Adapter

Adapters provide a unified interface for communicating with relays. Adapters aren't meant to be used directly, but as an injection point for custom logic.

Core Classes

AbstractAdapter

Base class for all adapters. Handles events and cleanup.

• send(message) - Send message to relay
• cleanup() - Clean up resources
• Emits AdapterEvent.Receive when messages arrive

Built-in Adapters

• SocketAdapter(socket) - WebSocket relay connections
• LocalAdapter(relay) - Local in-memory relays
• MockAdapter(url, sendHandler) - Testing with manual control

Factory

getAdapter(url, context?) creates the appropriate adapter:

const adapter = getAdapter('wss://relay.example.com')
adapter.on(AdapterEvent.Receive, (message, url) => {
  console.log('Received:', message)
})
adapter.send(['REQ', 'sub1', {}])
adapter.cleanup()

Custom Adapter Example

Custom adapters can be created against any target:

class IPFSAdapter extends AbstractAdapter {
  constructor(private url string) {
    super()

    // Set up an IPFS connection here
  }

  get urls() { return [this.url] }
  get sockets() { return [] }

  send(message: ClientMessage) {
    // Handle messages as if the ipfs backend was a relay
  }
}

Custom adapters can also be provided to several net utilities, including publish and request:

request({
  relays: ['ipfs://QmTy8w65yBXgyfG2ZBg5TrfB2hPjrDQH3RCQFJGkARStJb'],
  filters: [{kinds: [1]}],
  context: {
    getAdapter: (url: string) => {
      // getAdapter optionally returns an adapter. If none is returned, the stock adapters will be used.
      if (url.startsWith('ipfs://')) {
        return new IPFSAdapter(url)
      }
    },
  },
})