def __create(self) -> None:
if path.exists('server.db'):
return
try:
exceptions.log_info("creating the db table")
if not self._connect():
raise exceptions.ConnectionException(
"Failed to connect the db.")
client_tableStr = '''CREATE TABLE ClientTbl
(ID VARBINARY(16) PRIMARY KEY,
PublicKey VARBINARY(160) NOT NULL,
UName VARCHAR(255) NOT NULL UNIQUE,
LastSeen TEXT)'''
message_table = '''CREATE TABLE message_table
(ID INTEGER PRIMARY KEY AUTOINCREMENT,
ToClient VARBINARY(16) ,
FromClient VARBINARY(16) ,
Type TEXT,
Content BLOB,
FOREIGN KEY(ToClient,FromClient) REFERENCES ClientTbl(ID,ID))'''
curs = self._conn.cursor()
curs.execute(client_tableStr)
curs.execute(message_table)
except sqlite3.Error as e:
exceptions.log_error("failed to create the db tables.", e)
print("failed creating the data base tables.")
finally:
curs.close()
def accept(self):
"""accept a connection request from clients"""
conn, self._target_address = self.__sock.accept()
exceptions.log_info("accept connection: " + str(conn) + ", from: " +
str(self._target_address))
conn.setblocking(False)
self.__read(conn)
def __read(self, conn: socket.socket) -> None:
"""read the data from the socket and handle the request, if valid.
conn :param - connection from client
Exception :raises - if connection broken or message is too big or
the data received isn't correlate with the protocol
None :returns"""
header_len = 22
try:
data = conn.recv(self.__max_pack__) # Should be ready
if len(data) < header_len: # header_len should be <= len(data)
print('closing', conn)
self.__selector.unregister(conn)
conn.close()
return None
fields = struct.unpack('<' + str(self.__UID_LEN__) + 's B B I',
data[:header_len])
exceptions.log_info("received: " + str(fields) + "...")
usr_id, ver, code, payload_size = fields
data = data[header_len:]
if ver != 2: # change this condition to allow old version to get treatment
raise exceptions.VersionException(
"Error: the client, version is: ", ver, ".")
if code not in self.__requests_tbl.values():
raise exceptions.InvalidCodeException(
"Error: the code, ", code, ", doesn't match any request.")
if code == self.__requests_tbl['rgstr']:
self.register(data, payload_size)
return None
elif code == self.__requests_tbl[
'usr_lst'] or code == self.__requests_tbl['pull_msg']:
if payload_size:
raise exceptions.DataException("no payload expected!")
if code == self.__requests_tbl['pull_msg']:
self.__send(self.__response_tbl['msgs_pulled'],
dbClasses.MsgTbl().pull(usr_id))
return None
self.__send(self.__response_tbl['usr_lst_returned'],
dbClasses.ClientTbl().get_usrs(usr_id))
return
elif code == self.__requests_tbl['usr_key']:
# other_uid = struct.unpack('>' + str(UID_LEN) + 's', data[:UID_LEN])
self.__send(self.__response_tbl['usr_key_returned'],
dbClasses.ClientTbl().get_usr(
data[:self.__UID_LEN__])) # [::-1]))
return None
# send msg
self.__handle_message(conn, usr_id, data)
except exceptions.ConnectionException as conExcept: # as conExcept:
exceptions.log_error(
"while reading from " + str(self._target_address), conExcept)
return
except Exception as e:
exceptions.log_error("", e)
self.__send(self.__response_tbl['gnrl_err'])
finally:
if conn:
conn.close()
def connect(address):
if not address:
return None
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
try:
exceptions.log_info("trying to connect: " + str((address[0], 8080)))
sock.connect((address[0], 8080))
except Exception as e:
raise exceptions.ConnectionException(e)
return sock
def get_usrs(self, uid):
self.update(uid)
if self._connect():
try:
exceptions.log_info("loading the users list.")
cur = self._conn.cursor()
cur.execute("SELECT ID, UName FROM ClientTbl WHERE ID <> ?",
[uid])
return cur.fetchall()
except Exception as ex:
exceptions.log_error("failed to get clients from the db.", ex)
finally:
if cur:
cur.close()
if self._conn:
self._conn.close()
return []
def register(self, data: str, payloadSize: int):
name, pub_key = 256, 160
if payloadSize not in range(pub_key + 1, pub_key + name):
raise exceptions.RegistrationException(
"the payload size is out of range, " + str(payloadSize))
fields = struct.unpack(
'<' + str(payloadSize - pub_key) + 's ' + str(pub_key) + 's',
data[:payloadSize])
# fields = [x[::-1] for x in fields]
name, pub_key = fields
usr_id = uuid.uuid4()
client = dbClasses.ClientTbl()
if not client.insert(usr_id.bytes, name.lower(), pub_key):
raise exceptions.RegistrationException("the user with id: ",
usr_id, "already exist")
self.__send(self.__response_tbl['rgstr_succeeded'], usr_id)
exceptions.log_info("The client " + name + " just register.")
return
def __handle_content(self, data: bytes, content_size: int,
conn: socket.socket):
content = data
left_to_read = content_size - len(data)
if left_to_read > 0:
rec_cnt = len(data)
BLOCK_SIZE = 1 << 14
while content_size > rec_cnt:
bytes_to_read = min(BLOCK_SIZE, abs(content_size - rec_cnt))
tmp = conn.recv(bytes_to_read)
if not tmp:
break
content += tmp
rec_cnt += len(tmp)
exceptions.log_info("received " + str(len(content)) +
' bytes, from ' + str(content_size) +
' bytes.')
elif left_to_read < 0:
content = content[:content_size]
return struct.unpack('<' + str(len(content)) + 's', content)
def insert(self, usr_id, uname, pubkey):
if self._connect():
try:
exceptions.log_info("inserting the user, to the db")
cur = self._conn.cursor()
cur.execute(
"INSERT INTO ClientTbl(ID,PublicKey,UName,LastSeen) VALUES(?,?,?,?)",
[usr_id, pubkey, uname,
datetime.now()])
self._conn.commit()
return True
except Exception as ex:
exceptions.log_error("failed to insert client to the db.", ex)
self._conn.rollback()
finally:
if cur:
cur.close()
if self._conn:
self._conn.close()
return False
def insert(self, from_usr, to_usr, msg_type, msg_cntnt) -> int:
ClientTbl().update(from_usr)
exceptions.log_info("inserting message to the db")
if self._connect():
try:
cur = self._conn.cursor()
cur.execute(
"INSERT INTO message_table(FromClient, ToClient, Type, Content) VALUES(?,?,?,?)",
[from_usr, to_usr,
str(msg_type), msg_cntnt])
self._conn.commit()
cur.execute("SELECT COUNT(ID) FROM message_table")
return cur.fetchone()[0]
except Exception as ex:
exceptions.log_error("failed to insert message to the db", ex)
self._conn.rollback()
finally:
if cur:
cur.close()
if self._conn:
self._conn.close()
return 0
def __handle_message(self, conn: socket.socket, usr_id: bytes,
data: bytes) -> None:
"""handle message from the server's client and save it until the target pull it
conn :param - connection from client
usr_id :param - source client uuid
data :param - the message data
Exception :raises - if connection broken or message is too big or data isn't correlate with the protocol
None :returns"""
exceptions.log_info("start to handle message.")
other_uid, msg_type, content_size = self.__handle_header(data)
data = data[
self.__UID_LEN__ +
5:] # ToDo: move to using index instead of copy substring into data
exceptions.log_info("the message info is: " +
str((msg_type, content_size)))
self.__handle_msg_type(msg_type, content_size, usr_id, other_uid)
content = self.__handle_content(data, content_size, conn)
msg_id = dbClasses.MsgTbl().insert(usr_id, other_uid, msg_type,
content[0])
if msg_id == 0:
self.__send(self.__response_tbl['gnrl_err'])
return
self.__send(self.__response_tbl['msg_received'], [other_uid, msg_id])
def pull(self, usr_id):
ClientTbl().update(usr_id)
exceptions.log_info("pulling messages from the db")
if self._connect():
try:
cur = self._conn.cursor()
cur.execute(
"SELECT FromClient, ID, Type, Content FROM message_table WHERE ToClient = ?",
[usr_id])
pulled_msgs = cur.fetchall()
# id_lst = [x[1] for x in pulled_msgs]
# cur.execute("DELETE FROM message_table WHERE ID IN ({})".format(", ".join("?" * len(id_lst))), id_lst)
self._conn.commit()
return pulled_msgs
except Exception as ex:
exceptions.log_error(
"failed to pull client messages from the db.", ex)
self._conn.rollback()
finally:
if cur:
cur.close()
if self._conn:
self._conn.close()
return ""
def __send(self, code, payload=None):
"""send the response to the client
code :param - response code
payload :param - response payload
Exception :raises if failed to connect or message is too big or
the response data isn't correlate with the protocol
the length of the response :returns"""
exceptions.log_info("sending the response: " + str(code))
if not self._target_address:
raise Exception("error: client address lost, can't send messages.")
if code not in self.__response_tbl.values():
raise exceptions.InvalidCodeException(
f"Error: the code, {code}, is not valid.")
to_send = struct.pack('<B H', self.__VER__,
code) # pack the version and the respond code
if code == self.__response_tbl['gnrl_err']:
to_send += struct.pack('<I', 0)
elif code == self.__response_tbl[
'msgs_pulled'] or code == self.__response_tbl[
'usr_lst_returned']:
tmp = b''
if code == self.__response_tbl['usr_lst_returned']:
for rec in payload:
name_len = len(rec[1])
tmp += struct.pack(
'<' + str(self.__UID_LEN__) + 's' + str(name_len) +
's ' + str(self.__NAME_LEN__ - name_len) + 'x', rec[0],
rec[1])
else:
for rec in payload:
tmp += struct.pack(
'<' + str(self.__UID_LEN__) + 's I c I ' +
str(len(rec[3])) + 's', rec[0], rec[1],
int(rec[2]).to_bytes(1, 'little'), len(rec[3]), rec[3])
to_send += struct.pack('<I', len(tmp)) + tmp
elif code != self.__response_tbl['gnrl_err'] and not payload:
raise exceptions.MissingDataException(
"Error: expect to receive some data to send, but received None."
)
elif code == self.__response_tbl['msg_received']:
tmp = struct.pack('<' + str(self.__UID_LEN__) + 's I', payload[0],
payload[1])
to_send += struct.pack('<I', len(tmp)) + tmp
elif code == self.__response_tbl['usr_key_returned']:
to_send += struct.pack(
'<I ' + str(self.__UID_LEN__) + 's ' +
str(self.__PUB_KEY_SIZE__) + 's',
self.__PUB_KEY_SIZE__ + self.__UID_LEN__, *payload)
elif code == self.__response_tbl['rgstr_succeeded']:
to_send += struct.pack('< I ' + str(self.__UID_LEN__) + 's',
self.__UID_LEN__, payload.bytes) # [::-1])
padding_size = self.__max_pack__ - len(to_send)
if padding_size > 0:
to_send += struct.pack(str(padding_size) + 'x')
sock: socket
try:
sock = connect(self._target_address)
except Exception as e:
exceptions.log_info(f"failed to connect to {self._target_address}",
e)
exceptions.log_info("sending " + str(len(to_send)) + " bytes.")
if sock.sendall(to_send) == 0:
raise exceptions.BrokenConnectionException(
"socket connection broken.")
sock.close()
return len(to_send)
