problem: we are querying zap providers too often

src/components/ProductPurchases.svelte

@@ -72,7 +72,7 @@
 					}
 				})
 				.catch((e) => {
-					if (e.pubkey && $currentUser && e.pubkey == $currentUser.pubkey) {
+					if (e && e.pubkey && $currentUser && e.pubkey == $currentUser.pubkey) {
 						alert(
 							'Nostrocket could not validate that the zap receipts published on your behalf are legitimate, this usually means we could not query your lightning service provider API. Consider switching to a lightning service provider that is known to work (e.g. getAlby).'
 						);

src/lib/event_helpers/rockets.ts

@@ -6,6 +6,8 @@ import { sha256 } from 'js-sha256';
 import { MapOfVotes, MeritRequest, Votes } from './merits';
 import * as immutable from 'immutable';
 import { BloomFilter } from 'bloomfilter';
+import { zappers } from '@/stores/zappers';
+import { get } from 'svelte/store';
 
 export class Rocket {
 	Event: NDKEvent;
@@ -739,20 +741,24 @@ export function RocketATagFilter(rocket: NDKEvent): string {
 
 export async function ValidateZapPublisher(rocket: NDKEvent, zap: NDKEvent): Promise<boolean> {
 	return new Promise((resolve, reject) => {
-		getAuthorizedZapper(rocket)
-			.then((pubkey) => {
-				if (pubkey == zap.pubkey) {
-					resolve(true);
-				} else {
-					reject();
-				}
-			})
-			.catch((e) => reject(e));
-		// let z = new NDKZap({ ndk: rocket.ndk!, zappedEvent: rocket, zappedUser: rocket.author });
-		// z.getZapEndpoint().then(x=>{
-		// 	console.log(x)
-		// 	resolve(true)
-		// }).catch(()=>{reject(false)})
+		let zapper = get(zappers).get(rocket.pubkey);
+		if (zapper && zapper == zap.pubkey) {
+			resolve(true);
+		} else {
+			getAuthorizedZapper(rocket)
+				.then((pubkey) => {
+					if (pubkey == zap.pubkey) {
+						zappers.update((existing) => {
+							existing.set(rocket.pubkey, pubkey);
+							return existing;
+						});
+						resolve(true);
+					} else {
+						reject();
+					}
+				})
+				.catch((e) => reject(e));
+		}
 	});
 }
 

src/lib/helpers.ts

@@ -163,7 +163,6 @@ export async function getAuthorizedZapper(rocket: NDKEvent): Promise<string> {
 		z.getZapEndpoint()
 			.then((url) => {
 				if (url) {
-					console.log(url);
 					url = url.trim().replace('/callback', '');
 					fetch(url).then((result) => {
 						result

src/lib/stores/zappers.ts

@@ -0,0 +1,3 @@
+import { writable } from 'svelte/store';
+
+export let zappers = writable(new Map<string, string>());