PublishTransaction

PublishTransaction attempts to publish the passed transaction to the network. Once this returns without an error, the wallet will continually attempt to re-broadcast the transaction on start up, until it enters the chain.

Source: walletrpc/walletkit.proto

gRPC

rpc PublishTransaction (Transaction) returns (PublishResponse);

REST

HTTP Method	Path
POST	/v2/wallet/tx

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 = {
  tx_hex: <bytes>,
  label: <string>,
};
client.publishTransaction(request, function(err, response) {
  console.log(response);
});
// Console output:
//  {
//    "publish_error": <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.Transaction(
  tx_hex=<bytes>,
  label=<string>,
)
response = stub.PublishTransaction(request)
print(response)
# {
#    "publish_error": <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 = {
  tx_hex: <string>, // <bytes> (base64 encoded)
  label: <string>, // <string> 
};
let options = {
  url: `https://${REST_HOST}/v2/wallet/tx`,
  // 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:
//  {
//    "publish_error": <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/tx'
macaroon = codecs.encode(open(MACAROON_PATH, 'rb').read(), 'hex')
headers = {'Grpc-Metadata-macaroon': macaroon}
data = {
  'tx_hex': base64.b64encode(<bytes>),
  'label': <string>,
}
r = requests.post(url, headers=headers, data=json.dumps(data), verify=TLS_PATH)
print(r.json())
# {
#    "publish_error": <string>,
# }

Shell

$ lncli wallet publishtx --help

NAME:
   lncli wallet publishtx - Attempts to publish the passed transaction to the network.

USAGE:
   lncli wallet publishtx [command options] tx_hex

DESCRIPTION:
   
  Publish a hex-encoded raw transaction to the on-chain network. The 
  wallet will continually attempt to re-broadcast the transaction on start up, until it 
  enters the chain. The label parameter is optional and limited to 500 characters. Note 
  that multi word labels must be contained in quotation marks ("").
  

OPTIONS:
   --label value  (optional) transaction label
   

Messages

walletrpc.Transaction

Source: walletrpc/walletkit.proto

Field	gRPC Type	REST Type	REST Placement
tx_hex The raw serialized transaction. Despite the field name, this does need to be specified in raw bytes (or base64 encoded when using REST) and not in hex. To not break existing software, the field can't simply be renamed.	bytes	string	body
label An optional label to save with the transaction. Limited to 500 characters.	string	string	body

walletrpc.PublishResponse

Source: walletrpc/walletkit.proto

Field	gRPC Type	REST Type
publish_error If blank, then no error occurred and the transaction was successfully published. If not the empty string, then a string representation of the broadcast error. TODO(roasbeef): map to a proper enum type	string	string