Collection of helpful building blocks and tools to develop Bitcoin Lightning web apps
npm install @getalby/lightning-tools

An npm package that provides useful and common tools and helpers to build lightning web applications.
Skip the rest of this README and use the Alby Bitcoin Payments Agent Skill instead. It will handle the rest!
```
npm install @getalby/lightning-tools
or
``
yarn add @getalby/lightning-tools
or for use without any build tools:
`html`
This library relies on a global fetch() function which will work in browsers and node v18 or newer. (In older versions you have to use a polyfill.)
The LightningAddress class provides helpers to work with lightning addresses
`js
import { LightningAddress } from "@getalby/lightning-tools/lnurl";
const ln = new LightningAddress("hello@getalby.com");
// fetch the LNURL data
await ln.fetch();
// get the LNURL-pay data:
console.log(ln.lnurlpData); // returns a LNURLPayResponse
// get the keysend data:
console.log(ln.keysendData);
`
#### Get an invoice:
`js
import { LightningAddress } from "@getalby/lightning-tools/lnurl";
const ln = new LightningAddress("hello@getalby.com");
await ln.fetch();
// request an invoice for 1000 satoshis
// this returns a new Invoice class that can also be used to validate the payment
const invoice = await ln.requestInvoice({ satoshi: 1000 });
console.log(invoice.paymentRequest); // print the payment request
console.log(invoice.paymentHash); // print the payment hash
`
#### Verify a payment
`js
import { LightningAddress } from "@getalby/lightning-tools/lnurl";
const ln = new LightningAddress("hello@getalby.com");
await ln.fetch();
const invoice = await ln.requestInvoice({ satoshi: 1000 });
// if the LNURL providers supports LNURL-verify:
const paid = await invoice.verifyPayment(); // returns true of false
if (paid) {
console.log(invoice.preimage);
}
// if you have the preimage for example in a WebLN context
await window.webln.enable();
const response = await window.webln.sendPayment(invoice.paymentRequest);
const paid = invoice.validatePreimage(response.preimage); // returns true or false
if (paid) {
console.log("paid");
}
// or use the convenient method:
await invoice.isPaid();
`
It is also possible to manually initialize the Invoice
`js
import { Invoice } from "@getalby/lightning-tools/bolt11";
const invoice = new Invoice({ pr: pr, preimage: preimage });
await invoice.isPaid();
`
#### Boost a LN address:
You can also attach additional metadata information like app name, version, name of the podcast which is boosted etc. to the keysend payment.
`js
import { LightningAddress } from "@getalby/lightning-tools/lnurl";
const ln = new LightningAddress("hello@getalby.com");
await ln.fetch();
const boost = {
action: "boost",
value_msat: 21000,
value_msat_total: 21000,
app_name: "Podcastr",
app_version: "v2.1",
feedId: "21",
podcast: "random podcast",
episode: "1",
ts: 2121,
name: "Satoshi",
sender_name: "Alby",
};
await ln.boost(boost);
`
#### Zapping a LN address on Nostr:
Nostr is a simple, open protocol that enables truly censorship-resistant and global value-for-value publishing on the web. Nostr integrates deeply with Lightning. more info
This librarys provides helpers to create zaps.
`js
import { LightningAddress } from "@getalby/lightning-tools/lnurl";
const ln = new LightningAddress("hello@getalby.com");
await ln.fetch();
const response = await ln.zap({
satoshi: 1000,
comment: "Awesome post",
relays: ["wss://relay.damus.io"],
e: "44e1827635450ebb3c5a7d12c1f8e7b2b514439ac10a67eef3d9fd9c5c68e245",
});
console.log(response.preimage); // print the preimage
`
For a full example see examples/zaps
#### Zapping a LN address on Nostr using Nostr Wallet Connect:
Native zaps without a browser extension are possible by using a Nostr Wallet Connect WebLN provider.
L402 is a protocol standard based on the HTTP 402 Payment Required error code
designed to support the use case of charging for services and
authenticating users in distributed networks.
This library includes a fetchWithL402 function to consume L402 protected resources.
#### fetchWithL402(url: string, fetchArgs, options)
- url: the L402 protected URL
- fetchArgs: arguments are passed to the underlying fetch() function used to do the HTTP requestsendPayment()
- options:
- webln: the webln object used to call defaults to globalThis.weblngetItem()
- store: a key/value store object to persiste the l402 for each URL. The store must implement a /setItem() function as the browser's localStorage. By default a memory storage is used.
- headerKey: defaults to L402 but if you need to consume an old LSAT API set this to LSAT
##### Examples
`js
import { fetchWithL402 } from "@getalby/lightning-tools/l402";
// this will fetch the resource and pay the invoice with window.webln.
// the tokens/preimage data will be stored in the browser's localStorage and used for any following request
await fetchWithL402(
"https://lsat-weather-api.getalby.repl.co/kigali",
{},
{ store: window.localStorage },
)
.then((res) => res.json())
.then(console.log);
`
`js
import { fetchWithL402 } from "@getalby/lightning-tools/l402";
import { NostrWebLNProvider } from "@getalby/sdk";
// use a NWC WebLN provide to do the payments
const nwc = new NostrWebLNProvider({
nostrWalletConnectUrl: loadNWCUrl(),
});
// this will fetch the resource and pay the invoice with a NWC webln object
await fetchWithL402(
"https://lsat-weather-api.getalby.repl.co/kigali",
{},
{ webln: nwc },
)
.then((res) => res.json())
.then(console.log);
`
`js
import { fetchWithL402, NoStorage } from "@getalby/lightning-tools/l402";
// do not store the tokens
await fetchWithL402(
"https://lsat-weather-api.getalby.repl.co/kigali",
{},
{ store: new NoStorage() },
);
`
You can initialize an Invoice to decode a payment request.
`js
import { Invoice } from "@getalby/lightning-tools/bolt11";
const invoice = new Invoice({ pr });
const { paymentHash, satoshi, description, createdDate, expiryDate } = invoice;
`
> If you need more details about the invoice, use a dedicated BOLT11 decoding library.
Helpers to convert sats values to fiat and fiat values to sats.
##### getFiatCurrencies(): Promise
Returns the list of available fiat currencies sorted by priority
##### getFiatValue(satoshi: number, currency: string): number
Returns the fiat value for a specified currency of a satoshi amount
##### getSatoshiValue(amount: number, currency: string): number
Returns the satoshi value for a specified amount (in the smallest denomination) and currency
##### getFormattedFiatValue(satoshi: number, currency: string, locale: string): string
Like getFiatValue but returns a formatted string for a given locale using JavaScript's toLocaleString
#### Examples
`js`
await fiat.getFiatCurrencies();
await fiat.getFiatValue({ satoshi: 2100, currency: "eur" });
await fiat.getSatoshiValue({ amount: 100, currency: "eur" }); // for 1 EUR
await fiat.getFormattedFiatValue({
satoshi: 2100,
currency: "usd",
locale: "en",
});
This library uses a proxy to simplify requests to lightning providers.
- Many ln addresses don't support CORS, which means fetching the data directly in a browser environment will not always work.
- Two requests are required to retrieve lnurlp and keysend data for a lightning address. The proxy will do these for you with a single request.
You can disable the proxy by explicitly setting the proxy to false when initializing a lightning address:
`js`
const lightningAddress = new LightningAddress("hello@getalby.com", {
proxy: false,
});
If you get an crypto is not defined in NodeJS error you have to import it first:
`js`
import * as crypto from 'crypto'; // or 'node:crypto'
globalThis.crypto = crypto as any;
//or: global.crypto = require('crypto');
This library relies on a global fetch object which will work in browsers and node v18.x or newer. In old version you can manually install a global fetch option or polyfill if needed.
For example:
`js
import fetch from "cross-fetch"; // or "@inrupt/universal-fetch"
globalThis.fetch = fetch;
// or as a polyfill:
import "cross-fetch/polyfill";
`
```
yarn install
yarn run build
We are happy to help, please contact us or create an issue.
- Twitter: @getAlby
- Telegram group
- support at getalby.com
- bitcoin.design Discord community (find us on the #alby channel)
- Read the Alby developer guide to better understand how Alby packages and APIs can be used to power your app.
MIT