Merge pull request #163 from getAlby/task-nwc-keysend

feat: add NWC payKeysend method

Author: rolznz

examples/nwc/keysend.js

@@ -0,0 +1,35 @@
+import * as crypto from "node:crypto"; // required in node.js
+global.crypto = crypto; // required in node.js
+import "websocket-polyfill"; // required in node.js
+
+import * as readline from "node:readline/promises";
+import { stdin as input, stdout as output } from "node:process";
+
+import { webln as providers } from "../../dist/index.module.js";
+
+const rl = readline.createInterface({ input, output });
+
+const nwcUrl =
+  process.env.NWC_URL ||
+  (await rl.question("Nostr Wallet Connect URL (nostr+walletconnect://...): "));
+const destination =
+  (await rl.question("Enter destination pubkey: ")) ||
+  "030a58b8653d32b99200a2334cfe913e51dc7d155aa0116c176657a4f1722677a3";
+const amount = await rl.question("Enter amount: ");
+rl.close();
+
+const webln = new providers.NostrWebLNProvider({
+  nostrWalletConnectUrl: nwcUrl,
+});
+await webln.enable();
+const response = await webln.keysend({
+  amount,
+  destination,
+  customRecords: {
+    696969: "1KOZHzhLs2U7JIx3BmEY",
+  },
+});
+
+console.info(response);
+
+webln.close();

examples/nwc/send-payment.js

@@ -9,20 +9,18 @@ import { webln as providers } from "../../dist/index.module.js";
 
 const rl = readline.createInterface({ input, output });
 
-const nwcUrl = await rl.question(
-  "Nostr Wallet Connect URL (nostr+walletconnect://...): ",
-);
+const nwcUrl =
+  process.env.NWC_URL ||
+  (await rl.question("Nostr Wallet Connect URL (nostr+walletconnect://...): "));
 const invoice = await rl.question("Lightning invoice: ");
 rl.close();
 
 const webln = new providers.NostrWebLNProvider({
   nostrWalletConnectUrl: nwcUrl,
 });
 await webln.enable();
-const sendPaymentResponse = await webln.sendPayment(invoice);
-console.log(sendPaymentResponse);
+const response = await webln.sendPayment(invoice);
 
-const getBalanceResponse = await webln.getBalance();
-console.log(getBalanceResponse);
+console.info(response);
 
 webln.close();

src/webln/NostrWeblnProvider.ts

@@ -58,11 +58,16 @@ type Nip47GetInfoResponse = {
   methods: string[];
 };
 
+type Nip47PayResponse = {
+  preimage: string;
+};
+
 const nip47ToWeblnRequestMap = {
   get_info: "getInfo",
   get_balance: "getBalance",
   make_invoice: "makeInvoice",
   pay_invoice: "sendPayment",
+  pay_keysend: "payKeysend",
   lookup_invoice: "lookupInvoice",
 };
 
@@ -281,7 +286,7 @@ export class NostrWebLNProvider implements WebLNProvider, Nip07Provider {
   sendPayment(invoice: string) {
     this.checkConnected();
 
-    return this.executeNip47Request<SendPaymentResponse, { preimage: string }>(
+    return this.executeNip47Request<SendPaymentResponse, Nip47PayResponse>(
       "pay_invoice",
       {
         invoice,
@@ -291,10 +296,29 @@ export class NostrWebLNProvider implements WebLNProvider, Nip07Provider {
     );
   }
 
-  // not-yet implemented WebLN interface methods
-  keysend(args: KeysendArgs): Promise<SendPaymentResponse> {
-    throw new Error("Method not implemented.");
+  keysend(args: KeysendArgs) {
+    this.checkConnected();
+
+    return this.executeNip47Request<SendPaymentResponse, Nip47PayResponse>(
+      "pay_keysend",
+      {
+        amount: +args.amount * 1000, // NIP-47 uses msat
+        pubkey: args.destination,
+        tlv_records: args.customRecords
+          ? Object.entries(args.customRecords).map((v) => ({
+              type: parseInt(v[0]),
+              value: v[1],
+            }))
+          : [],
+        // TODO: support optional preimage
+        // preimage?: "123",
+      },
+      (result) => !!result.preimage,
+      (result) => ({ preimage: result.preimage }),
+    );
   }
+
+  // not-yet implemented WebLN interface methods
   lnurl(
     lnurl: string,
   ): Promise<{ status: "OK" } | { status: "ERROR"; reason: string }> {