[lightning] start integrating features bits in the node page

backend/src/api/explorer/nodes.api.ts

@@ -3,6 +3,7 @@ import DB from '../../database';
 import { ResultSetHeader } from 'mysql2';
 import { ILightningApi } from '../lightning/lightning-api.interface';
 import { ITopNodesPerCapacity, ITopNodesPerChannels } from '../../mempool.interfaces';
+import { bin2hex } from '../../utils/format';
 
 class NodesApi {
   public async $getWorldNodes(): Promise<any> {
@@ -76,8 +77,18 @@ class NodesApi {
       node.subdivision = JSON.parse(node.subdivision);
       node.city = JSON.parse(node.city);
       node.country = JSON.parse(node.country);
-      
+
+      // Features      
       node.features = JSON.parse(node.features);
+      let maxBit = 0;
+      for (const feature of node.features) {
+        maxBit = Math.max(maxBit, feature.bit);
+      }
+      node.featuresBits = new Array(maxBit + 1).fill(0);
+      for (const feature of node.features) {
+        node.featuresBits[feature.bit] = 1;
+      }
+      node.featuresBits = bin2hex(node.featuresBits.reverse().join(''));
 
       // Active channels and capacity
       const activeChannelsStats: any = await this.$getActiveChannelsStats(public_key);

backend/src/api/lightning/clightning/clightning-convert.ts

@@ -6,7 +6,7 @@ import { hex2bin } from '../../../utils/format';
 import config from '../../../config';
 
 // https://github.com/lightningnetwork/lnd/blob/master/lnwire/features.go
-enum FeatureBits {
+export enum FeatureBits {
 	DataLossProtectRequired = 0,
 	DataLossProtectOptional = 1,
 	InitialRoutingSync = 3,
@@ -47,10 +47,7 @@ enum FeatureBits {
 	MaxBolt11Feature = 5114,
 };
   
-// Features is a mapping of known feature bits to a descriptive name. All known
-// feature bits must be assigned a name in this mapping, and feature bit pairs
-// must be assigned together for correct behavior.
-const FeaturesMap = new Map<FeatureBits, string>([
+export const FeaturesMap = new Map<FeatureBits, string>([
 	[FeatureBits.DataLossProtectRequired, 'data-loss-protect'],
 	[FeatureBits.DataLossProtectOptional, 'data-loss-protect'],
 	[FeatureBits.InitialRoutingSync, 'initial-routing-sync'],

backend/src/api/lightning/lnd/lnd-api.ts

@@ -46,10 +46,10 @@ class LndApi implements AbstractLightningApi {
 
     for (const node of graph.nodes) {
       const nodeFeatures: ILightningApi.Feature[] = [];
-      for (const bit in node.features) {
+      for (const bit in node.features) {        
         nodeFeatures.push({
           bit: parseInt(bit, 10),
-          name: node.features[bit].name,
+          name: node.features[bit].name,  
           is_required: node.features[bit].is_required,
           is_known: node.features[bit].is_known,
         });

backend/src/utils/format.ts

@@ -29,7 +29,7 @@ export function formatBytes(bytes: number, toUnit: string, skipUnit = false): st
 }
 
 // https://stackoverflow.com/a/64235212
-export function hex2bin(hex): string {
+export function hex2bin(hex: string): string {
   if (!hex) {
     return '';
   }
@@ -58,5 +58,38 @@ export function hex2bin(hex): string {
       default: return '';
     }
   }
+  return out;
+}
+
+export function bin2hex(bin: string): string {
+  if (!bin) {
+    return '';
+  }
+
+  let out = '';
+
+  for (let i = 0; i < bin.length; i += 4) {
+    const c = bin.substring(i, i + 4);
+    switch (c) {
+      case '0000': out += '0'; break;
+      case '0001': out += '1'; break;
+      case '0010': out += '2'; break;
+      case '0011': out += '3'; break;
+      case '0100': out += '4'; break;
+      case '0101': out += '5'; break;
+      case '0110': out += '6'; break;
+      case '0111': out += '7'; break;
+      case '1000': out += '8'; break;
+      case '1001': out += '9'; break;
+      case '1010': out += 'a'; break;
+      case '1011': out += 'b'; break;
+      case '1100': out += 'c'; break;
+      case '1101': out += 'd'; break;
+      case '1110': out += 'e'; break;
+      case '1111': out += 'f'; break;
+      default: return '';
+    }
+  }
+
   return out;
 }