ReleaseOutput

ReleaseOutput unlocks an output, allowing it to be available for coin selection if it remains unspent. The ID should match the one used to originally lock the output.

Source: walletrpc/walletkit.proto

gRPC

rpc ReleaseOutput (ReleaseOutputRequest) returns (ReleaseOutputResponse);

REST

HTTP Method	Path
POST	/v2/wallet/utxos/release

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 = {
  id: <bytes>,
  outpoint: <OutPoint>,
};
client.releaseOutput(request, function(err, response) {
  console.log(response);
});
// Console output:
//  {
//    "status": <string>,
//  }

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.ReleaseOutputRequest(
  id=<bytes>,
  outpoint=<OutPoint>,
)
response = stub.ReleaseOutput(request)
print(response)
# {
#    "status": <string>,
# }

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 = {
  id: <string>, // <bytes> (base64 encoded)
  outpoint: <object>, // <OutPoint> 
};
let options = {
  url: `https://${REST_HOST}/v2/wallet/utxos/release`,
  // 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:
//  {
//    "status": <string>, // <string> 
//  }

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/utxos/release'
macaroon = codecs.encode(open(MACAROON_PATH, 'rb').read(), 'hex')
headers = {'Grpc-Metadata-macaroon': macaroon}
data = {
  'id': base64.b64encode(<bytes>),
  'outpoint': <OutPoint>,
}
r = requests.post(url, headers=headers, data=json.dumps(data), verify=TLS_PATH)
print(r.json())
# {
#    "status": <string>,
# }

Shell

$ lncli wallet releaseoutput --help

NAME:
   lncli wallet releaseoutput - Release an output previously locked by lnd.

USAGE:
   lncli wallet releaseoutput [command options] outpoint

DESCRIPTION:
   
  The releaseoutput command unlocks an output, allowing it to be available
  for coin selection if it remains unspent.

  If no lock ID is specified, the internal lnd app lock ID is used when
  releasing the output. With the internal ID, only UTXOs locked by the
  fundpsbt command can be released.
  

OPTIONS:
   --outpoint value  the output to unlock
   --lockid value    the hex-encoded app lock ID
   

Messages

walletrpc.ReleaseOutputRequest

Source: walletrpc/walletkit.proto

Field	gRPC Type	REST Type	REST Placement
id The unique ID that was used to lock the output.	bytes	string	body
outpoint The identifying outpoint of the output being released.	OutPoint	object	body

walletrpc.ReleaseOutputResponse

Source: walletrpc/walletkit.proto

Field	gRPC Type	REST Type
status The status of the release operation.	string	string

Nested Messages

lnrpc.OutPoint

Field	gRPC Type	REST Type
txid_bytes Raw bytes representing the transaction id.	bytes	string
txid_str Reversed, hex-encoded string representing the transaction id.	string	string
output_index The index of the output on the transaction.	uint32	integer