I am writing a filter plugin for Logstash and I'm following this guide.
So, I have finished the code, written everything and done some testing with rspec. Now, I have built the gem with
gem build logstash-filter-e164.gemspec and sent it to the server where we run Logstash.
But, now running
bin/logstash-plugin install logstash-filter-e164-0.2.0.gem, I get the following error:
Validating /tmp/logstash-filter-e164-0.2.0.gem Installing logstash-filter-e164 ERROR: Installation Aborted, message: undefined method `=' for #<Bundler::Settings:0x28e94c2> Did you mean? 
I have no idea what to do here, because it seems to be something from Bundler. I am using jruby-188.8.131.52.