A small Bash-script, a jq-script, and Perl-script to do a basic conversion from Elasticsearch legacy templates to composable templates.
As an example I have include a legacy template from Elastic 7.17 that can be converted like this:
$ ./convert2composable.sh legacy_template_1.json
Converting legacy_template_1.json => legacy_template_1.json.new
Processed 1 files.
If you are satified with the new files, use the command
rename ".json.new" ".json" *.json.new
to replace the old JSON files with the new.