def process_content(self, content: Content,
r_msg: ReliableMessage) -> Optional[Content]:
res = super().process_content(content=content, r_msg=r_msg)
if res is None:
# respond nothing
return None
if isinstance(res, HandshakeCommand):
# urgent command
return res
# if isinstance(i_msg.content, ReceiptCommand):
# receiver = msg.receiver
# if receiver.type == NetworkID.Station:
# # no need to respond receipt to station
# return None
# check receiver
receiver = r_msg.receiver
user = self.facebook.select_user(receiver=receiver)
assert user is not None, 'receiver error: %s' % receiver
# pack message
env = Envelope.create(sender=user.identifier, receiver=r_msg.sender)
i_msg = InstantMessage.create(head=env, body=res)
# normal response
self.messenger.send_message(msg=i_msg)
# DON'T respond to station directly
return None
def send_content(self,
sender: ID,
receiver: ID,
content: Content,
callback: Optional[Callback] = None,
priority: int = 0) -> bool:
"""
Send message content to receiver
:param sender: sender ID
:param receiver: receiver ID
:param content: message content
:param callback: if needs callback, set it here
:param priority: task priority (smaller is faster)
:return: True on success
"""
if sender is None:
# Application Layer should make sure user is already login before it send message to server.
# Application layer should put message into queue so that it will send automatically after user login
user = self.facebook.current_user
assert user is not None, 'failed to get current user'
sender = user.identifier
# pack and send
env = Envelope.create(sender=sender, receiver=receiver)
msg = InstantMessage.create(head=env, body=content)
return self.messenger.send_message(msg=msg,
callback=callback,
priority=priority)
def __pack_message(self, content: Content,
receiver: ID) -> Optional[ReliableMessage]:
sender = g_station.identifier
env = Envelope.create(sender=sender, receiver=receiver)
i_msg = InstantMessage.create(head=env, body=content)
s_msg = g_messenger.encrypt_message(msg=i_msg)
if s_msg is None:
self.error('failed to encrypt msg: %s' % i_msg)
return None
return g_messenger.sign_message(msg=s_msg)
def send_content(self,
sender: ID,
receiver: ID,
content: Content,
callback: Optional[Callback] = None,
priority: int = 0) -> bool:
"""
Send message content to receiver
:param sender: sender ID
:param receiver: receiver ID
:param content: message content
:param callback: if needs callback, set it here
:param priority: task priority (smaller is faster)
:return: True on success
"""
env = Envelope.create(sender=sender, receiver=receiver)
msg = InstantMessage.create(head=env, body=content)
return self.send_message(msg=msg, callback=callback, priority=priority)
def __send_content(self, content: Content, receiver: ID) -> bool:
station = self.get_context(key='station')
if station is None:
user = self.facebook.current_user
if user is None:
return False
sender = user.identifier
else:
sender = station.identifier
env = Envelope.create(sender=sender, receiver=receiver)
i_msg = InstantMessage.create(head=env, body=content)
s_msg = self.encrypt_message(msg=i_msg)
if s_msg is None:
# failed to encrypt message
return False
r_msg = self.sign_message(msg=s_msg)
assert r_msg is not None, 'failed to sign message: %s' % s_msg
r_msg.delegate = self
self.dispatcher.deliver(msg=r_msg)
return True
def send_report(self, text: str, receiver: ID) -> bool:
if self.sender is None:
self.error('sender not set yet')
return False
timestamp = int(time.time())
content = TextContent(text=text)
env = Envelope.create(sender=self.sender,
receiver=receiver,
time=timestamp)
i_msg = InstantMessage.create(head=env, body=content)
s_msg = self.messenger.encrypt_message(msg=i_msg)
assert s_msg is not None, 'failed to report: %s, %s' % (receiver, text)
r_msg = self.messenger.sign_message(msg=s_msg)
if r_msg.delegate is None:
r_msg.delegate = self.messenger
# try for online user
sessions = self.session_server.active_sessions(identifier=receiver)
if len(sessions) > 0:
self.debug('%s is online(%d), try to push report: %s' %
(receiver, len(sessions), text))
success = 0
for sess in sessions:
if sess.push_message(r_msg):
success = success + 1
else:
self.error(
'failed to push report via connection (%s, %s)' %
sess.client_address)
if success > 0:
self.debug(
'report pushed to activated session(%d) of user: %s' %
(success, receiver))
return True
# store in local cache file
self.debug('%s is offline, store report: %s' % (receiver, text))
self.database.store_message(r_msg)
# push notification
dispatcher = self.messenger.dispatcher
return dispatcher.push(sender=self.sender,
receiver=receiver,
message=text)
def deliver_message(self,
msg: ReliableMessage) -> Optional[ReliableMessage]:
""" Deliver message to the receiver, or broadcast to neighbours """
s_msg = self.messenger.verify_message(msg=msg)
if s_msg is None:
# signature error?
return None
# FIXME: check deliver permission
res = None # self.filter.check_deliver(msg=msg)
if res is None:
# delivering is allowed, call dispatcher to deliver this message
res = self.dispatcher.deliver(msg=msg)
# pack response
if res is not None:
user = self.facebook.current_user
env = Envelope.create(sender=user.identifier, receiver=msg.sender)
i_msg = InstantMessage.create(head=env, body=res)
s_msg = self.messenger.encrypt_message(msg=i_msg)
if s_msg is None:
raise AssertionError('failed to respond to: %s' % msg.sender)
return self.messenger.sign_message(msg=s_msg)
def download(self, content: FileContent, password: SymmetricKey,
msg: SecureMessage):
url = content.url
if url is None or url.find('://') < 0:
# download URL not found
return False
i_msg = InstantMessage.create(head=msg.envelope, body=content)
# download from CDN
encrypted = self.messenger.download_data(url=url, msg=i_msg)
if encrypted is None or len(encrypted) == 0:
# save symmetric key for decrypting file data after download from CDN
content.password = password
return False
else:
# decrypt file data
data = password.decrypt(data=encrypted)
if data is None or len(data) == 0:
raise ValueError('failed to decrypt file data with key: %s' %
password)
content.data = data
content.url = None
return True
def __process_group_message(
self, msg: ReliableMessage) -> Optional[ReliableMessage]:
"""
Separate group message and forward them one by one
if members not found,
drop this message and query group info from sender;
if 'keys' found in group message,
update them to cache;
remove non-exists member from 'keys
split group message with members, forward them
:param msg:
:return: ReliableMessage as result
"""
s_msg = self.verify_message(msg=msg)
if s_msg is None:
# signature error?
return None
sender = msg.sender
receiver = msg.receiver
if not self.facebook.exists_member(member=sender, group=receiver):
if not self.facebook.is_owner(member=sender, group=receiver):
# not allow, kick it out
cmd = GroupCommand.expel(group=receiver, member=sender)
sender = self.facebook.current_user.identifier
receiver = msg.sender
env = Envelope.create(sender=sender, receiver=receiver)
i_msg = InstantMessage.create(head=env, body=cmd)
s_msg = self.encrypt_message(msg=i_msg)
if s_msg is None:
self.error('failed to encrypt message: %s' % i_msg)
self.suspend_message(msg=i_msg)
return None
return self.sign_message(msg=s_msg)
members = self.facebook.members(receiver)
if members is None or len(members) == 0:
# members not found for this group,
# query it from sender
res = GroupCommand.query(group=receiver)
else:
# check 'keys'
keys = msg.get('keys')
if keys is not None:
# remove non-exists members from 'keys'
expel_list = []
for item in keys:
if item == 'digest':
self.info('key digest: %s' % keys[item])
continue
m = ID.parse(identifier=item)
if m not in members:
self.info('remove non-exists member: %s' % item)
expel_list.append(m)
if len(expel_list) > 0:
# send 'expel' command to the sender
cmd = GroupCommand.expel(group=receiver,
members=expel_list)
g_messenger.send_content(sender=None,
receiver=sender,
content=cmd)
# update key map
self.__key_cache.update_keys(keys=keys,
sender=sender,
group=receiver)
# split and forward group message,
# respond receipt with success or failed list
res = self.__split_group_message(msg=msg, members=members)
# pack response
if res is not None:
sender = self.facebook.current_user.identifier
receiver = msg.sender
env = Envelope.create(sender=sender, receiver=receiver)
i_msg = InstantMessage.create(head=env, body=res)
s_msg = self.encrypt_message(msg=i_msg)
if s_msg is None:
self.error('failed to encrypt message: %s' % i_msg)
self.suspend_message(msg=i_msg)
return None
return self.sign_message(msg=s_msg)