This library simplifies connecting to the Bitcoin Lightning Network Daemon via gRPC. It wraps all callback functions in promises to make api calls easier to work with.
This library supports LND version 0.17.0-beta.
The default behavior assumes LND is running on localhost port 10009. It also assumes that macaroons are enabled and the tls.cert and admin.macaroon are found in the OS specific default data paths.
To establish a connection to gRPC localhost:10009 with macaroons:
const lnd = require('lnd-async');
async function getInfo() {
let client = await lnd.connect();
return await client.getInfo({});
}This call can be customized to meet your specific needs:
const lnd = require('lnd-async');
async function getInfo() {
let client = await lnd.connect({
lndHost: '10.10.0.12',
lndPort: 10019,
certPath: __dirname + '/tls.cert',
macaroonPath: __dirname + '/admin.macaroon',
});
return await client.getInfo({});
}You can also specify cert and macaroon as base64 encoded string. Usefull if you do not want to keep them on the server. To do this you can do it buy commands like base64 -w 0 /path/to/lnd/data/tls.cert; echo for cert or base64 -w 0 /path/to/lnd/data/admin.macaroon; echo for macaroon.
const lnd = require('lnd-async');
async function getInfo() {
let client = await lnd.connect({
lndHost: '10.10.0.12',
lndPort: 10019,
cert: 'base64 cert',
macaroon: 'base64 macaroon',
});
return await client.getInfo({});
}You can also initiate calls with no macaroons by passing the noMacaroons flag. When this option is supplied, the macaroonPath is ignored.
const lnd = require('lnd-async');
async function getInfo() {
let client = await lnd.connect({ noMacaroons: true });
return await client.getInfo({});
}By default the lnd-async uses Lightning service but you can call certain methods of other services:
// The "Invoices" service for example:
await client.Invoices.settleInvoice({preimage})
// The default "Lightning" service:
await client.connectPeer({addr: {pubkey, host}, perm: false})
// The stream method:
const grpc = require('grpc')
let stream = client.Invoices.subscribeSingleInvoice({r_hash: hash})
stream.on('data', async data => {
try {
if (data.state === 'ACCEPTED' && accepted) {
await accepted()
}
else if (data.state === 'SETTLED' && settled) {
await settled()
stream.cancel()
}
else if (data.state === 'CANCELED' && canceled) {
await canceled()
stream.cancel()
}
}
catch (e) {
console.error('error in data event of stream: %s', e.message)
}
})
stream.on('error', (e) => {
// If e.code === grpc.status.CANCELLED - it's normal cancel state of stream
if (e.code !== grpc.status.CANCELLED) {
error(e)
}
})
The JavaScript Number type internally stores values as IEEE 754 floating point values. The max safe integer value is 2^53-1 which can result in data loss for 64-bit integers.
By default and for maximum portability, long values are returned as strings. This allows the consumer of the data to convert the long integers using any big number library they prefer.
grpc-node has accomodations for automatic number type conversion to Long.js. If you do not install Long.js, longs will be treated as JavaScript Number type and data loss may occur.
lnd-async allows customization of this handling via the setting longsAsNumbers. Setting this value to true will pass the Number setting in grpc-node. By default, this value is set to false to prevent data loss.
const lnd = require('lnd-async');
async function getInfo() {
let client = await lnd.connect({ longsAsNumbers: true });
return await client.getInfo({});
}longsAsNumbers option