* Obtain key owner information matching a given filter criterion.

Key owners in the system are different types of entities: Participant, Mediator, Domain Topology Manager and Sequencer. The present method allows to define a filter to search for a key owner using filters on (asOf, domain, ownerType, owner)

The response is a sequence of (domain, ownerType, owner, keys) where keys is a sequence of (fingerprint, bytes, key purpose). As such, we can use this method to export currently used signing or encryption public keys.

This method is quite general, as depending on the arguments, very different results can be obtained.

Using OwnerType = 'Participant' allows to query for all participants. Using OwnerType = 'Sequencer' allows to query for all sequencers defined.

* Obtain information about a certain set of active parties matching a given filter criterion.

The request allows to filter per (domain, party, asOf) where the domain and party argument are used in order to filter the result list using the startsWith method on the respective resulting string.

As such, if you just need to do a lookup, then define a precise filter. Given the uniqueness of the identifiers (and the fact that the identifiers contain key fingerprints), we should only ever get a single result back if we are doing a precise lookup.

The response is a sequence of tuples (party, domain, participant, privilege, trust-level). The response is restricted to active parties and their active participants.