For those who are struggeling with the install of plugins and having them install on spinning up a container I have wrote this
mount the file from your volumn outside the container
to Container Path: /usr/share/logstash/config/plugins.sh
add a post argument
#!binbash echo running post install scripts for plugins..; logstash-plugin install logstash-filter-sentimentalizer logstash-plugin install logstash-input-mysql echo finished post install scripts for plugins..; sleep 1 exec logstash
the exec logstash is what kicks logstash into starting after the plugin installs.