[FEAT] Filter aggregations about kt-search

[jelle-blaauw]

I was actually able to come up with this:

class FilterQuery : ESQuery(name = "filter")

class FilterAgg(
    block: (FilterQuery.() -> ESQuery)
) : AggQuery("filter") {
    init {
        val config = FilterQuery()
        val query = block.invoke(config)
        config[query.name] = query
        put(name, config)
    }
}

which can be used as follows:

agg("my-agg-name", FilterAgg {
    bool {
        must(
            nested {
                path = "someField"
                query = bool {
                    must(
                        exists("someField"),
                        terms("someField.somePath", "someValue"),
                    )
                }
            }
        )
    }
})

It can probably improved, and there still needs to be a clean way to retrieve the results, but at least it works.

[jillesvangurp]

Cool thanks! That looks like it should work. When I find some time, I'll squeeze in a pull request. Might be a while because I'm super busy right now.