[Epic] Sharded peer management and discovery

[SionoiS]

Planned start date: 14 August
Due date: TBD

Summary

If we assume that peer discovery takes care of filtering peers by shard, these peers must be managed in a way that makes sense in a dynamic auto-sharded environment.

Acceptance Criteria

• Node can filter discovered peers according to shards subscriptions.
• Node update its own discoverable ENR every time its subscriptions changes.
• peer store must preferably try to keep at least a target n peers for each subscribed shard (note that dynamically subscribing/unsubscribing from shards could complicate this)
• peer manager must attempt to maintain a healthy relay connectivity for each subscribed shard
• a mechanism to perform ad-hoc discovery (or another solution) to cater for when a node subscribes to a shard for which there are no tracked peers

Tasks

• feat: update ENR based on RPC topic subscribe #1843
• feat(discv5): update filter predicate #1918

RAID (Risks, Assumptions, Issues and Dependencies)

[SionoiS]

Weekly Update

• achieved: discv5 ENR update & filter predicate run-time updating
• next: PRs feedback updates

[SionoiS]

Weekly Update

• achieved: topic subscriptions update discv5 ENR and filter predicate. PRs merged.

[SionoiS]

Closing as it is done.