async def _process_notify_interest(self, int_name, int_param, app_param):
"""
Async helper for ``_on_notify_interest()``.
"""
logging.debug(f'received notify interest: {Name.to_str(int_name)}')
topic = int_name[:-2] # remove digest and `notify`
# parse notify interest
app_param = NotifyAppParam.parse(app_param)
publisher_prefix = app_param.publisher_prefix
notify_nonce = app_param.notify_nonce
publisher_fwd_hint = app_param.publisher_fwd_hint
int_param = InterestParam()
if publisher_fwd_hint:
# support only 1 forwarding hint now
int_param.forwarding_hint = [(0x0, publisher_fwd_hint.name)]
# send msg interest, retransmit 3 times
msg_int_name = publisher_prefix + ['msg'] + topic + [
Component.from_bytes(notify_nonce)
]
n_retries = 3
# de-duplicate notify interests of the same nonce
if notify_nonce in self.nonce_processed:
logging.info(
f'Received duplicate notify interest for nonce {notify_nonce}')
return
self.nonce_processed.add(notify_nonce)
aio.ensure_future(self._erase_subsciber_state_after(notify_nonce, 60))
while n_retries > 0:
try:
logging.debug(
f'sending msg interest: {Name.to_str(msg_int_name)}')
data_name, meta_info, msg = await self.app.express_interest(
msg_int_name, int_param=int_param)
break
except InterestNack as e:
logging.debug(f'Nacked with reason: {e.reason}')
await aio.sleep(1)
n_retries -= 1
except InterestTimeout:
logging.debug(f'Timeout')
n_retries -= 1
if msg == None:
return
# pass msg to application
logging.info(f'received subscribed msg: {Name.to_str(msg_int_name)}')
self.topic_to_cb[topic](bytes(msg))
# acknowledge notify interest with an empty data packet
logging.debug(f'acknowledging notify interest {Name.to_str(int_name)}')
self.app.put_data(int_name, None)
def test_forwarding_hint():
name = '/local/ndn/prefix'
int_param = InterestParam()
int_param.nonce = 0x01020304
int_param.forwarding_hint = [(0x87, '/name/A'),
(0x02, Name.from_str('/ndn/B')),
(0x12, b'\x07\x0d\x08\x0bshekkuenseu')]
interest = make_interest(name, int_param)
assert (interest ==
b'\x05\x55\x07\x14\x08\x05local\x08\x03ndn\x08\x06prefix'
b'\x1e\x33'
b'\x1f\x0e\x1e\x01\x87\x07\x09\x08\x04name\x08\x01A'
b'\x1f\x0d\x1e\x01\x02\x07\x08\x08\x03ndn\x08\x01B'
b'\x1f\x12\x1e\x01\x12\x07\r\x08\x0bshekkuenseu'
b'\x0a\x04\x01\x02\x03\x04\x0c\x02\x0f\xa0')
async def _process_notify_interest(self, int_name, int_param, app_param):
"""
Async helper for ``_on_notify_interest()``.
"""
logging.debug(f'received notify interest: {Name.to_str(int_name)}')
topic = int_name[:-2] # remove digest and `notify`
# parse notify interest
app_param = PubSub.NotifyAppParam.parse(app_param)
publisher_prefix = app_param.publisher_prefix
nonce = app_param.nonce
publisher_fwd_hint = app_param.publisher_fwd_hint
int_param = InterestParam()
if publisher_fwd_hint:
int_param.forwarding_hint = publisher_fwd_hint
# send msg interest, retransmit 3 times
msg_int_name = publisher_prefix + ['msg', str(nonce)]
n_retries = 3
while n_retries > 0:
try:
logging.debug(
f'sending msg interest: {Name.to_str(msg_int_name)}')
data_name, meta_info, msg = await self.app.express_interest(
msg_int_name, int_param=int_param)
break
except InterestNack as e:
logging.debug(f'Nacked with reason: {e.reason}')
await aio.sleep(1)
except InterestTimeout:
logging.debug(f'Timeout')
if msg == None:
return
# pass msg to application
logging.info(f'received subscribed msg: {Name.to_str(msg_int_name)}')
self.topic_to_cb[topic](bytes(msg))
# acknowledge notify interest with an empty data packet
logging.debug(f'acknowledging notify interest {Name.to_str(int_name)}')
self.app.put_data(int_name, None)