most simple relay pool.

README.md

@@ -120,6 +120,22 @@ To use this on Node.js you first must install `websocket-polyfill` and import it
 import 'websocket-polyfill'
 ```
 
+### Interacting with multiple relays
+
+```js
+import {pool} from 'nostr-tools'
+
+const p = pool()
+
+["wss://relay.example.com", "wss://relay.example2.com"].forEach(async url => {
+  let relay = pool.ensureRelay(url)
+  await relay.connect()
+
+  relay.sub(...) // same as above
+  relay.publish(...) // etc
+})
+```
+
 ### Querying profile data from a NIP-05 address
 
 ```js
@@ -195,7 +211,7 @@ let event = {
 sendEvent(event)
 
 // on the receiver side
-sub.on('event', (event) => {
+sub.on('event', event => {
   let sender = event.tags.find(([k, v]) => k === 'p' && v && v !== '')[1]
   pk1 === sender
   let plaintext = await nip04.decrypt(sk2, pk1, event.content)

index.ts

@@ -2,6 +2,7 @@ export * from './keys'
 export * from './relay'
 export * from './event'
 export * from './filter'
+export * from './pool'
 
 export * as nip04 from './nip04'
 export * as nip05 from './nip05'

package.json

@@ -1,6 +1,6 @@
 {
   "name": "nostr-tools",
-  "version": "1.2.1",
+  "version": "1.2.3",
   "description": "Tools for making a Nostr client.",
   "repository": {
     "type": "git",

pool.ts

@@ -0,0 +1,27 @@
+import {Relay, relayInit} from './relay'
+import {normalizeURL} from './utils'
+
+export function pool(defaultRelays: string[] = []) {
+  return new SimplePool(defaultRelays)
+}
+
+class SimplePool {
+  private _conn: {[url: string]: Relay}
+  private _knownIds: Set<string> = new Set()
+
+  constructor(defaultRelays: string[]) {
+    this._conn = {}
+    defaultRelays.forEach(this.ensureRelay)
+  }
+
+  ensureRelay(url: string): Relay {
+    const nm = normalizeURL(url)
+    const existing = this._conn[nm]
+    if (existing) return existing
+
+    const hasEventId = (id: string): boolean => this._knownIds.has(id)
+    const relay = relayInit(nm, hasEventId)
+    this._conn[nm] = relay
+    return relay
+  }
+}

utils.ts

@@ -3,6 +3,20 @@ import {Event} from './event'
 export const utf8Decoder = new TextDecoder('utf-8')
 export const utf8Encoder = new TextEncoder()
 
+export function normalizeURL(url: string): string {
+  let p = new URL(url)
+  p.pathname = p.pathname.replace(/\/+/g, '/')
+  if (p.pathname.endsWith('/')) p.pathname = p.pathname.slice(0, -1)
+  if (
+    (p.port === '80' && p.protocol === 'ws:') ||
+    (p.port === '443' && p.protocol === 'wss:')
+  )
+    p.port = ''
+  p.searchParams.sort()
+  p.hash = ''
+  return p.toString()
+}
+
 //
 // fast insert-into-sorted-array functions adapted from https://github.com/terrymorse58/fast-sorted-array
 //