SendOutputs

SendOutputs is similar to the existing sendmany call in Bitcoind, and allows the caller to create a transaction that sends to several outputs at once. This is ideal when wanting to batch create a set of transactions.

Source: walletrpc/walletkit.proto

gRPC

rpc SendOutputs (SendOutputsRequest) returns (SendOutputsResponse);

REST

HTTP Method	Path
POST	/v2/wallet/send

Code Samples

gRPC

Javascript

const fs = require('fs');
const grpc = require('@grpc/grpc-js');
const protoLoader = require('@grpc/proto-loader');

const GRPC_HOST = 'localhost:10009'
const MACAROON_PATH = 'LND_DIR/data/chain/bitcoin/regtest/admin.macaroon'
const TLS_PATH = 'LND_DIR/tls.cert'

const loaderOptions = {
  keepCase: true,
  longs: String,
  enums: String,
  defaults: true,
  oneofs: true,
};
const packageDefinition = protoLoader.loadSync(['lightning.proto', 'walletrpc/walletkit.proto'], loaderOptions);
const walletrpc = grpc.loadPackageDefinition(packageDefinition).walletrpc;
process.env.GRPC_SSL_CIPHER_SUITES = 'HIGH+ECDSA';
const tlsCert = fs.readFileSync(TLS_PATH);
const sslCreds = grpc.credentials.createSsl(tlsCert);
const macaroon = fs.readFileSync(MACAROON_PATH).toString('hex');
const macaroonCreds = grpc.credentials.createFromMetadataGenerator(function(args, callback) {
  let metadata = new grpc.Metadata();
  metadata.add('macaroon', macaroon);
  callback(null, metadata);
});
let creds = grpc.credentials.combineChannelCredentials(sslCreds, macaroonCreds);
let client = new walletrpc.WalletKit(GRPC_HOST, creds);
let request = {
  sat_per_kw: <int64>,
  outputs: <TxOut>,
  label: <string>,
  min_confs: <int32>,
  spend_unconfirmed: <bool>,
};
client.sendOutputs(request, function(err, response) {
  console.log(response);
});
// Console output:
//  {
//    "raw_tx": <bytes>,
//  }

Python

import codecs, grpc, os
# Generate the following 2 modules by compiling the walletrpc/walletkit.proto with the grpcio-tools.
# See https://github.com/lightningnetwork/lnd/blob/master/docs/grpc/python.md for instructions.
import walletkit_pb2 as walletrpc, walletkit_pb2_grpc as walletkitstub

GRPC_HOST = 'localhost:10009'
MACAROON_PATH = 'LND_DIR/data/chain/bitcoin/regtest/admin.macaroon'
TLS_PATH = 'LND_DIR/tls.cert'

# create macaroon credentials
macaroon = codecs.encode(open(MACAROON_PATH, 'rb').read(), 'hex')
def metadata_callback(context, callback):
  callback([('macaroon', macaroon)], None)
auth_creds = grpc.metadata_call_credentials(metadata_callback)
# create SSL credentials
os.environ['GRPC_SSL_CIPHER_SUITES'] = 'HIGH+ECDSA'
cert = open(TLS_PATH, 'rb').read()
ssl_creds = grpc.ssl_channel_credentials(cert)
# combine macaroon and SSL credentials
combined_creds = grpc.composite_channel_credentials(ssl_creds, auth_creds)
# make the request
channel = grpc.secure_channel(GRPC_HOST, combined_creds)
stub = walletkitstub.WalletKitStub(channel)
request = walletrpc.SendOutputsRequest(
  sat_per_kw=<int64>,
  outputs=<TxOut>,
  label=<string>,
  min_confs=<int32>,
  spend_unconfirmed=<bool>,
)
response = stub.SendOutputs(request)
print(response)
# {
#    "raw_tx": <bytes>,
# }

REST

Javascript

const fs = require('fs');
const request = require('request');

const REST_HOST = 'localhost:8080'
const MACAROON_PATH = 'LND_DIR/data/chain/bitcoin/regtest/admin.macaroon'

let requestBody = {
  sat_per_kw: <string>, // <int64> 
  outputs: <array>, // <TxOut> 
  label: <string>, // <string> 
  min_confs: <integer>, // <int32> 
  spend_unconfirmed: <boolean>, // <bool> 
};
let options = {
  url: `https://${REST_HOST}/v2/wallet/send`,
  // Work-around for self-signed certificates.
  rejectUnauthorized: false,
  json: true,
  headers: {
    'Grpc-Metadata-macaroon': fs.readFileSync(MACAROON_PATH).toString('hex'),
  },
  form: JSON.stringify(requestBody),
}
request.post(options, function(error, response, body) {
  console.log(body);
});
// Console output:
//  {
//    "raw_tx": <string>, // <bytes> 
//  }

Python

import base64, codecs, json, requests

REST_HOST = 'localhost:8080'
MACAROON_PATH = 'LND_DIR/data/chain/bitcoin/regtest/admin.macaroon'
TLS_PATH = 'LND_DIR/tls.cert'

url = f'https://{REST_HOST}/v2/wallet/send'
macaroon = codecs.encode(open(MACAROON_PATH, 'rb').read(), 'hex')
headers = {'Grpc-Metadata-macaroon': macaroon}
data = {
  'sat_per_kw': <int64>,
  'outputs': <TxOut>,
  'label': <string>,
  'min_confs': <int32>,
  'spend_unconfirmed': <bool>,
}
r = requests.post(url, headers=headers, data=json.dumps(data), verify=TLS_PATH)
print(r.json())
# {
#    "raw_tx": <bytes>,
# }

Shell

# There is no CLI command for this RPC

Messages

walletrpc.SendOutputsRequest

Source: walletrpc/walletkit.proto

Field	gRPC Type	REST Type	REST Placement
sat_per_kw The number of satoshis per kilo weight that should be used when crafting this transaction.	int64	string	body
outputs A slice of the outputs that should be created in the transaction produced.	TxOut[]	array	body
label An optional label for the transaction, limited to 500 characters.	string	string	body
min_confs The minimum number of confirmations each one of your outputs used for the transaction must satisfy.	int32	integer	body
spend_unconfirmed Whether unconfirmed outputs should be used as inputs for the transaction.	bool	boolean	body

walletrpc.SendOutputsResponse

Source: walletrpc/walletkit.proto

Field	gRPC Type	REST Type
raw_tx The serialized transaction sent out on the network.	bytes	string

Nested Messages

signrpc.TxOut

Field	gRPC Type	REST Type
value The value of the output being spent.	int64	string
pk_script The script of the output being spent.	bytes	string