GetNodeMetrics

GetNodeMetrics returns node metrics calculated from the graph. Currently the only supported metric is betweenness centrality of individual nodes.

Source: lightning.proto

gRPC

rpc GetNodeMetrics (NodeMetricsRequest) returns (NodeMetricsResponse);

REST

HTTP Method	Path
GET	/v1/graph/nodemetrics

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 = {
  types: <NodeMetricType>,
};
client.getNodeMetrics(request, function(err, response) {
  console.log(response);
});
// Console output:
//  {
//    "betweenness_centrality": <BetweennessCentralityEntry>,
//  }

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.NodeMetricsRequest(
  types=<NodeMetricType>,
)
response = stub.GetNodeMetrics(request)
print(response)
# {
#    "betweenness_centrality": <BetweennessCentralityEntry>,
# }

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/graph/nodemetrics`,
  // 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:
//  {
//    "betweenness_centrality": <object>, // <BetweennessCentralityEntry> 
//  }

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/graph/nodemetrics'
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())
# {
#    "betweenness_centrality": <BetweennessCentralityEntry>,
# }

Shell

$ lncli getnodemetrics --help

NAME:
   lncli getnodemetrics - Get node metrics.

USAGE:
   lncli getnodemetrics [arguments...]

CATEGORY:
   Graph

DESCRIPTION:
   Prints out node metrics calculated from the current graph

Messages

lnrpc.NodeMetricsRequest

Source: lightning.proto

Field	gRPC Type	REST Type	REST Placement
types The requested node metrics. Nested REST Parameters types: array in query	NodeMetricType[]	object	query

lnrpc.NodeMetricsResponse

Source: lightning.proto

Field	gRPC Type	REST Type
betweenness_centrality Betweenness centrality is the sum of the ratio of shortest paths that pass through the node for each pair of nodes in the graph (not counting paths starting or ending at this node). Map of node pubkey to betweenness centrality of the node. Normalized values are in the [0,1] closed interval.	BetweennessCentralityEntry[]	object

Nested Messages

lnrpc.NodeMetricsResponse.BetweennessCentralityEntry

Field	gRPC Type	REST Type
key	string	unknown
value	FloatMetric	unknown

lnrpc.FloatMetric

Field	gRPC Type	REST Type
value Arbitrary float value.	double	number
normalized_value The value normalized to [0,1] or [-1,1].	double	number

Enums

lnrpc.NodeMetricType

Name	Number
UNKNOWN	0
BETWEENNESS_CENTRALITY	1