nip57: implement "P" tag for sender.

fixes https://github.com/nbd-wtf/nostr-tools/issues/337

README.md

@@ -66,18 +66,18 @@ const sub = relay.subscribe([
 let sk = generateSecretKey()
 let pk = getPublicKey(sk)
 
-let sub = relay.sub([
+relay.sub([
   {
     kinds: [1],
     authors: [pk],
   },
-])
-
-sub.on('event', event => {
-  console.log('got event:', event)
+], {
+  onevent(event) {
+    console.log('got event:', event)
+  }
 })
 
-let event = {
+let eventTemplate = {
   kind: 1,
   created_at: Math.floor(Date.now() / 1000),
   tags: [],
@@ -85,14 +85,9 @@ let event = {
 }
 
 // this assigns the pubkey, calculates the event id and signs the event in a single step
-const signedEvent = finalizeEvent(event, sk)
+const signedEvent = finalizeEvent(eventTemplate, sk)
 await relay.publish(signedEvent)
 
-let events = await relay.list([{ kinds: [0, 1] }])
-let event = await relay.get({
-  ids: ['44e1827635450ebb3c5a7d12c1f8e7b2b514439ac10a67eef3d9fd9c5c68e245'],
-})
-
 relay.close()
 ```
 

helpers.ts

@@ -1,10 +1,15 @@
 import { verifiedSymbol, type Event, type Nostr, VerifiedEvent } from './core.ts'
 
 export async function yieldThread() {
-  return new Promise(resolve => {
+  return new Promise<void>(resolve => {
     const ch = new MessageChannel()
+    const handler = () => {
+      // @ts-ignore (typescript thinks this property should be called `removeListener`, but in fact it's `removeEventListener`)
+      ch.port1.removeEventListener('message', handler)
+      resolve()
+    }
     // @ts-ignore (typescript thinks this property should be called `addListener`, but in fact it's `addEventListener`)
-    ch.port1.addEventListener('message', resolve)
+    ch.port1.addEventListener('message', handler)
     ch.port2.postMessage(0)
     ch.port1.start()
   })

nip57.test.ts

@@ -242,10 +242,11 @@ describe('validateZapRequest', () => {
 })
 
 describe('makeZapReceipt', () => {
-  test('returns a valid Zap receipt with a preimage', () => {
-    const privateKey = generateSecretKey()
-    const publicKey = getPublicKey(privateKey)
+  const privateKey = generateSecretKey()
+  const publicKey = getPublicKey(privateKey)
+  const target = 'efeb5d6e74ce6ffea6cae4094a9f29c26b5c56d7b44fae9f490f3410fd708c45'
 
+  test('returns a valid Zap receipt with a preimage', () => {
     const zapRequest = JSON.stringify(
       finalizeEvent(
         {
@@ -253,7 +254,7 @@ describe('makeZapReceipt', () => {
           created_at: Date.now() / 1000,
           content: 'content',
           tags: [
-            ['p', publicKey],
+            ['p', target],
             ['amount', '100'],
             ['relays', 'relay1', 'relay2'],
           ],
@@ -274,16 +275,14 @@ describe('makeZapReceipt', () => {
       expect.arrayContaining([
         ['bolt11', bolt11],
         ['description', zapRequest],
-        ['p', publicKey],
+        ['p', target],
+        ['P', publicKey],
         ['preimage', preimage],
       ]),
     )
   })
 
   test('returns a valid Zap receipt without a preimage', () => {
-    const privateKey = generateSecretKey()
-    const publicKey = getPublicKey(privateKey)
-
     const zapRequest = JSON.stringify(
       finalizeEvent(
         {
@@ -291,7 +290,7 @@ describe('makeZapReceipt', () => {
           created_at: Date.now() / 1000,
           content: 'content',
           tags: [
-            ['p', publicKey],
+            ['p', target],
             ['amount', '100'],
             ['relays', 'relay1', 'relay2'],
           ],
@@ -311,7 +310,8 @@ describe('makeZapReceipt', () => {
       expect.arrayContaining([
         ['bolt11', bolt11],
         ['description', zapRequest],
-        ['p', publicKey],
+        ['p', target],
+        ['P', publicKey],
       ]),
     )
     expect(JSON.stringify(result.tags)).not.toContain('preimage')

nip57.ts

@@ -119,7 +119,7 @@ export function makeZapReceipt({
     kind: 9735,
     created_at: Math.round(paidAt.getTime() / 1000),
     content: '',
-    tags: [...tagsFromZapRequest, ['bolt11', bolt11], ['description', zapRequest]],
+    tags: [...tagsFromZapRequest, ['P', zr.pubkey], ['bolt11', bolt11], ['description', zapRequest]],
   }
 
   if (preimage) {

package.json

@@ -1,7 +1,7 @@
 {
   "type": "module",
   "name": "nostr-tools",
-  "version": "2.1.1",
+  "version": "2.1.2",
   "description": "Tools for making a Nostr client.",
   "repository": {
     "type": "git",