Reconnect failure :: publisher

[madkote]

Please review the following publisher example.

import logging
import sys
import time

import stomp

def stomp_connect(conn, user='guest', password='guest'):
    conn.connect(login=user, passcode=password, wait=True)

class ReconnectListener(stomp.ConnectionListener):
        def __init__(self, conn):
            self.conn = conn

        def on_error(self, headers, message):
            print('received an error "%s"' % message)

        def on_message(self, headers, message):
            print('received a message "%s"' % message)
            for x in range(10):
                print(x)
                time.sleep(1)
            print('processed message')

        def on_disconnected(self):
            print('disconnected')
            stomp_connect(self.conn)

def demo_publish():
    print()
    print('+----------------------------------------+')
    print('| Single ActiveMQ publisher example         |')
    print('+----------------------------------------+')
    #
    #
    host_and_ports = [('localhost', 61613)]
    attempts = 30
    name_queue = 'test_queue'
    #
    #
    conn = stomp.Connection(
        host_and_ports=host_and_ports,
        reconnect_attempts_max=attempts
    )
    conn.set_listener('', ReconnectListener(conn))
    stomp_connect(conn)
    #
    #
    counter = 0
    sleep = 13.0
    try:
        while True:
            try:
                print('>> send', counter)
                conn.send(
                    name_queue,
                    'message #%s, time=%s' % (counter, time.time())
                )
                print('>>> >>> sleep')
                counter += 1
                time.sleep(sleep)
            except KeyboardInterrupt:
                break
    finally:
        print('> disconnect')
        conn.disconnect()
        print('> disconnect done')

if __name__ == '__main__':
    logging.basicConfig(stream=sys.stdout, level=logging.DEBUG)
    demo_publish()

python: 3.7
stomp: 6.0.0

Normally, the pubilisher sends all messages. If you shutdown the ActiveMQ server, and starts again (with docker-compose), then reconnect want work....

python demo_send.py 
INFO:stomp.py:attempt reconnection (True, None, 0)
INFO:stomp.py:Attempting connection to host localhost, port 61613
INFO:stomp.py:Established connection to host localhost, port 61613
INFO:stomp.py:Starting receiver loop (<Thread(Thread-1, started daemon 140657043883776)>)
INFO:stomp.py:Created thread <Thread(Thread-1, started daemon 140657043883776)> using func <function default_create_thread at 0x7fed4604acb0>
DEBUG:stomp.py:Sending frame: [b'STOMP', b'\n', b'accept-version:1.1\n', b'login:guest\n', b'passcode:guest\n', b'\n', b'\x00']
DEBUG:stomp.py:Received frame: 'CONNECTED', headers={'server': 'ActiveMQ/5.15.6', 'heart-beat': '0,0', 'session': 'ID:activemq-46317-1583420355347-3:1', 'version': '1.1'}, body=''
DEBUG:stomp.py:Heartbeats calculated (0, 0)
>> send 0
DEBUG:stomp.py:Sending frame: [b'SEND', b'\n', b'content-length:34\n', b'destination:test_queue\n', b'\n', b'message #0, time=1583420399.842412', b'\x00']
>>> >>> sleep
DEBUG:stomp.py:nothing received, raising CCE
INFO:stomp.py:Receiver loop ended
disconnected
INFO:stomp.py:attempt reconnection (True, None, 0)
INFO:stomp.py:Attempting connection to host localhost, port 61613
INFO:stomp.py:Established connection to host localhost, port 61613
INFO:stomp.py:Starting receiver loop (<Thread(Thread-2, started daemon 140657035491072)>)
INFO:stomp.py:Created thread <Thread(Thread-2, started daemon 140657035491072)> using func <function default_create_thread at 0x7fed4604acb0>
DEBUG:stomp.py:nothing received, raising CCE
DEBUG:stomp.py:Sending frame: [b'STOMP', b'\n', b'accept-version:1.1\n', b'login:guest\n', b'passcode:guest\n', b'\n', b'\x00']
ERROR:stomp.py:Error sending frame
Traceback (most recent call last):
  File "/home/madkote/demo-stomp/venv/lib/python3.7/site-packages/stomp/transport.py", line 630, in send
    self.socket.sendall(encoded_frame)
OSError: [Errno 9] Bad file descriptor
INFO:stomp.py:Receiver loop ended
Exception in thread Thread-1:
Traceback (most recent call last):
  File "/usr/lib/python3.7/threading.py", line 926, in _bootstrap_inner
    self.run()
  File "/usr/lib/python3.7/threading.py", line 870, in run
    self._target(*self._args, **self._kwargs)
  File "/home/madkote/demo-stomp/venv/lib/python3.7/site-packages/stomp/transport.py", line 360, in __receiver_loop
    self.notify("disconnected")
  File "/home/madkote/demo-stomp/venv/lib/python3.7/site-packages/stomp/transport.py", line 230, in notify
    notify_func()
  File "demo_send.py", line 43, in on_disconnected
    stomp_connect(self.conn)
  File "demo_send.py", line 24, in stomp_connect
    conn.connect(login=user, passcode=password, wait=True)
  File "/home/madkote/demo-stomp/venv/lib/python3.7/site-packages/stomp/connect.py", line 162, in connect
    Protocol11.connect(self, *args, **kwargs)
  File "/home/madkote/demo-stomp/venv/lib/python3.7/site-packages/stomp/protocol.py", line 332, in connect
    self.send_frame(cmd, headers)
  File "/home/madkote/demo-stomp/venv/lib/python3.7/site-packages/stomp/protocol.py", line 244, in send_frame
    self.transport.transmit(frame)
  File "/home/madkote/demo-stomp/venv/lib/python3.7/site-packages/stomp/transport.py", line 271, in transmit
    self.send(packed_frame)
  File "/home/madkote/demo-stomp/venv/lib/python3.7/site-packages/stomp/transport.py", line 634, in send
    raise e
  File "/home/madkote/demo-stomp/venv/lib/python3.7/site-packages/stomp/transport.py", line 630, in send
    self.socket.sendall(encoded_frame)
OSError: [Errno 9] Bad file descriptor

>> send 1
DEBUG:stomp.py:Sending frame: [b'SEND', b'\n', b'content-length:33\n', b'destination:test_queue\n', b'\n', b'message #1, time=1583420412.85417', b'\x00']
> disconnect
  File "demo_send.py", line 89, in <module>
    demo_publish()
  File "demo_send.py", line 83, in demo_publish
    conn.disconnect()
  File "/home/madkote/demo-stomp/venv/lib/python3.7/site-packages/stomp/connect.py", line 172, in disconnect
    Protocol11.disconnect(self, receipt, headers, **keyword_headers)
  File "/home/madkote/demo-stomp/venv/lib/python3.7/site-packages/stomp/protocol.py", line 351, in disconnect
    traceback.print_stack()
DEBUG:stomp.py:Not sending disconnect, already disconnected
> disconnect done
Traceback (most recent call last):
  File "demo_send.py", line 89, in <module>
    demo_publish()
  File "demo_send.py", line 74, in demo_publish
    'message #%s, time=%s' % (counter, time.time())
  File "/home/madkote/demo-stomp/venv/lib/python3.7/site-packages/stomp/protocol.py", line 398, in send
    self.send_frame(CMD_SEND, headers, body)
  File "/home/madkote/demo-stomp/venv/lib/python3.7/site-packages/stomp/protocol.py", line 244, in send_frame
    self.transport.transmit(frame)
  File "/home/madkote/demo-stomp/venv/lib/python3.7/site-packages/stomp/transport.py", line 271, in transmit
    self.send(packed_frame)
  File "/home/madkote/demo-stomp/venv/lib/python3.7/site-packages/stomp/transport.py", line 636, in send
    raise exception.NotConnectedException()
stomp.exception.NotConnectedException

The sleep value is high enough to prevent sending during reconnection and the issue occurs before actual sending.

[madkote]

Is the intention reconnect is good only for listener connections correct?

[madkote]

One more comment: also when synchronizing send and reconnect -> the issue is same.