persistent libp2p peerid

js-libp2p.ts

import { IDBDatastore } from 'datastore-idb'
import {
  createDelegatedRoutingV1HttpApiClient,
  DelegatedRoutingV1HttpApiClient,
} from '@helia/delegated-routing-v1-http-api-client'
import { createLibp2p, Libp2p } from 'libp2p'
import { identify } from '@libp2p/identify'
import { peerIdFromString } from '@libp2p/peer-id'
import { noise } from '@chainsafe/libp2p-noise'
import { yamux } from '@chainsafe/libp2p-yamux'
import { bootstrap } from '@libp2p/bootstrap'
import { Multiaddr } from '@multiformats/multiaddr'
import { sha256 } from 'multiformats/hashes/sha2'
import type { Message, SignedMessage, PeerId } from '@libp2p/interface'
import { gossipsub } from '@chainsafe/libp2p-gossipsub'
import { createEd25519PeerId } from '@libp2p/peer-id-factory'
import { Key } from 'interface-datastore'
import { keychain } from '@libp2p/keychain'
import { defaultLogger } from '@libp2p/logger'

import { webSockets } from '@libp2p/websockets'
import { webTransport } from '@libp2p/webtransport'
import { webRTC, webRTCDirect } from '@libp2p/webrtc'

// application-specific data lives in the datastore
const datastore = new IDBDatastore('app')
await datastore.open()

let peerId: PeerId
// Try to load peer from data store
const selfKey = new Key('/pkcs8/self')
const chain = keychain()({ datastore, logger: defaultLogger() })
if (await datastore.has(selfKey)) {
  // load the peer id from the keychain
  peerId = await chain.exportPeerId('self')
} else {
  // Create a new one and load it into the chain
  peerId = await createEd25519PeerId()
  await chain.importPeer('self', peerId)
}

const libp2p = await createLibp2p({
  peerId: peerId ?? undefined,
  datastore
})