[receiver/discovery] Combine matching conditions with different statuses

[dmitryax]

Define the status of match conditions as a field instead of a map key. This way, we make the status evaluation deterministic. The first matching rule defines the status of the discovery endpoint. Without this reorganization, it's unclear which status wins if matching rules with different statuses overlap.

For example the following configuration:

    receivers:
      prometheus_simple:
        rule: type == "hostport" and command contains "otelcol"
        resource_attributes:
          one.key: one.value
          two.key: two.value
        status:
          metrics:
            successful:
            - regexp: ^otelcol_process_uptime$
              first_only: true
              log_record:
                body: Successfully connected to prometheus server

must be changed to

    receivers:
      prometheus_simple:
        rule: type == "hostport" and command contains "otelcol"
        resource_attributes:
          one.key: one.value
          two.key: two.value
        status:
          metrics:
            - status: successful
              regexp: ^otelcol_process_uptime$
              first_only: true
              log_record:
                body: Successfully connected to prometheus server

[dmitryax]

This can be changed to something like status_detection as the next step to avoid different status fields

[samiura]

Is this change absolutely necessary for entity events?

[dmitryax]

It's unnecessary, but having two status fields is confusing. The higher level status doesn't seem like a good name for what it's defining. Do you have any concerns with renaming it?

[dmitryax]

Giving that we are significantly changing this interface, I don't see why we need to restrain any further changes

[samiura]

Understood!

[samiura]

I think I would go with your change as it makes things more deterministic.