KAFKA-10822 Force some stdout from system tests for Travis

tests/kafkatest/tests/core/downgrade_test.py

@@ -120,11 +120,11 @@ def test_upgrade_and_downgrade(self, version, compression_types, security_protoc
         self.setup_services(kafka_version, compression_types, security_protocol, static_membership)
         self.await_startup()
 
-        self.logger.info("First pass bounce - rolling upgrade")
+        print("First pass bounce - rolling upgrade", flush=True) # Force some stdout for Travis
         self.upgrade_from(kafka_version)
         self.run_validation()
 
-        self.logger.info("Second pass bounce - rolling downgrade")
+        print("Second pass bounce - rolling downgrade", flush=True) # Force some stdout for Travis
         self.downgrade_to(kafka_version)
         self.run_validation()
         assert self.kafka.check_protocol_errors(self)

tests/kafkatest/tests/core/replication_test.py

@@ -52,13 +52,15 @@ def clean_bounce(test, broker_type):
     """Chase the leader of one partition and restart it cleanly."""
     for i in range(5):
         prev_broker_node = broker_node(test, broker_type)
+        print("clean_bounce on " + str(prev_broker_node.account), flush=True) # Force some stdout for Travis
         test.kafka.restart_node(prev_broker_node, clean_shutdown=True)
 
 
 def hard_bounce(test, broker_type):
     """Chase the leader and restart it with a hard kill."""
     for i in range(5):
         prev_broker_node = broker_node(test, broker_type)
+        print("hard_bounce on " + str(prev_broker_node.account), flush=True) # Force some stdout for Travis
         test.kafka.signal_node(prev_broker_node, sig=signal.SIGKILL)
 
         # Since this is a hard kill, we need to make sure the process is down and that

tests/kafkatest/tests/core/security_rolling_upgrade_test.py

@@ -65,6 +65,7 @@ def roll_in_secured_settings(self, client_protocol, broker_protocol):
         # Roll cluster to include inter broker security protocol.
         self.kafka.setup_interbroker_listener(broker_protocol)
         self.bounce()
+        print("succeed in bouncing kafka cluster to include inter broker security protocol", flush=True) # Force some stdout for Travis
 
         # Roll cluster to disable PLAINTEXT port
         self.kafka.close_port(SecurityConfig.PLAINTEXT)

tests/kafkatest/tests/core/upgrade_test.py

@@ -55,17 +55,17 @@ def perform_upgrade(self, from_kafka_version, to_message_format_version=None):
         # Not trying to detect a problem here leads to failure in the ensuing Kafka roll, which would be a less
         # intuitive failure than seeing a problem here, so detect ZooKeeper upgrade problems before involving Kafka.
         self.zk.describe(self.topic)
-        self.logger.info("First pass bounce - rolling upgrade")
         for node in self.kafka.nodes:
+            print("First pass bounce - rolling upgrade on " + str(node.account), flush=True) # Force some stdout for Travis
             self.kafka.stop_node(node)
             node.version = DEV_BRANCH
             node.config[config_property.INTER_BROKER_PROTOCOL_VERSION] = from_kafka_version
             node.config[config_property.MESSAGE_FORMAT_VERSION] = from_kafka_version
             self.kafka.start_node(node)
             self.wait_until_rejoin()
 
-        self.logger.info("Second pass bounce - remove inter.broker.protocol.version config")
         for node in self.kafka.nodes:
+            print("Second pass bounce - remove inter.broker.protocol.version config from " + str(node.account), flush=True) # Force some stdout for Travis
             self.kafka.stop_node(node)
             del node.config[config_property.INTER_BROKER_PROTOCOL_VERSION]
             if to_message_format_version is None: