Exception in thread Thread-MonitorBatchPublisher:
Traceback (most recent call last):
  File "/usr/local/lib/python3.7/site-packages/google/api_core/grpc_helpers.py", line 57, in error_remapped_callable
    return callable_(*args, **kwargs)
  File "/usr/local/lib/python3.7/site-packages/grpc/_channel.py", line 547, in __call__
    return _end_unary_response_blocking(state, call, False, None)
  File "/usr/local/lib/python3.7/site-packages/grpc/_channel.py", line 466, in _end_unary_response_blocking
    raise _Rendezvous(state, None, None, deadline)
grpc._channel._Rendezvous: <_Rendezvous of RPC that terminated with:
status = StatusCode.UNAVAILABLE
details = "Name resolution failure"
debug_error_string = "{"created":"@1546984814.701239700","description":"Failed to create subchannel","file":"src/core/ext/filters/client_channel/client_channel.cc","file_line":2706,"referenced_errors":[{"created":"@1546984814.701230600","description":"Name resolution failure","file":"src/core/ext/filters/client_channel/client_channel.cc","file_line":3035,"grpc_status":14}]}"
>

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "/usr/local/lib/python3.7/site-packages/google/api_core/retry.py", line 179, in retry_target
    return target()
  File "/usr/local/lib/python3.7/site-packages/google/api_core/timeout.py", line 214, in func_with_timeout
    return func(*args, **kwargs)
  File "/usr/local/lib/python3.7/site-packages/google/api_core/grpc_helpers.py", line 59, in error_remapped_callable
    six.raise_from(exceptions.from_grpc_error(exc), exc)
  File "<string>", line 3, in raise_from
google.api_core.exceptions.ServiceUnavailable: 503 Name resolution failure

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "/usr/local/lib/python3.7/threading.py", line 917, in _bootstrap_inner
    self.run()
  File "/usr/local/lib/python3.7/threading.py", line 865, in run
    self._target(*self._args, **self._kwargs)
  File "/usr/local/lib/python3.7/site-packages/google/cloud/pubsub_v1/publisher/_batch/thread.py", line 254, in monitor
    return self._commit()
  File "/usr/local/lib/python3.7/site-packages/google/cloud/pubsub_v1/publisher/_batch/thread.py", line 201, in _commit
    response = self._client.api.publish(self._topic, self._messages)
  File "/usr/local/lib/python3.7/site-packages/google/cloud/pubsub_v1/gapic/publisher_client.py", line 410, in publish
    request, retry=retry, timeout=timeout, metadata=metadata
  File "/usr/local/lib/python3.7/site-packages/google/api_core/gapic_v1/method.py", line 143, in __call__
    return wrapped_func(*args, **kwargs)
  File "/usr/local/lib/python3.7/site-packages/google/api_core/retry.py", line 270, in retry_wrapped_func
    on_error=on_error,
  File "/usr/local/lib/python3.7/site-packages/google/api_core/retry.py", line 199, in retry_target
    last_exc,
  File "<string>", line 3, in raise_from
google.api_core.exceptions.RetryError: Deadline of 0.0s exceeded while calling functools.partial(<function _wrap_unary_errors.<locals>.error_remapped_callable at 0x7f764c2b3b70>, messages {
}
, metadata=[('x-goog-api-client', 'gl-python/3.7.0 grpc/1.17.1 gax/1.7.0 gapic/0.39.1')]), last exception: 503 Name resolution failure

Traceback (most recent call last):
  File "<string>", line 15, in <module>
  File "/usr/local/lib/python3.7/site-packages/google/cloud/pubsub_v1/futures.py", line 110, in result
    err = self.exception(timeout=timeout)
  File "/usr/local/lib/python3.7/site-packages/google/cloud/pubsub_v1/futures.py", line 133, in exception
    raise exceptions.TimeoutError("Timed out waiting for result.")
concurrent.futures._base.TimeoutError: Timed out waiting for result.