LookupHtlcResolution

LookupHtlcResolution retrieves a final htlc resolution from the database. If the htlc has no final resolution yet, a NotFound grpc status code is returned.

Source: lightning.proto

gRPC

rpc LookupHtlcResolution (LookupHtlcResolutionRequest) returns (LookupHtlcResolutionResponse);

REST

HTTP Method	Path
GET	/v1/htlc-resolution/{chan_id}/{htlc_index}

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', loaderOptions);
const lnrpc = grpc.loadPackageDefinition(packageDefinition).lnrpc;
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 lnrpc.Lightning(GRPC_HOST, creds);
let request = {
  chan_id: <uint64>,
  htlc_index: <uint64>,
};
client.lookupHtlcResolution(request, function(err, response) {
  console.log(response);
});
// Console output:
//  {
//    "settled": <bool>,
//    "offchain": <bool>,
//  }

Python

import codecs, grpc, os
# Generate the following 2 modules by compiling the lightning.proto with the grpcio-tools.
# See https://github.com/lightningnetwork/lnd/blob/master/docs/grpc/python.md for instructions.
import lightning_pb2 as lnrpc, lightning_pb2_grpc as lightningstub

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 = lightningstub.LightningStub(channel)
request = lnrpc.LookupHtlcResolutionRequest(
  chan_id=<uint64>,
  htlc_index=<uint64>,
)
response = stub.LookupHtlcResolution(request)
print(response)
# {
#    "settled": <bool>,
#    "offchain": <bool>,
# }

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 options = {
  url: `https://${REST_HOST}/v1/htlc-resolution/{chan_id}/{htlc_index}`,
  // Work-around for self-signed certificates.
  rejectUnauthorized: false,
  json: true,
  headers: {
    'Grpc-Metadata-macaroon': fs.readFileSync(MACAROON_PATH).toString('hex'),
  },
}
request.get(options, function(error, response, body) {
  console.log(body);
});
// Console output:
//  {
//    "settled": <boolean>, // <bool> 
//    "offchain": <boolean>, // <bool> 
//  }

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}/v1/htlc-resolution/{chan_id}/{htlc_index}'
macaroon = codecs.encode(open(MACAROON_PATH, 'rb').read(), 'hex')
headers = {'Grpc-Metadata-macaroon': macaroon}
r = requests.get(url, headers=headers, verify=TLS_PATH)
print(r.json())
# {
#    "settled": <bool>,
#    "offchain": <bool>,
# }

Shell

# There is no CLI command for this RPC

Messages

lnrpc.LookupHtlcResolutionRequest

Source: lightning.proto

Field	gRPC Type	REST Type	REST Placement
chan_id	uint64	string	path
htlc_index	uint64	string	path

lnrpc.LookupHtlcResolutionResponse

Source: lightning.proto

Field	gRPC Type	REST Type
settled Settled is true is the htlc was settled. If false, the htlc was failed.	bool	boolean
offchain Offchain indicates whether the htlc was resolved off-chain or on-chain.	bool	boolean