ban-list.ts

import debugDefault from 'debug'
import { LRUCache } from 'lru-cache'

import { formatLogId } from '../util.js'

import { KBucket } from './kbucket.js'

import type { PeerInfo } from '../types.js'

const debug = debugDefault('devp2p:dpt:ban-list')
const verbose = debugDefault('verbose').enabled

export class BanList {
  private _lru: LRUCache<string, boolean>
  private DEBUG: boolean
  constructor() {
    this._lru = new LRUCache({ max: 10000 })
    this.DEBUG =
      typeof window === 'undefined' ? (process?.env?.DEBUG?.includes('ethjs') ?? false) : false
  }

  add(obj: string | Uint8Array | PeerInfo, maxAge?: number) {
    for (const key of KBucket.getKeys(obj)) {
      this._lru.set(key, true, { ttl: maxAge })
      if (this.DEBUG) {
        debug(`Added peer ${formatLogId(key, verbose)}, size: ${this._lru.size}`)
      }
    }
  }

  has(obj: string | Uint8Array | PeerInfo): boolean {
    return KBucket.getKeys(obj).some((key: string) => Boolean(this._lru.get(key)))
  }
}