class Broker():
_BINDING_IP = '127.0.0.1'
_BINDING_PORT = 65432
_consumerSelector = None
_QUEUE_SIZE = 2
_messageQueue = None
_messageHandler = None
_MAX_BUFFER_SIZE = 4096
def __init__(self):
self._messageQueue = queue.Queue(self._QUEUE_SIZE)
self._messageHandler = MessageHandler()
def _initiateConsumerSelector(self):
self._consumerSelector = selectors.DefaultSelector()
lsock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
lsock.bind((self._BINDING_IP, self._BINDING_PORT))
lsock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
lsock.listen()
print('listening on', (self._BINDING_IP, self._BINDING_PORT))
lsock.setblocking(False)
self._consumerSelector.register(lsock, selectors.EVENT_READ, data=None)
self._acceptConnections()
def _register(self, sock):
conn, addr = sock.accept() # Should be ready to read
print('accepted connection from', addr)
conn.setblocking(False)
data = types.SimpleNamespace(addr=addr, outb=b'')
events = selectors.EVENT_WRITE
self._consumerSelector.register(conn, events, data=data)
def _acceptConnections(self):
while True:
events = self._consumerSelector.select(timeout=None)
for key, mask in events:
if key.data is None:
self._register(key.fileobj)
else:
self._service_connection(key, mask)
def _sendAll(self, socket, data):
dataLength = len(data)
while dataLength > self._MAX_BUFFER_SIZE:
self._safeSend(socket, data[:self._MAX_BUFFER_SIZE])
dataLength -= self._MAX_BUFFER_SIZE
data = data[self._MAX_BUFFER_SIZE:]
#send remaining bytes
self._safeSend(socket, data)
def _safeSend(self, socket, data):
try:
sent = socket.send(data) # Should be ready to write
except BlockingIOError:
# Resource temporarily unavailable (errno EWOULDBLOCK)
print('Resource temporarily unavailable: trying again...')
self._safeSend(socket, data)
except BrokenPipeError:
#ToDo try to send the entire data again
print('connection lost')
self._consumerSelector.unregister(socket)
socket.close()
def _service_connection(self, key, mask):
sock = key.fileobj
dataOverSocket = key.data
if mask & selectors.EVENT_WRITE:
'''if not dataOverSocket.outb:
data = self._pop()'''
data = self._pop()
'''if self._messageQueue.qsize() == 0:
print('ended at:', now = datetime.now().time())'''
if data:
#dataOverSocket.outb = data
self._sendAll(sock, data)
#print('sending', repr(data), 'to', dataOverSocket.addr)
#dataOverSocket.outb = dataOverSocket.outb[sent:]
def start(self):
initThread = threading.Thread(target=self._initiateConsumerSelector)
initThread.start()
#self._initiateConsumerSelector()
def push(self, data=None, meta=None, isByteData=False):
if data == None:
print('No data to push')
pass
packet = self._messageHandler.createMessage(data, meta, isByteData)
#print('pushing', packet, ': current queue size', self._messageQueue.qsize())
self._messageQueue.put(packet, block=True)
def _pop(self):
return self._messageQueue.get(block=True)
