Constant LOCAL_HOST_STRS

pub const LOCAL_HOST_STRS: [&str; 2];

The main interface for interacting with the hostlist. Contains the following:

Hosts: the main parent class that manages HostRegistry and HostContainer. It is also responsible for filtering addresses before writing to the hostlist.

HostRegistry: A locked HashMap that maps peer addresses onto mutually exclusive states (HostState). Prevents race conditions by dictating a strict flow of logically acceptable states.

HostContainer: A wrapper for the hostlists. Each hostlist is represented by a HostColor, which can be Grey, White, Gold or Black. Exposes a common interface for hostlist queries and utilities.

HostColor: White: Hosts that have passed the GreylistRefinery successfully.

Gold: Hosts we have been able to establish a connection to in `OutboundSession`.

Grey: Recently received hosts that are checked by the `GreylistRefinery` and
      upgraded to the whitelist if valid. If they're inaccessible by the Refinery
      they will be deleted.

Black: hostile hosts that are strictly avoided for the duration of the program.

Dark: hosts that do not match our transports, but that we continue to share with
      other peers. We do not keep darklist entries that are older than one day.
      This is to avoid peers propagating nodes that may be faulty. We assume that
      within the one day period, the nodes will be picked up by peers that accept
      the transports and can refine them to remove inactive peers. Dark list hosts
      are otherwise ignored.

HostState: a set of mutually exclusive states that can be Insert, Refine, Connect, Suspend or Connected. The state is None when the corresponding host has been removed from the HostRegistry.

TODO: Use HostState::Free age variable to implement a pruning logic that deletes peers from the registry once they have bypassed a certain age threshold.