def send(self, message, cid=None):
""" Called internally in preparation for sending messages to the client
This method pre-processes the message then passes it to the overridden
outgoing method.
Keyword arguments:
message -- a dict of message values to be marshalled and sent
cid -- (optional) an associated id
"""
serialized = self.serialize(message, cid)
if serialized is not None:
if self.png == "png":
# TODO: png compression on outgoing messages
# encode message
pass
fragment_list = None
if self.fragment_size != None and len(serialized) > self.fragment_size:
mid = message.get("id", None)
# TODO: think about splitting into fragments that have specified size including header-fields!
# --> estimate header size --> split content into fragments that have the requested overall size, rather than requested content size
fragment_list = Fragmentation(self).fragment(message, self.fragment_size, mid )
# fragment list not empty -> send fragments
if fragment_list != None:
for fragment in fragment_list:
self.outgoing(json.dumps(fragment))
# okay to use delay here (sender's send()-function) because rosbridge is sending next request only to service provider when last one had finished)
# --> if this was not the case this delay needed to be implemented in service-provider's (meaning message receiver's) send_message()-function in rosbridge_tcp.py)
time.sleep(self.delay_between_messages)
# else send message as it is
else:
self.outgoing(serialized)
time.sleep(self.delay_between_messages)