def do_extra_handshake(self, request):
"""Do extra checking in WebSocket handshake.
Select a handler based on request.uri and call its
web_socket_do_extra_handshake function.
Args:
request: mod_python request.
Raises:
DispatchException: when handler was not found
AbortedByUserException: when user handler abort connection
HandshakeException: when opening handshake failed
"""
handler_suite = self.get_handler_suite(request.ws_resource)
if handler_suite is None:
raise DispatchException('No handler for: %r' % request.ws_resource)
do_extra_handshake_ = handler_suite.do_extra_handshake
try:
do_extra_handshake_(request)
except handshake.AbortedByUserException as e:
# Re-raise to tell the caller of this function to finish this
# connection without sending any error.
self._logger.debug('%s', util.get_stack_trace())
raise
except Exception as e:
util.prepend_message_to_exception(
'%s raised exception for %s: ' % (
_DO_EXTRA_HANDSHAKE_HANDLER_NAME,
request.ws_resource),
e)
raise handshake.HandshakeException(e, common.HTTP_STATUS_FORBIDDEN)
def transfer_data(self, request):
"""Let a handler transfer_data with a Web Socket client.
Select a handler based on request.ws_resource and call its
web_socket_transfer_data function.
Args:
request: mod_python request.
"""
unused_do_extra_handshake, transfer_data_ = self._handler(request)
try:
try:
request.client_terminated = False
request.server_terminated = False
transfer_data_(request)
except msgutil.ConnectionTerminatedException, e:
util.prepend_message_to_exception(
'client initiated closing handshake for %s: ' %
(request.ws_resource), e)
raise
except Exception, e:
print 'exception: %s' % type(e)
util.prepend_message_to_exception(
'%s raised exception for %s: ' %
(_TRANSFER_DATA_HANDLER_NAME, request.ws_resource), e)
raise
def transfer_data(self, request):
"""Let a handler transfer_data with a Web Socket client.
Select a handler based on request.ws_resource and call its
web_socket_transfer_data function.
Args:
request: mod_python request.
"""
unused_do_extra_handshake, transfer_data_ = self._handler(request)
try:
try:
request.client_terminated = False
request.server_terminated = False
transfer_data_(request)
except msgutil.ConnectionTerminatedException, e:
util.prepend_message_to_exception(
'client initiated closing handshake for %s: ' % (
request.ws_resource),
e)
raise
except Exception, e:
print 'exception: %s' % type(e)
util.prepend_message_to_exception(
'%s raised exception for %s: ' % (
_TRANSFER_DATA_HANDLER_NAME, request.ws_resource),
e)
raise
def _write(request, bytes):
try:
request.connection.write(bytes)
except Exception, e:
util.prepend_message_to_exception(
'Failed to send message to %r: ' %
(request.connection.remote_addr, ), e)
raise
def transfer_data(self, request):
"""Let a handler transfer_data with a WebSocket client.
Select a handler based on request.ws_resource and call its
web_socket_transfer_data function.
Args:
request: mod_python request.
Raises:
DispatchException: when handler was not found
AbortedByUserException: when user handler abort connection
"""
# TODO(tyoshino): Terminate underlying TCP connection if possible.
try:
if mux.use_mux(request):
mux.start(request, self)
else:
handler_suite = self.get_handler_suite(request.ws_resource)
if handler_suite is None:
raise DispatchException('No handler for: %r' %
request.ws_resource)
transfer_data_ = handler_suite.transfer_data
transfer_data_(request)
if not request.server_terminated:
request.ws_stream.close_connection()
# Catch non-critical exceptions the handler didn't handle.
except handshake.AbortedByUserException as e:
self._logger.debug('%s', util.get_stack_trace())
raise
except msgutil.BadOperationException as e:
self._logger.debug('%s', e)
request.ws_stream.close_connection(
common.STATUS_INTERNAL_ENDPOINT_ERROR)
except msgutil.InvalidFrameException as e:
# InvalidFrameException must be caught before
# ConnectionTerminatedException that catches InvalidFrameException.
self._logger.debug('%s', e)
request.ws_stream.close_connection(common.STATUS_PROTOCOL_ERROR)
except msgutil.UnsupportedFrameException as e:
self._logger.debug('%s', e)
request.ws_stream.close_connection(common.STATUS_UNSUPPORTED_DATA)
except stream.InvalidUTF8Exception as e:
self._logger.debug('%s', e)
request.ws_stream.close_connection(
common.STATUS_INVALID_FRAME_PAYLOAD_DATA)
except msgutil.ConnectionTerminatedException as e:
self._logger.debug('%s', e)
except Exception as e:
# Any other exceptions are forwarded to the caller of this
# function.
util.prepend_message_to_exception(
'%s raised exception for %s: ' % (
_TRANSFER_DATA_HANDLER_NAME, request.ws_resource),
e)
raise
def _write(request, bytes):
try:
request.connection.write(bytes)
except Exception, e:
util.prepend_message_to_exception(
'Failed to send message to %r: ' %
(request.connection.remote_addr,),
e)
raise
def _write(self, bytes_to_write):
"""Writes given bytes to connection. In case we catch any exception,
prepends remote address to the exception message and raise again.
"""
try:
self._request.connection.write(bytes_to_write)
except Exception as e:
util.prepend_message_to_exception(
'Failed to send message to %r: ' %
(self._request.connection.remote_addr, ), e)
raise
def _write(self, bytes):
"""Writes given bytes to connection. In case we catch any exception,
prepends remote address to the exception message and raise again.
"""
try:
self._request.connection.write(bytes)
except Exception, e:
util.prepend_message_to_exception(
'Failed to send message to %r: ' %
(self._request.connection.remote_addr,),
e)
raise
def do_extra_handshake(self, request):
"""Do extra checking in Web Socket handshake.
Select a handler based on request.uri and call its
web_socket_do_extra_handshake function.
Args:
request: mod_python request.
"""
do_extra_handshake_, unused_transfer_data = self._handler(request)
try:
do_extra_handshake_(request)
except Exception, e:
util.prepend_message_to_exception(
'%s raised exception for %s: ' %
(_DO_EXTRA_HANDSHAKE_HANDLER_NAME, request.ws_resource), e)
raise
def do_extra_handshake(self, request):
"""Do extra checking in Web Socket handshake.
Select a handler based on request.uri and call its
web_socket_do_extra_handshake function.
Args:
request: mod_python request.
"""
do_extra_handshake_, unused_transfer_data = self._handler(request)
try:
do_extra_handshake_(request)
except Exception, e:
util.prepend_message_to_exception(
'%s raised exception for %s: ' % (
_DO_EXTRA_HANDSHAKE_HANDLER_NAME,
request.ws_resource),
e)
raise
class Dispatcher(object):
"""Dispatches WebSocket requests.
This class maintains a map from resource name to handlers.
"""
def __init__(self,
root_dir,
scan_dir=None,
allow_handlers_outside_root_dir=True):
"""Construct an instance.
Args:
root_dir: The directory where handler definition files are
placed.
scan_dir: The directory where handler definition files are
searched. scan_dir must be a directory under root_dir,
including root_dir itself. If scan_dir is None,
root_dir is used as scan_dir. scan_dir can be useful
in saving scan time when root_dir contains many
subdirectories.
allow_handlers_outside_root_dir: Scans handler files even if their
canonical path is not under root_dir.
"""
self._logger = util.get_class_logger(self)
self._handler_suite_map = {}
self._source_warnings = []
if scan_dir is None:
scan_dir = root_dir
if not os.path.realpath(scan_dir).startswith(
os.path.realpath(root_dir)):
raise DispatchException('scan_dir:%s must be a directory under '
'root_dir:%s.' % (scan_dir, root_dir))
self._source_handler_files_in_dir(root_dir, scan_dir,
allow_handlers_outside_root_dir)
def add_resource_path_alias(self, alias_resource_path,
existing_resource_path):
"""Add resource path alias.
Once added, request to alias_resource_path would be handled by
handler registered for existing_resource_path.
Args:
alias_resource_path: alias resource path
existing_resource_path: existing resource path
"""
try:
handler_suite = self._handler_suite_map[existing_resource_path]
self._handler_suite_map[alias_resource_path] = handler_suite
except KeyError:
raise DispatchException('No handler for: %r' %
existing_resource_path)
def source_warnings(self):
"""Return warnings in sourcing handlers."""
return self._source_warnings
def do_extra_handshake(self, request):
"""Do extra checking in WebSocket handshake.
Select a handler based on request.uri and call its
web_socket_do_extra_handshake function.
Args:
request: mod_python request.
Raises:
DispatchException: when handler was not found
AbortedByUserException: when user handler abort connection
HandshakeException: when opening handshake failed
"""
handler_suite = self.get_handler_suite(request.ws_resource)
if handler_suite is None:
raise DispatchException('No handler for: %r' % request.ws_resource)
do_extra_handshake_ = handler_suite.do_extra_handshake
try:
do_extra_handshake_(request)
except handshake.AbortedByUserException, e:
raise
except Exception, e:
util.prepend_message_to_exception(
'%s raised exception for %s: ' %
(_DO_EXTRA_HANDSHAKE_HANDLER_NAME, request.ws_resource), e)
raise handshake.HandshakeException(e, common.HTTP_STATUS_FORBIDDEN)
got_exception = False
if not abort:
_write(request, '\xff\x00')
# timeout of 20 seconds to get the client's close frame ack
initial_time = time()
end_time = initial_time + 20
while time() < end_time:
try:
receive_message(request)
except ConnectionTerminatedException, e:
got_exception = True
sleep(1)
request.server_terminated = True
if got_exception:
util.prepend_message_to_exception(
'client initiated closing handshake for %s: ' %
(request.ws_resource), e)
raise ConnectionTerminatedException
# TODO: 3. close the WebSocket connection.
# note: mod_python Connection (mp_conn) doesn't have close method.
def send_message(request, message):
"""Send message.
Args:
request: mod_python request.
message: unicode string to send.
Raises:
ConnectionTerminatedException: when server already terminated.
"""
self._logger.debug('%s', e)
request.ws_stream.close_connection(
common.STATUS_PROTOCOL_ERROR)
except msgutil.UnsupportedFrameException, e:
self._logger.debug('%s', e)
request.ws_stream.close_connection(
common.STATUS_UNSUPPORTED_DATA)
except stream.InvalidUTF8Exception, e:
self._logger.debug('%s', e)
request.ws_stream.close_connection(
common.STATUS_INVALID_FRAME_PAYLOAD_DATA)
except msgutil.ConnectionTerminatedException, e:
self._logger.debug('%s', e)
except Exception, e:
util.prepend_message_to_exception(
'%s raised exception for %s: ' %
(_TRANSFER_DATA_HANDLER_NAME, request.ws_resource), e)
raise
except handshake.AbortedByUserException, e:
self._logger.info('%s', e)
return False
def _get_logger_from_class(c):
return logging.getLogger('%s.%s' % (c.__module__, c.__name__))
def _configure_logging(options):
logging.addLevelName(common.LOGLEVEL_FINE, 'FINE')
def test_prepend_message_to_exception(self):
exc = Exception('World')
self.assertEqual('World', str(exc))
util.prepend_message_to_exception('Hello ', exc)
self.assertEqual('Hello World', str(exc))
def test_prepend_message_to_exception(self):
exc = Exception('World')
self.assertEqual('World', str(exc))
util.prepend_message_to_exception('Hello ', exc)
self.assertEqual('Hello World', str(exc))
got_exception = False
if not abort:
_write(request, '\xff\x00')
# timeout of 20 seconds to get the client's close frame ack
initial_time = time()
end_time = initial_time + 20
while time() < end_time:
try:
receive_message(request)
except ConnectionTerminatedException, e:
got_exception = True
sleep(1)
request.server_terminated = True
if got_exception:
util.prepend_message_to_exception(
'client initiated closing handshake for %s: ' % (
request.ws_resource),
e)
raise ConnectionTerminatedException
# TODO: 3. close the WebSocket connection.
# note: mod_python Connection (mp_conn) doesn't have close method.
def send_message(request, message):
"""Send message.
Args:
request: mod_python request.
message: unicode string to send.
Raises:
ConnectionTerminatedException: when server already terminated.
"""
self._logger.debug('%s', e)
request.ws_stream.close_connection(common.STATUS_PROTOCOL_ERROR)
except msgutil.UnsupportedFrameException, e:
self._logger.debug('%s', e)
request.ws_stream.close_connection(common.STATUS_UNSUPPORTED_DATA)
except stream.InvalidUTF8Exception, e:
self._logger.debug('%s', e)
request.ws_stream.close_connection(
common.STATUS_INVALID_FRAME_PAYLOAD_DATA)
except msgutil.ConnectionTerminatedException, e:
self._logger.debug('%s', e)
except Exception, e:
# Any other exceptions are forwarded to the caller of this
# function.
util.prepend_message_to_exception(
'%s raised exception for %s: ' % (
_TRANSFER_DATA_HANDLER_NAME, request.ws_resource),
e)
raise
def passive_closing_handshake(self, request):
"""Prepare code and reason for responding client initiated closing
handshake.
"""
handler_suite = self.get_handler_suite(request.ws_resource)
if handler_suite is None:
return _default_passive_closing_handshake_handler(request)
return handler_suite.passive_closing_handshake(request)
def get_handler_suite(self, resource):
"""Retrieves two handlers (one for extra handshake processing, and one