Support multiple relays for fetching content

nostr.ts

@@ -1,4 +1,4 @@
-import { NRelay1 } from "@nostrify/nostrify";
+import { NPool, NRelay1 } from "@nostrify/nostrify";
 import config from "./config.ts";
 
 export interface NEvent {
@@ -11,13 +11,18 @@ export interface NEvent {
   tags: Array<[string, string, string?]>;
 }
 
-export const relay = new NRelay1(config.home_relay_url);
+const relayPool = new NPool({
+  open: (url) => new NRelay1(url),
+  reqRouter: async (filters) => new Map(
+    config.relay_urls.map(url => [ url, filters ])
+  )
+});
 
 export async function fetchReplaceableEvent(
   pubkey: string,
   identifier: string,
 ) {
-  let events = await relay.query([{
+  let events = await relayPool.query([{
     authors: [pubkey],
     kinds: [30023],
     "#d": [identifier],
@@ -27,7 +32,7 @@ export async function fetchReplaceableEvent(
   if (events.length > 0) {
     return events[0];
   } else {
-    events = await relay.query([{
+    events = await relayPool.query([{
       authors: [pubkey],
       kinds: [30024],
       "#d": [identifier],
@@ -39,7 +44,7 @@ export async function fetchReplaceableEvent(
 }
 
 export async function fetchArticlesByAuthor(pubkey: string) {
-  const events = await relay.query([{
+  const events = await relayPool.query([{
     authors: [pubkey],
     kinds: [30023],
     limit: 10,
@@ -49,7 +54,7 @@ export async function fetchArticlesByAuthor(pubkey: string) {
 }
 
 export async function fetchProfileEvent(pubkey: string) {
-  const events = await relay.query([{
+  const events = await relayPool.query([{
     authors: [pubkey],
     kinds: [0],
     limit: 1,