This charm will manage a individual custom config file for logstash. This will allow you to use the logstash charm with custom configurations.
juju deploy logstash-conf-d logstash-output-file
juju add-relation logstash logstash-output-file
juju config logstash-output-file config="output { fiele { path=> '/var/log/myfile '}}"
This will result in a config file named /etc/logstash/conf.d/logstash-output-file.conf
The content of the 'config' field is directly written in the config file. No templating or syntax check is performed. It must be a valid logstash configuration.