Filter manager fails if given array when expected single term

[mvar]

I have following configuration:

ongr_filter_manager:
    managers:
        product_list:
            filters:
                - manufacturer
            repository: 'es.manager.default.product'
    filters:
        choice:
            manufacturer: 
                request_field: 'man'
                field: manufacturer

Usually with this config URL looks like this:

/list?man=Swiss+Legend

but if for some reason you pass man as array

/list?man[]=Swiss+Legend

filter manager fails hard. It will return 5xx code "Uncaught PHP Exception" because of "BadRequest400Exception" thrown from Elasticsearch client.

To fail in this case is OK, but we should return HttpException with 4xx error code by ourself.

The real issue here is that we allow filter manager to send invalid query to Elasticsearch. Filter manager should have some kind of validation and make sure that user data does not generate invalid queries.