31
from bzrlib.lazy_import import lazy_import
32
lazy_import(globals(), """
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31
from bzrlib import (
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from bzrlib.smart import client, protocol, request, vfs
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from bzrlib.smart.protocol import (
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SmartClientRequestProtocolOne,
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SmartServerRequestProtocolOne,
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SmartServerRequestProtocolTwo,
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from bzrlib.transport import ssh
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from bzrlib import osutils
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# Throughout this module buffer size parameters are either limited to be at
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# most _MAX_READ_SIZE, or are ignored and _MAX_READ_SIZE is used instead.
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# For this module's purposes, MAX_SOCKET_CHUNK is a reasonable size for reads
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# from non-sockets as well.
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_MAX_READ_SIZE = osutils.MAX_SOCKET_CHUNK
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def _get_protocol_factory_for_bytes(bytes):
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"""Determine the right protocol factory for 'bytes'.
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This will return an appropriate protocol factory depending on the version
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of the protocol being used, as determined by inspecting the given bytes.
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The bytes should have at least one newline byte (i.e. be a whole line),
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otherwise it's possible that a request will be incorrectly identified as
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Typical use would be::
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factory, unused_bytes = _get_protocol_factory_for_bytes(bytes)
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server_protocol = factory(transport, write_func, root_client_path)
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server_protocol.accept_bytes(unused_bytes)
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:param bytes: a str of bytes of the start of the request.
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:returns: 2-tuple of (protocol_factory, unused_bytes). protocol_factory is
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a callable that takes three args: transport, write_func,
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root_client_path. unused_bytes are any bytes that were not part of a
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protocol version marker.
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if bytes.startswith(protocol.MESSAGE_VERSION_THREE):
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protocol_factory = protocol.build_server_protocol_three
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bytes = bytes[len(protocol.MESSAGE_VERSION_THREE):]
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elif bytes.startswith(protocol.REQUEST_VERSION_TWO):
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protocol_factory = protocol.SmartServerRequestProtocolTwo
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bytes = bytes[len(protocol.REQUEST_VERSION_TWO):]
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protocol_factory = protocol.SmartServerRequestProtocolOne
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return protocol_factory, bytes
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def _get_line(read_bytes_func):
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"""Read bytes using read_bytes_func until a newline byte.
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This isn't particularly efficient, so should only be used when the
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expected size of the line is quite short.
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:returns: a tuple of two strs: (line, excess)
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while newline_pos == -1:
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new_bytes = read_bytes_func(1)
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# Ran out of bytes before receiving a complete line.
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newline_pos = bytes.find('\n')
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line = bytes[:newline_pos+1]
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excess = bytes[newline_pos+1:]
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class SmartMedium(object):
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"""Base class for smart protocol media, both client- and server-side."""
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self._push_back_buffer = None
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def _push_back(self, bytes):
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"""Return unused bytes to the medium, because they belong to the next
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This sets the _push_back_buffer to the given bytes.
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if self._push_back_buffer is not None:
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raise AssertionError(
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"_push_back called when self._push_back_buffer is %r"
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% (self._push_back_buffer,))
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self._push_back_buffer = bytes
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def _get_push_back_buffer(self):
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if self._push_back_buffer == '':
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raise AssertionError(
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'%s._push_back_buffer should never be the empty string, '
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'which can be confused with EOF' % (self,))
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bytes = self._push_back_buffer
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self._push_back_buffer = None
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def read_bytes(self, desired_count):
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"""Read some bytes from this medium.
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:returns: some bytes, possibly more or less than the number requested
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in 'desired_count' depending on the medium.
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if self._push_back_buffer is not None:
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return self._get_push_back_buffer()
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bytes_to_read = min(desired_count, _MAX_READ_SIZE)
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return self._read_bytes(bytes_to_read)
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def _read_bytes(self, count):
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raise NotImplementedError(self._read_bytes)
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"""Read bytes from this request's response until a newline byte.
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This isn't particularly efficient, so should only be used when the
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expected size of the line is quite short.
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:returns: a string of bytes ending in a newline (byte 0x0A).
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line, excess = _get_line(self.read_bytes)
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self._push_back(excess)
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def _report_activity(self, bytes, direction):
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"""Notify that this medium has activity.
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Implementations should call this from all methods that actually do IO.
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Be careful that it's not called twice, if one method is implemented on
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:param bytes: Number of bytes read or written.
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:param direction: 'read' or 'write' or None.
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ui.ui_factory.report_transport_activity(self, bytes, direction)
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class SmartServerStreamMedium(SmartMedium):
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class SmartServerStreamMedium(object):
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"""Handles smart commands coming over a stream.
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The stream may be a pipe connected to sshd, or a tcp socket, or an
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SmartServerStreamMedium.__init__(
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self, backing_transport, root_client_path=root_client_path)
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sock.setblocking(True)
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self.socket = sock
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def _serve_one_request_unguarded(self, protocol):
275
159
while protocol.next_read_size():
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# We can safely try to read large chunks. If there is less data
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# than MAX_SOCKET_CHUNK ready, the socket will just return a
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# short read immediately rather than block.
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bytes = self.read_bytes(osutils.MAX_SOCKET_CHUNK)
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protocol.accept_bytes(bytes)
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self._push_back(protocol.unused_data)
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def _read_bytes(self, desired_count):
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return osutils.read_bytes_from_socket(
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self.socket, self._report_activity)
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protocol.accept_bytes(self.push_back)
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bytes = self._get_bytes(4096)
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protocol.accept_bytes(bytes)
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self.push_back = protocol.excess_buffer
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def _get_bytes(self, desired_count):
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# We ignore the desired_count because on sockets it's more efficient to
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return self.socket.recv(4096)
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def terminate_due_to_error(self):
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"""Called when an unhandled exception from the protocol occurs."""
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# TODO: This should log to a server log file, but no such thing
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# exists yet. Andrew Bennetts 2006-09-29.
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self.socket.close()
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self.finished = True
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def _write_out(self, bytes):
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tstart = osutils.timer_func()
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osutils.send_all(self.socket, bytes, self._report_activity)
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if 'hpss' in debug.debug_flags:
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thread_id = thread.get_ident()
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trace.mutter('%12s: [%s] %d bytes to the socket in %.3fs'
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% ('wrote', thread_id, len(bytes),
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osutils.timer_func() - tstart))
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osutils.send_all(self.socket, bytes)
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class SmartServerPipeStreamMedium(SmartServerStreamMedium):
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return self._read_bytes(count)
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def _read_bytes(self, count):
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"""Helper for SmartClientMediumRequest.read_bytes.
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"""Helper for read_bytes.
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read_bytes checks the state of the request to determing if bytes
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should be read. After that it hands off to _read_bytes to do the
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By default this forwards to self._medium.read_bytes because we are
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operating on the medium's stream.
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return self._medium.read_bytes(count)
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raise NotImplementedError(self._read_bytes)
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def read_line(self):
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line = self._read_line()
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if not line.endswith('\n'):
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# end of file encountered reading from server
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raise errors.ConnectionReset(
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"Unexpected end of message. Please check connectivity "
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"and permissions, and report a bug if problems persist.")
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"""Read bytes from this request's response until a newline byte.
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This isn't particularly efficient, so should only be used when the
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expected size of the line is quite short.
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:returns: a string of bytes ending in a newline (byte 0x0A).
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# XXX: this duplicates SmartClientRequestProtocolOne._recv_tuple
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while not line or line[-1] != '\n':
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new_char = self.read_bytes(1)
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# end of file encountered reading from server
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raise errors.ConnectionReset(
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"please check connectivity and permissions",
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"(and try -Dhpss if further diagnosis is required)")
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def _read_line(self):
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"""Helper for SmartClientMediumRequest.read_line.
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By default this forwards to self._medium._get_line because we are
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operating on the medium's stream.
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return self._medium._get_line()
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class _DebugCounter(object):
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"""An object that counts the HPSS calls made to each client medium.
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When a medium is garbage-collected, or failing that when atexit functions
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are run, the total number of calls made on that medium are reported via
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self.counts = weakref.WeakKeyDictionary()
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client._SmartClient.hooks.install_named_hook(
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'call', self.increment_call_count, 'hpss call counter')
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atexit.register(self.flush_all)
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def track(self, medium):
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"""Start tracking calls made to a medium.
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This only keeps a weakref to the medium, so shouldn't affect the
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medium_repr = repr(medium)
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# Add this medium to the WeakKeyDictionary
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self.counts[medium] = dict(count=0, vfs_count=0,
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medium_repr=medium_repr)
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# Weakref callbacks are fired in reverse order of their association
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# with the referenced object. So we add a weakref *after* adding to
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# the WeakKeyDict so that we can report the value from it before the
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# entry is removed by the WeakKeyDict's own callback.
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ref = weakref.ref(medium, self.done)
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def increment_call_count(self, params):
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# Increment the count in the WeakKeyDictionary
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value = self.counts[params.medium]
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request_method = request.request_handlers.get(params.method)
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# A method we don't know about doesn't count as a VFS method.
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if issubclass(request_method, vfs.VfsRequest):
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value['vfs_count'] += 1
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value = self.counts[ref]
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count, vfs_count, medium_repr = (
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value['count'], value['vfs_count'], value['medium_repr'])
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# In case this callback is invoked for the same ref twice (by the
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# weakref callback and by the atexit function), set the call count back
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# to 0 so this item won't be reported twice.
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value['vfs_count'] = 0
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trace.note('HPSS calls: %d (%d vfs) %s',
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count, vfs_count, medium_repr)
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for ref in list(self.counts.keys()):
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_debug_counter = None
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class SmartClientMedium(SmartMedium):
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class SmartClientMedium(object):
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"""Smart client is a medium for sending smart protocol requests over."""
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def __init__(self, base):
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super(SmartClientMedium, self).__init__()
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self._protocol_version_error = None
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self._protocol_version = None
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self._done_hello = False
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# Be optimistic: we assume the remote end can accept new remote
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# requests until we get an error saying otherwise.
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# _remote_version_is_before tracks the bzr version the remote side
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# can be based on what we've seen so far.
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self._remote_version_is_before = None
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# Install debug hook function if debug flag is set.
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if 'hpss' in debug.debug_flags:
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global _debug_counter
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if _debug_counter is None:
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_debug_counter = _DebugCounter()
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_debug_counter.track(self)
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def _is_remote_before(self, version_tuple):
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"""Is it possible the remote side supports RPCs for a given version?
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needed_version = (1, 2)
583
if medium._is_remote_before(needed_version):
584
fallback_to_pre_1_2_rpc()
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except UnknownSmartMethod:
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medium._remember_remote_is_before(needed_version)
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fallback_to_pre_1_2_rpc()
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:seealso: _remember_remote_is_before
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if self._remote_version_is_before is None:
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# So far, the remote side seems to support everything
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return version_tuple >= self._remote_version_is_before
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def _remember_remote_is_before(self, version_tuple):
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"""Tell this medium that the remote side is older the given version.
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:seealso: _is_remote_before
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if (self._remote_version_is_before is not None and
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version_tuple > self._remote_version_is_before):
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# We have been told that the remote side is older than some version
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# which is newer than a previously supplied older-than version.
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# This indicates that some smart verb call is not guarded
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# appropriately (it should simply not have been tried).
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"_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:
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ui.ui_factory.show_warning(
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"_remember_remote_is_before(%r) called, but "
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"_remember_remote_is_before(%r) was called previously."
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% (version_tuple, self._remote_version_is_before))
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self._remote_version_is_before = version_tuple
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def protocol_version(self):
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"""Find out if 'hello' smart request works."""
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"""Find out the best protocol version to use."""
624
382
if self._protocol_version_error is not None:
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raise self._protocol_version_error
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if not self._done_hello:
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if self._protocol_version is None:
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386
medium_request = self.get_request()
629
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# Send a 'hello' request in protocol version one, for maximum
630
388
# backwards compatibility.
631
client_protocol = protocol.SmartClientRequestProtocolOne(medium_request)
632
client_protocol.query_version()
633
self._done_hello = True
389
client_protocol = SmartClientRequestProtocolOne(medium_request)
390
self._protocol_version = client_protocol.query_version()
634
391
except errors.SmartProtocolError, e:
635
392
# Cache the error, just like we would cache a successful
637
394
self._protocol_version_error = e
641
def should_probe(self):
642
"""Should RemoteBzrDirFormat.probe_transport send a smart request on
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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
396
return self._protocol_version
657
398
def disconnect(self):
658
399
"""If this medium maintains a persistent connection, close it.
660
401
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
405
class SmartClientStreamMedium(SmartClientMedium):
676
406
"""Stream based medium common class.
738
470
def _read_bytes(self, count):
739
471
"""See SmartClientStreamMedium._read_bytes."""
740
bytes = osutils.until_no_eintr(self._readable_pipe.read, count)
741
self._report_activity(len(bytes), 'read')
472
return self._readable_pipe.read(count)
745
475
class SmartSSHClientMedium(SmartClientStreamMedium):
746
476
"""A client medium using SSH."""
748
478
def __init__(self, host, port=None, username=None, password=None,
749
base=None, vendor=None, bzr_remote_path=None):
479
vendor=None, bzr_remote_path=None):
750
480
"""Creates a client that will connect on the first use.
752
482
:param vendor: An optional override for the ssh vendor to use. See
753
483
bzrlib.transport.ssh for details on ssh vendors.
485
SmartClientStreamMedium.__init__(self)
755
486
self._connected = False
756
487
self._host = host
757
488
self._password = password
758
489
self._port = port
759
490
self._username = username
760
# for the benefit of progress making a short description of this
762
self._scheme = 'bzr+ssh'
763
# SmartClientStreamMedium stores the repr of this object in its
764
# _DebugCounter so we have to store all the values used in our repr
765
# method before calling the super init.
766
SmartClientStreamMedium.__init__(self, base)
767
491
self._read_from = None
768
492
self._ssh_connection = None
769
493
self._vendor = vendor
770
494
self._write_to = None
771
495
self._bzr_remote_path = bzr_remote_path
774
if self._port is None:
777
maybe_port = ':%s' % self._port
778
return "%s(%s://%s@%s%s/)" % (
779
self.__class__.__name__,
496
if self._bzr_remote_path is None:
497
symbol_versioning.warn(
498
'bzr_remote_path is required as of bzr 0.92',
499
DeprecationWarning, stacklevel=2)
500
self._bzr_remote_path = os.environ.get('BZR_REMOTE_PATH', 'bzr')
785
502
def _accept_bytes(self, bytes):
786
503
"""See SmartClientStreamMedium.accept_bytes."""
787
504
self._ensure_connection()
788
505
self._write_to.write(bytes)
789
self._report_activity(len(bytes), 'write')
791
507
def disconnect(self):
792
508
"""See SmartClientMedium.disconnect()."""
added
removed
bzrlib/smart/medium.py
