[Elastic Agent] Enforce validation on namespace

[ph]

In Kibana we are adding validation on top of the namespace to remove the possibility to create invalid index name.
We should have the same rules applied on the elastic-agent.

[elasticmachine]

Pinging @elastic/ingest-management (Team:Ingest Management)

[michalpristas]

should be done at configuration parse time:

beats/x-pack/elastic-agent/pkg/agent/application/filters/stream_checker.go

Line 173 in f06bcc5

func matchesIndexContraints(namespace string) bool {

[ph]

@michalpristas Can you confirm that the validation match between Kibana and the Agent?

[michalpristas]

i will verify what they are using, we took rules from ES documentation so if they did the same we should be fine. i will confirm

[michalpristas]

the validation rules used in kibana is more relaxed I left a comment there in a PR https://github.com/elastic/kibana/pull/75381/files#r476228944 and created issue to align elastic/kibana#75846

[ph]

@michalpristas I think both are incorrect, see my comment in https://github.com/elastic/kibana/pull/75381/files#r476416054 Can you take a lead and synchronize with @jen-huang to have unique validation for both?

[jen-huang]

I followed up in elastic/kibana#75846 (comment).

[michalpristas]

Closing, fixed by #21406