--path.settings doesn't appear to be respected

[mpalmer]

$ docker run -v /srv/docker/logstash:/logstash --rm docker.elastic.co/logstash/logstash:5.2.2 logstash --path.settings /logstash/logstash.yml
WARNING: Could not find logstash.yml which is typically located in $LS_HOME/config or /etc/logstash. You can specify the path using --path.settings. Continuing using the defaults
Could not find log4j2 configuration at path /logstash/log4j2.properties. Using default config which logs to console
(etc etc etc)

The file I'm referencing exists, is readable by logstash, and so on:

$ docker run -v /srv/docker/logstash:/logstash --rm docker.elastic.co/logstash/logstash:5.2.2 cat /logstash/logstash.yml
pipeline:
  workers: 64
  batch:
    size: 250
path:
  config: '/logstash/logstash.conf'
  queue: '/logstash/queue'
  reload:
    automatic: true
$ docker run -v /srv/docker/logstash:/logstash --rm docker.elastic.co/logstash/logstash:5.2.2 id
uid=1000(logstash) gid=1000(logstash) groups=1000(logstash)

If I instead set LS_SETTINGS_DIR appropriately, everything is happy:

$ docker run -v /srv/docker/logstash:/logstash -e LS_SETTINGS_DIR=/logstash --rm docker.elastic.co/logstash/logstash:5.2.2
Could not find log4j2 configuration at path /logstash/log4j2.properties. Using default config which logs to console
(etc etc etc)

[jarpy]

It looks like the flag is failing because you are specifying the full path to logstash.yml, but the argument to --path.settings should be the containing directory.

eg:

docker run -v /srv/docker/logstash:/logstash --rm docker.elastic.co/logstash/logstash:5.2.2 logstash --path.settings /logstash

I personally think the error message is a little misleading, and implies that --path.settings is not set, when it's just set incorrectly.

From the docs:

--path.settings SETTINGS_DIR
  
  Set the directory containing the logstash.yml settings file as well as the log4j logging configuration. This 
  can also be set through the LS_SETTINGS_DIR environment variable. The default is the config directory 
  under Logstash home.

[mpalmer]

D'oh! Reading-the-docs-carefully fail. I definitely agree that a better error message would help, but apart from that this is entirely my bad (and the issue closed). Thanks for the gentle cluebat.

[jarpy]

No worries. Thanks for reporting back.