filebeat 5.3 regression - console output returning crit errors then stops logging to output

[gbolo]

There seems to be some regression with the latest version of filebeat in regards to console output.

Example:

# t.sh
for i in $(seq 1 20); do echo $i; sleep 1; done

# filebeat.yaml
filebeat:
  shutdown_timeout: 0s
  prospectors:
    - input_type: stdin
      encoding: utf-8

output.console:
  codec.format:
    string: '%{[message]}'

logging.level: critical
logging.to_files: false
logging.to_syslog: false

filebeat version 5.3.0 (amd64), libbeat 5.3.0
Notice how it stops at 6 and logs a CRIT to stderr

$ sh t.sh | ./filebeat -c filebeast.yaml -e
1
2017/04/18 19:11:46.026826 console.go:83: CRIT Unable to publish events to console: <nil>
2
2017/04/18 19:11:46.026872 console.go:83: CRIT Unable to publish events to console: <nil>
3
2017/04/18 19:11:46.026881 console.go:83: CRIT Unable to publish events to console: <nil>
4
2017/04/18 19:11:46.026893 console.go:83: CRIT Unable to publish events to console: <nil>
5
2017/04/18 19:11:46.026901 console.go:83: CRIT Unable to publish events to console: <nil>
6
2017/04/18 19:11:46.026909 console.go:83: CRIT Unable to publish events to console: <nil>

filebeat version 5.2.1 (amd64), libbeat 5.2.1
The formating is different because codec.format is not available on this version

sh t.sh | filebeat -c /tmp/filebeast-stdin2.yaml -e
{"@timestamp":"2017-04-18T19:12:35.603Z","beat":{"hostname":"ee86c6ebade2","name":"ee86c6ebade2","version":"5.2.1"},"input_type":"stdin","message":"1","offset":0,"source":"","type":"log"}
{"@timestamp":"2017-04-18T19:12:36.600Z","beat":{"hostname":"ee86c6ebade2","name":"ee86c6ebade2","version":"5.2.1"},"input_type":"stdin","message":"2","offset":0,"source":"","type":"log"}
{"@timestamp":"2017-04-18T19:12:37.601Z","beat":{"hostname":"ee86c6ebade2","name":"ee86c6ebade2","version":"5.2.1"},"input_type":"stdin","message":"3","offset":0,"source":"","type":"log"}
{"@timestamp":"2017-04-18T19:12:38.601Z","beat":{"hostname":"ee86c6ebade2","name":"ee86c6ebade2","version":"5.2.1"},"input_type":"stdin","message":"4","offset":0,"source":"","type":"log"}
{"@timestamp":"2017-04-18T19:12:39.602Z","beat":{"hostname":"ee86c6ebade2","name":"ee86c6ebade2","version":"5.2.1"},"input_type":"stdin","message":"5","offset":0,"source":"","type":"log"}
{"@timestamp":"2017-04-18T19:12:40.602Z","beat":{"hostname":"ee86c6ebade2","name":"ee86c6ebade2","version":"5.2.1"},"input_type":"stdin","message":"6","offset":0,"source":"","type":"log"}
{"@timestamp":"2017-04-18T19:12:41.603Z","beat":{"hostname":"ee86c6ebade2","name":"ee86c6ebade2","version":"5.2.1"},"input_type":"stdin","message":"7","offset":0,"source":"","type":"log"}
{"@timestamp":"2017-04-18T19:12:42.603Z","beat":{"hostname":"ee86c6ebade2","name":"ee86c6ebade2","version":"5.2.1"},"input_type":"stdin","message":"8","offset":0,"source":"","type":"log"}
{"@timestamp":"2017-04-18T19:12:43.603Z","beat":{"hostname":"ee86c6ebade2","name":"ee86c6ebade2","version":"5.2.1"},"input_type":"stdin","message":"9","offset":0,"source":"","type":"log"}
{"@timestamp":"2017-04-18T19:12:44.604Z","beat":{"hostname":"ee86c6ebade2","name":"ee86c6ebade2","version":"5.2.1"},"input_type":"stdin","message":"10","offset":0,"source":"","type":"log"}
{"@timestamp":"2017-04-18T19:12:45.604Z","beat":{"hostname":"ee86c6ebade2","name":"ee86c6ebade2","version":"5.2.1"},"input_type":"stdin","message":"11","offset":0,"source":"","type":"log"}
{"@timestamp":"2017-04-18T19:12:46.605Z","beat":{"hostname":"ee86c6ebade2","name":"ee86c6ebade2","version":"5.2.1"},"input_type":"stdin","message":"12","offset":0,"source":"","type":"log"}
{"@timestamp":"2017-04-18T19:12:47.605Z","beat":{"hostname":"ee86c6ebade2","name":"ee86c6ebade2","version":"5.2.1"},"input_type":"stdin","message":"13","offset":0,"source":"","type":"log"}
{"@timestamp":"2017-04-18T19:12:48.605Z","beat":{"hostname":"ee86c6ebade2","name":"ee86c6ebade2","version":"5.2.1"},"input_type":"stdin","message":"14","offset":0,"source":"","type":"log"}
{"@timestamp":"2017-04-18T19:12:49.606Z","beat":{"hostname":"ee86c6ebade2","name":"ee86c6ebade2","version":"5.2.1"},"input_type":"stdin","message":"15","offset":0,"source":"","type":"log"}
{"@timestamp":"2017-04-18T19:12:50.606Z","beat":{"hostname":"ee86c6ebade2","name":"ee86c6ebade2","version":"5.2.1"},"input_type":"stdin","message":"16","offset":0,"source":"","type":"log"}
{"@timestamp":"2017-04-18T19:12:51.607Z","beat":{"hostname":"ee86c6ebade2","name":"ee86c6ebade2","version":"5.2.1"},"input_type":"stdin","message":"17","offset":0,"source":"","type":"log"}
{"@timestamp":"2017-04-18T19:12:52.607Z","beat":{"hostname":"ee86c6ebade2","name":"ee86c6ebade2","version":"5.2.1"},"input_type":"stdin","message":"18","offset":0,"source":"","type":"log"}
{"@timestamp":"2017-04-18T19:12:53.608Z","beat":{"hostname":"ee86c6ebade2","name":"ee86c6ebade2","version":"5.2.1"},"input_type":"stdin","message":"19","offset":0,"source":"","type":"log"}
{"@timestamp":"2017-04-18T19:12:54.608Z","beat":{"hostname":"ee86c6ebade2","name":"ee86c6ebade2","version":"5.2.1"},"input_type":"stdin","message":"20","offset":0,"source":"","type":"log"}

[andrewkroh]

It looks like we lost a return statement after signaling success. This is at https://github.com/elastic/beats/blob/v5.3.0/libbeat/outputs/console/console.go#L80-L81.

This affects 5.3. Earlier versions look OK.