Description

Operations performed within the packet processor involve the database, should be separated into a trait.
Such trait can then be implemented multiple times, such that it represents a composable model:

• DB access base implementation
• composable caching implementation as a middleware

e.g.

trait PacketDbOps { ... }

struct PacketDbOpsImpl { ... }

impl PacketDbOps for PacketDbOpsImpl { ... }

struct CachingDbOps<Inner: PacketDbOps> {...}

impl<Inner: PacketDbOps> PacketDbOps for CachingDbOps<Inner> { ... }

Relevant issues

• Make PeerId <-> Address resolution use a cache #6045
• Remove db access in packet processing when reading channel information #6051
• Cache remaining database read operations in packet processing

Refs #5891
Refs #6031

Definition of DONE

• All DB read operations in packet processing are using a cache
• All DB write operations in packet processing cause cache invalidation