@libp2p/interface-record

@libp2p/interface-record

Record interface for libp2p

Table of contents

• Install
• Usage
• Create Record
• API
  • marshal
  • equals
• License
• Contribution

Install

$ npm i @libp2p/interface-record

A libp2p node needs to store data in a public location (e.g. a DHT), or rely on potentially untrustworthy intermediaries to relay information. Libp2p provides an all-purpose data container called envelope, which includes a signature of the data, so that it its authenticity can be verified.

The record represents the data that will be stored inside the envelope when distributing records across the network. The interface-record aims to guarantee that any type of record created is compliant with the libp2p envelope.

Taking into account that a record might be used in different contexts, an envelope signature made for a specific purpose must not be considered valid for a different purpose. Accordingly, each record has a short and descriptive string representing the record use case, known as domain. The data to be signed will be prepended with the domain string, in order to create a domain signature.

A record can also contain a Uint8Array codec (ideally registered as a multicodec). This codec will prefix the record data in the envelope , so that it can be deserialized deterministically.

Usage

const tests = require('libp2p-interfaces-compliance-tests/record')
describe('your record', () => {
  tests({
    async setup () {
      return YourRecord
    },
    async teardown () {
      // cleanup resources created by setup()
    }
  })
})

Create Record

const multicodec = require('multicodec')
const Record = require('libp2p-interfaces/src/record')
const { fromString } = require('uint8arrays/from-string')
// const Protobuf = require('./record.proto')

const ENVELOPE_DOMAIN_PEER_RECORD = 'libp2p-peer-record'
const ENVELOPE_PAYLOAD_TYPE_PEER_RECORD = fromString('0301', 'hex')

/**
 * @implements {import('libp2p-interfaces/src/record/types').Record}
 */
class PeerRecord {
  constructor (peerId, multiaddrs, seqNumber) {
    this.domain = ENVELOPE_DOMAIN_PEER_RECORD
    this.codec = ENVELOPE_PAYLOAD_TYPE_PEER_RECORD
  }

  /**
   * Marshal a record to be used in an envelope.
   *
   * @returns {Uint8Array}
   */
  marshal () {
    // Implement and return using Protobuf
  }

  /**
   * Returns true if `this` record equals the `other`.
   *
   * @param {PeerRecord} other
   * @returns {other is Record}
   */
  equals (other) {
    // Verify
  }
}

API

marshal

• record.marshal()

Marshal a record to be used in a libp2p envelope.

Returns

It returns a Protobuf containing the record data.

equals

• record.equals(other)

Verifies if the other Record is identical to this one.

Parameters

• other is a Record to compare with the current instance.

Returns

• other is Record

License

Licensed under either of

• Apache 2.0, (LICENSE-APACHE / http://www.apache.org/licenses/LICENSE-2.0)
• MIT (LICENSE-MIT / http://opensource.org/licenses/MIT)

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.