trying to fix #770. have not reproduced problem, best guess.

sarracenia/moth/amqp.py

@@ -136,7 +136,8 @@ def _msgRawToDict(self, raw_msg) -> sarracenia.Message:
             msg['local_offset'] = 0
             msg['_deleteOnPost'] |= set( ['ack_id', 'exchange', 'local_offset', 'subtopic'])
             if not msg.validate():
-                self.channel.basic_ack(msg['ack_id'])
+                if hasattr(self,channel):
+                    self.channel.basic_ack(msg['ack_id'])
                 logger.error('message acknowledged and discarded: %s' % msg)
                 msg = None
         else:
@@ -411,7 +412,8 @@ def putCleanUp(self) -> None:
                     if self.o['dry_run']:
                         logger.info("deleted exchange (dry run): %s (if unused)" % x)
                     else:
-                        self.channel.exchange_delete(x, if_unused=True)
+                        if hasattr(self,'channel'):
+                            self.channel.exchange_delete(x, if_unused=True)
                         logger.info("deleted exchange: %s" % x)
                 except amqp.exceptions.PreconditionFailed as err:
                     err_msg = str(err).replace("Exchange.delete: (406) PRECONDITION_FAILED - exchange ", "")
@@ -425,10 +427,11 @@ def getCleanUp(self) -> None:
 
         try:
             if self.o['dry_run']:
-                logger.info("deleteing queue (dry run) %s" % self.o['queueName'] )
+                logger.info("deleting queue (dry run) %s" % self.o['queueName'] )
             else:
-                logger.info("deleteing queue %s" % self.o['queueName'] )
-                self.channel.queue_delete(self.o['queueName'])
+                logger.info("deleting queue %s" % self.o['queueName'] )
+                if hasattr(self,'channel'):
+                    self.channel.queue_delete(self.o['queueName'])
         except Exception as err:
             logger.error("failed to {} with {}".format(
                 self.o['broker'].url.hostname, err))
@@ -517,7 +520,8 @@ def ack(self, m: sarracenia.Message) -> None:
         ebo = 1
         while True:
             try:
-                self.channel.basic_ack(m['ack_id'])
+                if hasattr(self, 'channel'): 
+                    self.channel.basic_ack(m['ack_id'])
                 del m['ack_id']
                 m['_deleteOnPost'].remove('ack_id')
                 # Break loop if no exceptions encountered