corestore-swarm-networking

A corestore networking module that uses hyperswarm to discovery peers. This module powers the networking portion of the Hyperdrive daemon.

Calls to seed or unseed will not be persisted across restarts, so you'll need to use a separate database that maps discovery keys to network configurations. The Hyperdrive daemon uses Level for this.

Since corestore has an all-to-all replication model (any shared cores between two peers will be automatically replicated), only one connection needs to be maintained per peer. If multiple connections are opened to a single peer as a result of that peer announcing many keys, then these connections will be automatically deduplicated by comparing NOISE keypairs.

Installation

npm i corestore-swarm-networking -g

Usage

const SwarmNetworker = require('corestore-swarm-networking')
const Corestore = require('corestore')
const ram = require('random-access-memory')

const store = new Corestore(ram)
await store.ready()

const networker = new SwarmNetworker(store)

// Start announcing or lookup up a discovery key on the DHT.
await networker.join(discoveryKey, { announce: true, lookup: true })

// Stop announcing or looking up a discovery key.
networker.leave(discoveryKey)

// Shut down the swarm (and unnanounce all keys)
await networker.close()

API

const networker = new SwarmNetworker(corestore, networkingOptions = {})

Creates a new SwarmNetworker that will open replication streams on the corestore instance argument.

networkOpts is an options map that can include all hyperswarm options (which will be passed to the internal swarm instance) as well as:

{
  id: crypto.randomBytes(32), // A randomly-generated peer ID,
  keyPair: HypercoreProtocol.keyPair(), // A NOISE keypair that's used across all connections.
}

await networker.join(discoveryKey, opts = {})

Join the swarm with the discoveryKey argument as the topic.

If this is the first time a join or leave has been called, the swarm instance will be created automatically.

Waits for the topic to be fully joined before resolving.

opts is an options map of network configuration options that can include:

  announce: true, // Announce the discovery key on the swarm
  lookup: true  // Look up the discovery key on the swarm

networker.joined(discoveryKey)

Returns true if that discovery key is being swarmed.

networker.flushed(discoveryKey)

Returns true if the swarm has discovered and attempted to connect to all peers announcing discoveryKey.

await networker.leave(discoveryKey)

Stop announcing or looking up the discovery key topic.

Waits for the key to be fully unannounced before resolving.

await networker.close()

Shut down the swarm networker.

This will close all replication streams and then destroy the swarm instance. It will wait for all topics to be unannounced, so it might take some time.

License

MIT