I am not sure anyone tested mixed database types, have you tested it? Does it work?
I'm not sure what happens to a LevelDB backed peer when it receives directions to build indices which only exist in CouchDB.
Regarding discovery, there is no roadmap for this, no.
Having said that, discovery fetches information from the gossip membership module, and it is fairly straightforward to add any type of information about the peer to the information being replicated and returned to the user.
In the code, there is a message called Properties which is simply replicated and is set by the peer:
So if you want, you can extend it yourself and then set its value in a similar manner to how it's done for chaincodes , and then you get this information from the discovery query automatically.
From: fabric@... <fabric@...> on behalf of Joao Antunes <joao.antunes@...>
Sent: Wednesday, August 10, 2022 3:25 AM
To: fabric@... <fabric@...>
Subject: [EXTERNAL] [Hyperledger Fabric] Hybrid discovery service #network #hyperledger-fabric
I couldn't find any data regarding this, but is there a way or is it in the roadmap to have a hybrid discovery service?
What I mean by hybrid is; having multiple peers on the same network, some with couchdb and some with leveldb, in a way that we can query only the peers with couchdb when we have a rich query or just query the leveldb peers, when we only query by key.