NPE in GelfAppender.append kills the host app about logback-gelf HOT 6 CLOSED

I figured out how I managed to produce this NPE. I was using an environment variable for the graylog server param, like this

    <graylog2ServerHost>${GRAYLOG_SERVER_IP}</graylog2ServerHost>

and it was not set, so the value GRAYLOG_SERVER_IP_IS_UNDEFINED comes in, which causes this exception

Caused by: java.lang.IllegalStateException: Unknown host: GRAYLOG_SERVER_IP_IS_UNDEFINED: unknown error. Make sure you have specified the 'graylog2ServerHost' property correctly in your logback.xml'
at at me.moocar.logbackgelf.InternetUtils.getInetAddress(InternetUtils.java:53)
at at me.moocar.logbackgelf.GelfAppender.initExecutor(GelfAppender.java:89)

Then subsequent appends throw NPE

from logback-gelf.

Perhaps a good middle ground here is to add a regex for graylog2ServerHost to ensure that it matches an IP. Then, if it doesn't, print a warning. PRs welcome :) otherwise I'll eventually get to it.

from logback-gelf.

I see. What if somebody wanted to use a dns name? As it happens my plan was to move my system to do that, so apps can keep logging if I cycle my graylog server and it gets a new ip address.

from logback-gelf.

yeah, good point. I guess this would he hard to protect against. Out of interest, what part of the stack is setting the value to "GRAYLOG_SERVER_IP_IS_UNDEFINED"? I've never seen that before.

from logback-gelf.

I think its logback.

from logback-gelf.

Closing as error message is better after merging #49

from logback-gelf.