lowercasing component names for es template

[kgeller]

Correcting fieldset name capitalization when generating the generated es template

[djptek]

Looks good

[ebeahan]

Thanks for looking into this one, @kgeller!

A couple of items I wanted to note.

Testing

We don't have much testing coverage of the component and composable template portions of the Elasticsearch generator, but I think we should add test coverage for this case as we're modifying it a bit; at least some testing coverage for the uppercasing-to-lowercasing handling.

The existing tests are in scripts/tests/test_es_template.py for the ES template generator. The other test cases should be helpful examples, and I think since the casing change is pretty targeted, the nesting data structure can be pretty small. Something like:

        ecs_nested = {
            "Acme": {
                "name": "Acme",
            }
        }

Example shell script

As I was reviewing this change, I realized this example shell script for the composable/component index templates would also use the uppercase filename (e.g. Acme.json).

Maybe we can also add lowercasing of the file names in that example shellcode snippet with a command such as tr or awk?

[ebeahan]

Thanks! Added test looks good 👍