServerStreamMedium.__init__(
270
self, backing_transport, root_client_path=root_client_path)
271
sock.setblocking(True)
274
def _serve_one_request_unguarded(self, protocol):
275
while protocol.next_read_size():
276
# We can safely try to read large chunks. If there is less data
277
# than MAX_SOCKET_CHUNK ready, the socket will just return a
278
# short read immediately rather than block.
279
bytes = self.read_bytes(osutils.MAX_SOCKET_CHUNK)
283
protocol.accept_bytes(bytes)
285
self._push_back(protocol.unused_data)
287
def _read_bytes(self, desired_count):
288
return osutils.read_bytes_from_socket(
289
self.socket, self._report_activity)
291
def terminate_due_to_error(self):
292
# TODO: This should log to a server log file, but no such thing
293
# exists yet. Andrew Bennetts 2006-09-29.
297
def _write_out(self, bytes):
298
tstart = osutils.timer_func()
299
osutils.send_all(self.socket, bytes, self._report_activity)
300
if 'hpss' in debug.debug_flags:
301
thread_id = thread.get_ident()
302
trace.mutter('%12s: [%s] %d bytes to the socket in %.3fs'
303
% ('wrote', thread_id, len(bytes),
304
osutils.timer_func() - tstart))
307
class SmartServerPipeStreamMedium(SmartServerStreamMedium):
309
def __init__(self, in_file, out_file, backing_transport):
310
"""Construct new server.
312
:param in_file: Python file from which requests can be read.
313
:param out_file: Python file to write responses.
314
:param backing_transport: Transport for the directory served.
316
SmartServerStreamMedium.__init__(self, backing_transport)
317
if sys.platform == 'win32':
318
# force binary mode for files
320
for f in (in_file, out_file):
321
fileno = getattr(f, 'fileno', None)
323
msvcrt.setmode(fileno(), os.O_BINARY)
327
def _serve_one_request_unguarded(self, protocol):
329
# We need to be careful not to read past the end of the current
330
# request, or else the read from the pipe will block, so we use
331
# protocol.next_read_size().
332
bytes_to_read = protocol.next_read_size()
333
if bytes_to_read == 0:
334
# Finished serving this request.
337
bytes = self.read_bytes(bytes_to_read)
339
# Connection has been closed.
343
protocol.accept_bytes(bytes)
345
def _read_bytes(self, desired_count):
346
return self._in.read(desired_count)
348
def terminate_due_to_error(self):
349
# TODO: This should log to a server log file, but no such thing
350
# exists yet. Andrew Bennetts 2006-09-29.
354
def _write_out(self, bytes):
355
self._out.write(bytes)
30
from bzrlib import errors
31
from bzrlib.smart.protocol import SmartServerRequestProtocolOne
34
from bzrlib.transport import ssh
35
except errors.ParamikoNotPresent:
36
# no paramiko. SmartSSHClientMedium will break.
358
40
class SmartClientMediumRequest(object):
462
144
return self._read_bytes(count)
464
146
def _read_bytes(self, count):
465
"""Helper for SmartClientMediumRequest.read_bytes.
147
"""Helper for read_bytes.
467
149
read_bytes checks the state of the request to determing if bytes
468
150
should be read. After that it hands off to _read_bytes to do the
471
By default this forwards to self._medium.read_bytes because we are
472
operating on the medium's stream.
474
return self._medium.read_bytes(count)
477
line = self._read_line()
478
if not line.endswith('\n'):
479
# end of file encountered reading from server
480
raise errors.ConnectionReset(
481
"Unexpected end of message. Please check connectivity "
482
"and permissions, and report a bug if problems persist.")
485
def _read_line(self):
486
"""Helper for SmartClientMediumRequest.read_line.
488
By default this forwards to self._medium._get_line because we are
489
operating on the medium's stream.
491
return self._medium._get_line()
494
class _DebugCounter(object):
495
"""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
153
raise NotImplementedError(self._read_bytes)
156
class SmartClientStreamMediumRequest(SmartClientMediumRequest):
157
"""A SmartClientMediumRequest that works with an SmartClientStreamMedium."""
159
def __init__(self, medium):
160
SmartClientMediumRequest.__init__(self, medium)
161
# check that we are safe concurrency wise. If some streams start
162
# allowing concurrent requests - i.e. via multiplexing - then this
163
# assert should be moved to SmartClientStreamMedium.get_request,
164
# and the setting/unsetting of _current_request likewise moved into
165
# that class : but its unneeded overhead for now. RBC 20060922
166
if self._medium._current_request is not None:
167
raise errors.TooManyConcurrentRequests(self._medium)
168
self._medium._current_request = self
170
def _accept_bytes(self, bytes):
171
"""See SmartClientMediumRequest._accept_bytes.
173
This forwards to self._medium._accept_bytes because we are operating
174
on the mediums stream.
176
self._medium._accept_bytes(bytes)
178
def _finished_reading(self):
179
"""See SmartClientMediumRequest._finished_reading.
181
This clears the _current_request on self._medium to allow a new
182
request to be created.
184
assert self._medium._current_request is self
185
self._medium._current_request = None
187
def _finished_writing(self):
188
"""See SmartClientMediumRequest._finished_writing.
190
This invokes self._medium._flush to ensure all bytes are transmitted.
192
self._medium._flush()
194
def _read_bytes(self, count):
195
"""See SmartClientMediumRequest._read_bytes.
197
This forwards to self._medium._read_bytes because we are operating
198
on the mediums stream.
200
return self._medium._read_bytes(count)
203
class SmartServerStreamMedium(object):
204
"""Handles smart commands coming over a stream.
206
The stream may be a pipe connected to sshd, or a tcp socket, or an
207
in-process fifo for testing.
209
One instance is created for each connected client; it can serve multiple
210
requests in the lifetime of the connection.
212
The server passes requests through to an underlying backing transport,
213
which will typically be a LocalTransport looking at the server's filesystem.
503
self.counts = weakref.WeakKeyDictionary()
504
client._SmartClient.hooks.install_named_hook(
505
'call', self.increment_call_count, 'hpss call counter')
506
atexit.register(self.flush_all)
508
def track(self, medium):
509
"""Start tracking calls made to a medium.
511
This only keeps a weakref to the medium, so shouldn't affect the
514
medium_repr = repr(medium)
515
# Add this medium to the WeakKeyDictionary
516
self.counts[medium] = dict(count=0, vfs_count=0,
517
medium_repr=medium_repr)
518
# Weakref callbacks are fired in reverse order of their association
519
# with the referenced object. So we add a weakref *after* adding to
520
# the WeakKeyDict so that we can report the value from it before the
521
# entry is removed by the WeakKeyDict's own callback.
522
ref = weakref.ref(medium, self.done)
524
def increment_call_count(self, params):
525
# Increment the count in the WeakKeyDictionary
526
value = self.counts[params.medium]
529
request_method = request.request_handlers.get(params.method)
531
# A method we don't know about doesn't count as a VFS method.
533
if issubclass(request_method, vfs.VfsRequest):
534
value['vfs_count'] += 1
537
value = self.counts[ref]
538
count, vfs_count, medium_repr = (
539
value['count'], value['vfs_count'], value['medium_repr'])
540
# In case this callback is invoked for the same ref twice (by the
541
# weakref callback and by the atexit function), set the call count back
542
# to 0 so this item won't be reported twice.
544
value['vfs_count'] = 0
546
trace.note('HPSS calls: %d (%d vfs) %s',
547
count, vfs_count, medium_repr)
550
for ref in list(self.counts.keys()):
553
_debug_counter = None
556
class SmartClientMedium(SmartMedium):
216
def __init__(self, backing_transport):
217
"""Construct new server.
219
:param backing_transport: Transport for the directory served.
221
# backing_transport could be passed to serve instead of __init__
222
self.backing_transport = backing_transport
223
self.finished = False
226
"""Serve requests until the client disconnects."""
227
# Keep a reference to stderr because the sys module's globals get set to
228
# None during interpreter shutdown.
229
from sys import stderr
231
while not self.finished:
232
protocol = SmartServerRequestProtocolOne(self.backing_transport,
234
self._serve_one_request(protocol)
236
stderr.write("%s terminating on exception %s\n" % (self, e))
239
def _serve_one_request(self, protocol):
240
"""Read one request from input, process, send back a response.
242
:param protocol: a SmartServerRequestProtocol.
245
self._serve_one_request_unguarded(protocol)
246
except KeyboardInterrupt:
249
self.terminate_due_to_error()
251
def terminate_due_to_error(self):
252
"""Called when an unhandled exception from the protocol occurs."""
253
raise NotImplementedError(self.terminate_due_to_error)
256
class SmartServerSocketStreamMedium(SmartServerStreamMedium):
258
def __init__(self, sock, backing_transport):
261
:param sock: the socket the server will read from. It will be put
264
SmartServerStreamMedium.__init__(self, backing_transport)
266
sock.setblocking(True)
269
def _serve_one_request_unguarded(self, protocol):
270
while protocol.next_read_size():
272
protocol.accept_bytes(self.push_back)
275
bytes = self.socket.recv(4096)
279
protocol.accept_bytes(bytes)
281
self.push_back = protocol.excess_buffer
283
def terminate_due_to_error(self):
284
"""Called when an unhandled exception from the protocol occurs."""
285
# TODO: This should log to a server log file, but no such thing
286
# exists yet. Andrew Bennetts 2006-09-29.
290
def _write_out(self, bytes):
291
self.socket.sendall(bytes)
294
class SmartServerPipeStreamMedium(SmartServerStreamMedium):
296
def __init__(self, in_file, out_file, backing_transport):
297
"""Construct new server.
299
:param in_file: Python file from which requests can be read.
300
:param out_file: Python file to write responses.
301
:param backing_transport: Transport for the directory served.
303
SmartServerStreamMedium.__init__(self, backing_transport)
304
if sys.platform == 'win32':
305
# force binary mode for files
307
for f in (in_file, out_file):
308
fileno = getattr(f, 'fileno', None)
310
msvcrt.setmode(fileno(), os.O_BINARY)
314
def _serve_one_request_unguarded(self, protocol):
316
bytes_to_read = protocol.next_read_size()
317
if bytes_to_read == 0:
318
# Finished serving this request.
321
bytes = self._in.read(bytes_to_read)
323
# Connection has been closed.
327
protocol.accept_bytes(bytes)
329
def terminate_due_to_error(self):
330
# TODO: This should log to a server log file, but no such thing
331
# exists yet. Andrew Bennetts 2006-09-29.
335
def _write_out(self, bytes):
336
self._out.write(bytes)
339
class SmartClientMedium(object):
557
340
"""Smart client is a medium for sending smart protocol requests over."""
559
def __init__(self, base):
560
super(SmartClientMedium, self).__init__()
562
self._protocol_version_error = None
563
self._protocol_version = None
564
self._done_hello = False
565
# Be optimistic: we assume the remote end can accept new remote
566
# requests until we get an error saying otherwise.
567
# _remote_version_is_before tracks the bzr version the remote side
568
# can be based on what we've seen so far.
569
self._remote_version_is_before = None
570
# Install debug hook function if debug flag is set.
571
if 'hpss' in debug.debug_flags:
572
global _debug_counter
573
if _debug_counter is None:
574
_debug_counter = _DebugCounter()
575
_debug_counter.track(self)
577
def _is_remote_before(self, version_tuple):
578
"""Is it possible the remote side supports RPCs for a given version?
582
needed_version = (1, 2)
583
if medium._is_remote_before(needed_version):
584
fallback_to_pre_1_2_rpc()
588
except UnknownSmartMethod:
589
medium._remember_remote_is_before(needed_version)
590
fallback_to_pre_1_2_rpc()
592
:seealso: _remember_remote_is_before
594
if self._remote_version_is_before is None:
595
# So far, the remote side seems to support everything
597
return version_tuple >= self._remote_version_is_before
599
def _remember_remote_is_before(self, version_tuple):
600
"""Tell this medium that the remote side is older the given version.
602
:seealso: _is_remote_before
604
if (self._remote_version_is_before is not None and
605
version_tuple > self._remote_version_is_before):
606
# We have been told that the remote side is older than some version
607
# which is newer than a previously supplied older-than version.
608
# This indicates that some smart verb call is not guarded
609
# appropriately (it should simply not have been tried).
611
"_remember_remote_is_before(%r) called, but "
612
"_remember_remote_is_before(%r) was called previously."
613
, version_tuple, self._remote_version_is_before)
614
if 'hpss' in debug.debug_flags:
615
ui.ui_factory.show_warning(
616
"_remember_remote_is_before(%r) called, but "
617
"_remember_remote_is_before(%r) was called previously."
618
% (version_tuple, self._remote_version_is_before))
620
self._remote_version_is_before = version_tuple
622
def protocol_version(self):
623
"""Find out if 'hello' smart request works."""
624
if self._protocol_version_error is not None:
625
raise self._protocol_version_error
626
if not self._done_hello:
628
medium_request = self.get_request()
629
# Send a 'hello' request in protocol version one, for maximum
630
# backwards compatibility.
631
client_protocol = protocol.SmartClientRequestProtocolOne(medium_request)
632
client_protocol.query_version()
633
self._done_hello = True
634
except errors.SmartProtocolError, e:
635
# Cache the error, just like we would cache a successful
637
self._protocol_version_error = e
641
def should_probe(self):
642
"""Should RemoteBzrDirFormat.probe_transport send a smart request on
645
Some transports are unambiguously smart-only; there's no need to check
646
if the transport is able to carry smart requests, because that's all
647
it is for. In those cases, this method should return False.
649
But some HTTP transports can sometimes fail to carry smart requests,
650
but still be usuable for accessing remote bzrdirs via plain file
651
accesses. So for those transports, their media should return True here
652
so that RemoteBzrDirFormat can determine if it is appropriate for that
657
342
def disconnect(self):
658
343
"""If this medium maintains a persistent connection, close it.
660
345
The default implementation does nothing.
663
def remote_path_from_transport(self, transport):
664
"""Convert transport into a path suitable for using in a request.
666
Note that the resulting remote path doesn't encode the host name or
667
anything but path, so it is only safe to use it in requests sent over
668
the medium from the matching transport.
670
medium_base = urlutils.join(self.base, '/')
671
rel_url = urlutils.relative_url(medium_base, transport.base)
672
return urllib.unquote(rel_url)
675
349
class SmartClientStreamMedium(SmartClientMedium):
676
350
"""Stream based medium common class.
added
removed
bzrlib/smart/medium.py
