FullMeshStrategy

Purpose

Every peer connects to every other peer up to a configurable cap. This is the default topology and matches the assumption baked into the drive-webrtc plugin: small (< 32) groups that benefit from direct peer-to-peer chunk transfers without a central relay. When capacity is reached, the strategy evicts the lowest-scoring existing peer if and only if the newcomer's score is strictly higher, preventing oscillation.

Features

Symmetric connect: selectConnections returns [newPeer] for every new peer below maxPeers.
Score-gated eviction: never evicts unless a strictly better peer arrives.
Self-peer never gets admitted to its own peer set.

Usage: Basic Example

import { FullMeshStrategy } from "@suaveplan/drive-webrtc";

const strategy = new FullMeshStrategy();
const decision = strategy.admitOrEvict([], newPeer, {
    maxPeers: 10,
    selfPeerId: "alice",
});

Usage: Advanced Example

import {
    FullMeshStrategy,
    PeerBandwidthTracker,
} from "@suaveplan/drive-webrtc";

const tracker = new PeerBandwidthTracker();
const strategy = new FullMeshStrategy();
const decision = strategy.admitOrEvict(currentPeers, newPeer, {
    maxPeers: 4,
    selfPeerId: "alice",
    metricsFor: (id) => tracker.get(id),
});
if (decision.admit && decision.evict !== undefined) {
    // PeerManager will evict `decision.evict` then admit `newPeer`.
}

API Reference

`new FullMeshStrategy()`

No constructor parameters.

`selectConnections(current, newPeer, options)`

Returns [newPeer] while current.length < options.maxPeers and newPeer.id !== options.selfPeerId. Empty otherwise.

`admitOrEvict(current, newPeer, options)`

Refuses duplicates (peer already in current).
Below capacity → admit with no eviction.
At capacity → find lowest-score existing peer; admit only if the newcomer's score is strictly higher.

Implementation Notes

New peers default to score 1 (treated as healthy until a sample exists), and existing peers without metrics default to 0.5. This biases admission toward fresh peers — desirable when scoring data is sparse.
The strategy never returns evict unless admit === true. The PeerManager does not need to handle a "kick this peer out anyway" decision.

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