def test_write_when_write_event_and_not_pending(self):
sock = EventSocket()
sock._write_event = mock()
expect( sock._write_event.pending ).returns( False )
expect( sock._write_event.add )
expect( sock._flag_activity )
sock.write( 'foo' )
assert_equals( deque(['foo']), sock._write_buf )
def test_write_when_write_event_is_pending_and_debugging(self):
sock = EventSocket()
sock._write_event = mock()
sock._peername = 'peername'
sock._write_buf = deque(['data'])
sock._debug = 2
sock._logger = mock()
expect( sock._write_event.pending ).returns( True )
expect( sock._logger.debug ).args(str, 3, 7, 'peername')
expect( sock._flag_activity )
sock.write( 'foo' )
assert_equals( deque(['data', 'foo']), sock._write_buf )
class Connection(object):
class TooManyChannels(ConnectionError): '''This connection has too many channels open. Non-fatal.'''
class InvalidChannel(ConnectionError): '''The channel id does not correspond to an existing channel. Non-fatal.'''
def __init__(self, **kwargs):
'''
Initialize the connection.
'''
self._debug = kwargs.get('debug', False)
self._logger = kwargs.get('logger', root_logger)
self._user = kwargs.get('user', 'guest')
self._password = kwargs.get('password', 'guest')
self._host = kwargs.get('host', 'localhost')
self._vhost = kwargs.get('vhost', '/')
self._connect_timeout = kwargs.get('connect_timeout', 5)
self._sock_opts = kwargs.get('sock_opts')
self._sock = None
self._heartbeat = kwargs.get('heartbeat')
self._reconnect_cb = kwargs.get('reconnect_cb')
self._close_cb = kwargs.get('close_cb')
self._login_method = kwargs.get('login_method', 'AMQPLAIN')
self._locale = kwargs.get('locale', 'en_US')
self._client_properties = kwargs.get('client_properties')
self._properties = LIBRARY_PROPERTIES.copy()
if self._client_properties:
self._properties.update( self._client_properties )
self._closed = False
self._connected = False
self._close_info = {
'reply_code' : 0,
'reply_text' : 'first connect',
'class_id' : 0,
'method_id' : 0
}
self._channels = {
0 : ConnectionChannel(self, 0)
}
login_response = Writer()
login_response.write_table({'LOGIN': self._user, 'PASSWORD': self._password})
#stream = BytesIO()
#login_response.flush(stream)
#self._login_response = stream.getvalue()[4:] #Skip the length
#at the beginning
self._login_response = login_response.buffer()[4:]
self._channel_counter = 0
self._channel_max = 65535
self._frame_max = 65535
self._frames_read = 0
self._frames_written = 0
self._strategy = kwargs.get('connection_strategy')
if not self._strategy:
self._strategy = ConnectionStrategy( self, self._host, reconnect_cb = self._reconnect_cb )
self._strategy.connect()
self._output_frame_buffer = []
@property
def logger(self):
return self._logger
@property
def debug(self):
return self._debug
@property
def frame_max(self):
return self._frame_max
@property
def channel_max(self):
return self._channel_max
@property
def frames_read(self):
'''Number of frames read in the lifetime of this connection.'''
return self._frames_read
@property
def frames_written(self):
'''Number of frames written in the lifetime of this connection.'''
return self._frames_written
@property
def close_info(self):
'''Return dict with information on why this connection is closed. Will
return None if the connections is open.'''
return self._close_info if self._closed else None
def reconnect(self):
'''Reconnect to the configured host and port.'''
self._strategy.connect()
def connect(self, host, port):
'''
Connect to a host and port. Can be called directly, or is called by the
strategy as it tries to find and connect to hosts.
'''
# Clear the connect state immediately since we're no longer connected
# at this point.
self._connected = False
# NOTE: purposefully leave output_frame_buffer alone so that pending writes can
# still occur. this allows the reconnect to occur silently without
# completely breaking any pending data on, say, a channel that was just
# opened.
self._sock = EventSocket( read_cb=self._sock_read_cb,
close_cb=self._sock_close_cb, error_cb=self._sock_error_cb,
debug=self._debug, logger=self._logger )
self._sock.settimeout( self._connect_timeout )
if self._sock_opts:
for k,v in self._sock_opts.iteritems():
family,type = k
self._sock.setsockopt(family, type, v)
self._sock.connect( (host,port) )
self._sock.setblocking( False )
# Only after the socket has connected do we clear this state; closed must
# be False so that writes can be buffered in writePacket(). The closed
# state might have been set to True due to a socket error or a redirect.
self._host = "%s:%d"%(host,port)
self._closed = False
self._close_info = {
'reply_code' : 0,
'reply_text' : 'failed to connect to %s'%(self._host),
'class_id' : 0,
'method_id' : 0
}
self._sock.write( PROTOCOL_HEADER )
def disconnect(self):
'''
Disconnect from the current host, but otherwise leave this object "open"
so that it can be reconnected.
'''
self._connected = False
if self._sock!=None:
self._sock.close_cb = None
try:
self._sock.close()
except:
self.logger.error("Failed to disconnect socket to %s", self._host, exc_info=True)
self._sock = None
def add_reconnect_callback(self, callback):
'''Adds a reconnect callback to the strategy. This can be used to
resubscribe to exchanges, etc.'''
self._strategy.reconnect_callbacks.append(callback)
###
### EventSocket callbacks
###
def _sock_read_cb(self, sock):
'''
Callback when there's data to read on the socket.
'''
try:
self._read_frames()
except:
self.logger.error("Failed to read frames from %s", self._host, exc_info=True)
self.close( reply_code=501, reply_text='Error parsing frames' )
def _sock_close_cb(self, sock):
"""
Callback when socket closed. This is intended to be the callback when the
closure is unexpected.
"""
self.logger.warning( 'socket to %s closed unexpectedly', self._host )
self._close_info = {
'reply_code' : 0,
'reply_text' : 'socket closed unexpectedly to %s'%(self._host),
'class_id' : 0,
'method_id' : 0
}
# We're not connected any more (we're not closed but we're definitely not
# connected)
self._connected = False
self._sock = None
# Call back to a user-provided close function
self._callback_close()
# Fail and do nothing. If you haven't configured permissions and that's
# why the socket is closing, this keeps us from looping.
self._strategy.fail()
def _sock_error_cb(self, sock, msg, exception=None):
"""
Callback when there's an error on the socket.
"""
self.logger.error( 'error on connection to %s: %s', self._host, msg)
self._close_info = {
'reply_code' : 0,
'reply_text' : 'socket error on host %s: %s'%(self._host, msg),
'class_id' : 0,
'method_id' : 0
}
# we're not connected any more (we're not closed but we're definitely not
# connected)
self._connected = False
self._sock = None
# Call back to a user-provided close function
self._callback_close()
# Fail and try to reconnect, because this is expected to be a transient error.
self._strategy.fail()
self._strategy.next_host()
###
### Connection methods
###
def _next_channel_id(self):
'''Return the next possible channel id. Is a circular enumeration.'''
self._channel_counter += 1
if self._channel_counter >= self._channel_max:
self._channel_counter = 1
return self._channel_counter
def channel(self, channel_id=None):
"""
Fetch a Channel object identified by the numeric channel_id, or
create that object if it doesn't already exist. If channel_id is not
None but no channel exists for that id, will raise InvalidChannel. If
there are already too many channels open, will raise TooManyChannels.
"""
if channel_id is None:
# adjust for channel 0
if len(self._channels)-1 >= self._channel_max:
raise Connection.TooManyChannels( "%d channels already open, max %d",
len(self._channels)-1, self._channel_max )
channel_id = self._next_channel_id()
while channel_id in self._channels:
channel_id = self._next_channel_id()
elif channel_id in self._channels:
return self._channels[channel_id]
else:
raise Connection.InvalidChannel("%s is not a valid channel id", channel_id )
# Call open() here so that ConnectionChannel doesn't have it called. Could
# also solve this other ways, but it's a HACK regardless.
rval = Channel(self, channel_id)
self._channels[ channel_id ] = rval
rval.open()
return rval
def close(self, reply_code=0, reply_text='', class_id=0, method_id=0):
'''
Close this connection.
'''
self._close_info = {
'reply_code' : reply_code,
'reply_text' : reply_text,
'class_id' : class_id,
'method_id' : method_id
}
self._channels[0].close()
def _close_socket(self):
'''Close the socket.'''
# The assumption here is that we don't want auto-reconnect to kick in if
# the socket is purposefully closed.
self._closed = True
# By the time we hear about the protocol-level closure, the socket may
# have already gone away.
if self._sock != None:
self._sock.close_cb = None
try:
self._sock.close()
except:
self.logger.error( 'error closing socket' )
self._sock = None
def _callback_close(self):
'''Callback to any close handler.'''
if self._close_cb:
try: self._close_cb()
except SystemExit: raise
except: self.logger.error( 'error calling close callback' )
def _read_frames(self):
'''
Read frames from the socket.
'''
# Because of the timer callback to dataRead when we re-buffered, there's a
# chance that in between we've lost the socket. If that's the case, just
# silently return as some code elsewhere would have already notified us.
# That bug could be fixed by improving the message reading so that we consume
# all possible messages and ensure that only a partial message was rebuffered,
# so that we can rely on the next read event to read the subsequent message.
if self._sock is None:
return
data = self._sock.read()
reader = Reader( data )
p_channels = set()
for frame in Frame.read_frames( reader ):
if self._debug > 1:
self.logger.debug( "READ: %s", frame )
self._frames_read += 1
ch = self.channel( frame.channel_id )
ch.buffer_frame( frame )
p_channels.add( ch )
# Still not clear on what's the best approach here. It seems there's a
# slight speedup by calling this directly rather than delaying, but the
# delay allows for pending IO with higher priority to execute.
self._process_channels( p_channels )
#event.timeout(0, self._process_channels, p_channels)
# HACK: read the buffer contents and re-buffer. Would prefer to pass
# buffer back, but there's no good way of asking the total size of the
# buffer, comparing to tell(), and then re-buffering. There's also no
# ability to clear the buffer up to the current position.
# NOTE: This will be cleared up once eventsocket supports the
# uber-awesome buffering scheme that will utilize mmap.
if reader.tell() < len(data):
self._sock.buffer( data[reader.tell():] )
def _process_channels(self, channels):
'''
Walk through a set of channels and process their frame buffer. Will
collect all socket output and flush in one write.
'''
for channel in channels:
channel.process_frames()
def _flush_buffered_frames(self):
# In the rare case (a bug) where this is called but send_frame thinks
# they should be buffered, don't clobber.
frames = self._output_frame_buffer
self._output_frame_buffer = []
for frame in frames:
self.send_frame( frame )
def send_frame(self, frame):
'''
Send a single frame. If there is an output buffer, write to that, else send
immediately to the socket.
'''
if self._closed:
if self._close_info and len(self._close_info['reply_text'])>0:
raise ConnectionClosed("connection is closed: %s : %s"%\
(self._close_info['reply_code'],self._close_info['reply_text']) )
raise ConnectionClosed("connection is closed")
if self._sock==None or (not self._connected and frame.channel_id!=0):
self._output_frame_buffer.append( frame )
return
if self._debug > 1:
self.logger.debug( "WRITE: %s", frame )
buf = bytearray()
frame.write_frame(buf)
self._sock.write( buf )
self._frames_written += 1
class Connection(object):
class TooManyChannels(ConnectionError):
'''This connection has too many channels open. Non-fatal.'''
class InvalidChannel(ConnectionError):
'''The channel id does not correspond to an existing channel. Non-fatal.'''
def __init__(self, **kwargs):
'''
Initialize the connection.
'''
self._debug = kwargs.get('debug', False)
self._logger = kwargs.get('logger', root_logger)
self._user = kwargs.get('user', 'guest')
self._password = kwargs.get('password', 'guest')
self._host = kwargs.get('host', 'localhost')
self._vhost = kwargs.get('vhost', '/')
self._connect_timeout = kwargs.get('connect_timeout', 5)
self._sock_opts = kwargs.get('sock_opts')
self._sock = None
self._heartbeat = kwargs.get('heartbeat')
self._reconnect_cb = kwargs.get('reconnect_cb')
self._close_cb = kwargs.get('close_cb')
self._login_method = kwargs.get('login_method', 'AMQPLAIN')
self._locale = kwargs.get('locale', 'en_US')
self._client_properties = kwargs.get('client_properties')
self._properties = LIBRARY_PROPERTIES.copy()
if self._client_properties:
self._properties.update(self._client_properties)
self._closed = False
self._connected = False
self._close_info = {
'reply_code': 0,
'reply_text': 'first connect',
'class_id': 0,
'method_id': 0
}
self._channels = {0: ConnectionChannel(self, 0)}
login_response = Writer()
login_response.write_table({
'LOGIN': self._user,
'PASSWORD': self._password
})
#stream = BytesIO()
#login_response.flush(stream)
#self._login_response = stream.getvalue()[4:] #Skip the length
#at the beginning
self._login_response = login_response.buffer()[4:]
self._channel_counter = 0
self._channel_max = 65535
self._frame_max = 65535
self._frames_read = 0
self._frames_written = 0
self._strategy = kwargs.get('connection_strategy')
if not self._strategy:
self._strategy = ConnectionStrategy(
self, self._host, reconnect_cb=self._reconnect_cb)
self._strategy.connect()
self._output_frame_buffer = []
@property
def logger(self):
return self._logger
@property
def debug(self):
return self._debug
@property
def frame_max(self):
return self._frame_max
@property
def channel_max(self):
return self._channel_max
@property
def frames_read(self):
'''Number of frames read in the lifetime of this connection.'''
return self._frames_read
@property
def frames_written(self):
'''Number of frames written in the lifetime of this connection.'''
return self._frames_written
@property
def close_info(self):
'''Return dict with information on why this connection is closed. Will
return None if the connections is open.'''
return self._close_info if self._closed else None
def reconnect(self):
'''Reconnect to the configured host and port.'''
self._strategy.connect()
def connect(self, host, port):
'''
Connect to a host and port. Can be called directly, or is called by the
strategy as it tries to find and connect to hosts.
'''
# Clear the connect state immediately since we're no longer connected
# at this point.
self._connected = False
# NOTE: purposefully leave output_frame_buffer alone so that pending writes can
# still occur. this allows the reconnect to occur silently without
# completely breaking any pending data on, say, a channel that was just
# opened.
self._sock = EventSocket(read_cb=self._sock_read_cb,
close_cb=self._sock_close_cb,
error_cb=self._sock_error_cb,
debug=self._debug,
logger=self._logger)
self._sock.settimeout(self._connect_timeout)
if self._sock_opts:
for k, v in self._sock_opts.iteritems():
family, type = k
self._sock.setsockopt(family, type, v)
self._sock.connect((host, port))
self._sock.setblocking(False)
# Only after the socket has connected do we clear this state; closed must
# be False so that writes can be buffered in writePacket(). The closed
# state might have been set to True due to a socket error or a redirect.
self._host = "%s:%d" % (host, port)
self._closed = False
self._close_info = {
'reply_code': 0,
'reply_text': 'failed to connect to %s' % (self._host),
'class_id': 0,
'method_id': 0
}
self._sock.write(PROTOCOL_HEADER)
def disconnect(self):
'''
Disconnect from the current host, but otherwise leave this object "open"
so that it can be reconnected.
'''
self._connected = False
if self._sock != None:
self._sock.close_cb = None
try:
self._sock.close()
except:
self.logger.error("Failed to disconnect socket to %s",
self._host,
exc_info=True)
self._sock = None
def add_reconnect_callback(self, callback):
'''Adds a reconnect callback to the strategy. This can be used to
resubscribe to exchanges, etc.'''
self._strategy.reconnect_callbacks.append(callback)
###
### EventSocket callbacks
###
def _sock_read_cb(self, sock):
'''
Callback when there's data to read on the socket.
'''
try:
self._read_frames()
except:
self.logger.error("Failed to read frames from %s",
self._host,
exc_info=True)
self.close(reply_code=501, reply_text='Error parsing frames')
def _sock_close_cb(self, sock):
"""
Callback when socket closed. This is intended to be the callback when the
closure is unexpected.
"""
self.logger.warning('socket to %s closed unexpectedly', self._host)
self._close_info = {
'reply_code': 0,
'reply_text': 'socket closed unexpectedly to %s' % (self._host),
'class_id': 0,
'method_id': 0
}
# We're not connected any more (we're not closed but we're definitely not
# connected)
self._connected = False
self._sock = None
# Call back to a user-provided close function
self._callback_close()
# Fail and do nothing. If you haven't configured permissions and that's
# why the socket is closing, this keeps us from looping.
self._strategy.fail()
def _sock_error_cb(self, sock, msg, exception=None):
"""
Callback when there's an error on the socket.
"""
self.logger.error('error on connection to %s: %s', self._host, msg)
self._close_info = {
'reply_code': 0,
'reply_text': 'socket error on host %s: %s' % (self._host, msg),
'class_id': 0,
'method_id': 0
}
# we're not connected any more (we're not closed but we're definitely not
# connected)
self._connected = False
self._sock = None
# Call back to a user-provided close function
self._callback_close()
# Fail and try to reconnect, because this is expected to be a transient error.
self._strategy.fail()
self._strategy.next_host()
###
### Connection methods
###
def _next_channel_id(self):
'''Return the next possible channel id. Is a circular enumeration.'''
self._channel_counter += 1
if self._channel_counter >= self._channel_max:
self._channel_counter = 1
return self._channel_counter
def channel(self, channel_id=None):
"""
Fetch a Channel object identified by the numeric channel_id, or
create that object if it doesn't already exist. If channel_id is not
None but no channel exists for that id, will raise InvalidChannel. If
there are already too many channels open, will raise TooManyChannels.
"""
if channel_id is None:
# adjust for channel 0
if len(self._channels) - 1 >= self._channel_max:
raise Connection.TooManyChannels(
"%d channels already open, max %d",
len(self._channels) - 1, self._channel_max)
channel_id = self._next_channel_id()
while channel_id in self._channels:
channel_id = self._next_channel_id()
elif channel_id in self._channels:
return self._channels[channel_id]
else:
raise Connection.InvalidChannel("%s is not a valid channel id",
channel_id)
# Call open() here so that ConnectionChannel doesn't have it called. Could
# also solve this other ways, but it's a HACK regardless.
rval = Channel(self, channel_id)
self._channels[channel_id] = rval
rval.open()
return rval
def close(self, reply_code=0, reply_text='', class_id=0, method_id=0):
'''
Close this connection.
'''
self._close_info = {
'reply_code': reply_code,
'reply_text': reply_text,
'class_id': class_id,
'method_id': method_id
}
self._channels[0].close()
def _close_socket(self):
'''Close the socket.'''
# The assumption here is that we don't want auto-reconnect to kick in if
# the socket is purposefully closed.
self._closed = True
# By the time we hear about the protocol-level closure, the socket may
# have already gone away.
if self._sock != None:
self._sock.close_cb = None
try:
self._sock.close()
except:
self.logger.error('error closing socket')
self._sock = None
def _callback_close(self):
'''Callback to any close handler.'''
if self._close_cb:
try:
self._close_cb()
except SystemExit:
raise
except:
self.logger.error('error calling close callback')
def _read_frames(self):
'''
Read frames from the socket.
'''
# Because of the timer callback to dataRead when we re-buffered, there's a
# chance that in between we've lost the socket. If that's the case, just
# silently return as some code elsewhere would have already notified us.
# That bug could be fixed by improving the message reading so that we consume
# all possible messages and ensure that only a partial message was rebuffered,
# so that we can rely on the next read event to read the subsequent message.
if self._sock is None:
return
data = self._sock.read()
reader = Reader(data)
p_channels = set()
for frame in Frame.read_frames(reader):
if self._debug > 1:
self.logger.debug("READ: %s", frame)
self._frames_read += 1
ch = self.channel(frame.channel_id)
ch.buffer_frame(frame)
p_channels.add(ch)
# Still not clear on what's the best approach here. It seems there's a
# slight speedup by calling this directly rather than delaying, but the
# delay allows for pending IO with higher priority to execute.
self._process_channels(p_channels)
#event.timeout(0, self._process_channels, p_channels)
# HACK: read the buffer contents and re-buffer. Would prefer to pass
# buffer back, but there's no good way of asking the total size of the
# buffer, comparing to tell(), and then re-buffering. There's also no
# ability to clear the buffer up to the current position.
# NOTE: This will be cleared up once eventsocket supports the
# uber-awesome buffering scheme that will utilize mmap.
if reader.tell() < len(data):
self._sock.buffer(data[reader.tell():])
def _process_channels(self, channels):
'''
Walk through a set of channels and process their frame buffer. Will
collect all socket output and flush in one write.
'''
for channel in channels:
channel.process_frames()
def _flush_buffered_frames(self):
# In the rare case (a bug) where this is called but send_frame thinks
# they should be buffered, don't clobber.
frames = self._output_frame_buffer
self._output_frame_buffer = []
for frame in frames:
self.send_frame(frame)
def send_frame(self, frame):
'''
Send a single frame. If there is an output buffer, write to that, else send
immediately to the socket.
'''
if self._closed:
if self._close_info and len(self._close_info['reply_text']) > 0:
raise ConnectionClosed("connection is closed: %s : %s"%\
(self._close_info['reply_code'],self._close_info['reply_text']) )
raise ConnectionClosed("connection is closed")
if self._sock == None or (not self._connected
and frame.channel_id != 0):
self._output_frame_buffer.append(frame)
return
if self._debug > 1:
self.logger.debug("WRITE: %s", frame)
buf = bytearray()
frame.write_frame(buf)
self._sock.write(buf)
self._frames_written += 1
