Here's how I've started: Get the existing template, 'de-nest' it by one level:
$ curl 'localhost:9200/_template/logstash?pretty' > logstash.template.json $ sed -i '' -e '$d' -e '2d' logstash.template.json
Here's where I'm stuck. I want to add in the configuration values from above, but I'm not sure where in that file to put them. Do I follow the dot pattern with curly brackets? e.g. Is it it in settings -> merge -> scheduler -> max_thread_count ?
If I don't get any advice I guess I'll hack around with some testing.
Later on, I plan to overwrite the existing template. I've tried this with a test template and it seems to work.
$ curl -XPUT 'http://localhost:9200/_template/logstash?pretty' -d @logstash.template.json