protocol

tbDEX Protocol

Library that can be used to create, parse, verify, and validate the tbDEX Messages and Resources defined in the protocol specification

Table of Contents

• Installation
• Usage
  • Message Creation
  • Message Parsing
  • Message Validation
  • Integrity Check
  • Sending Requests
• Development
  • Prerequisites
    • node and npm
  • Running Tests
  • npm scripts

Installation

npm install @tbdex/protocol

Usage

Message Creation

There's a concrete class for each Message Kind. These classes can be used to create messages. e.g.

import { DevTools, Rfq } from '@tbdex/protocol'

const rfq = Rfq.create({
  metadata : { from: alice.did, to: 'did:ex:pfi' },
  data     : {
    offeringId  : 'abcd123',
    payinMethod : {
      kind           : 'DEBIT_CARD',
      paymentDetails : {
        'cardNumber'     : '1234567890123456',
        'expiryDate'     : '12/22',
        'cardHolderName' : 'Ephraim Bartholomew Winthrop',
        'cvv'            : '123'
      }
    },
    payoutMethod: {
      kind           : 'BTC_ADDRESS',
      paymentDetails : {
        btcAddress: '1A1zP1eP5QGefi2DMPTfTL5SLmv7DivfNa'
      }
    },
    payinAmount : '200.00',
    claims      : ['']
  }
})

await rfq.sign(alice)

console.log(JSON.stringify({ message: rfq }, null, 2))

Message Parsing

All messages can be parsed from json into an instance of the Message Kind's class using the parseMessage method. e.g.

import { parseMessage } from '@tbdex/protocol'

const jsonMessage = "<SERIALIZED_MESSAGE>"
const message = await parseMessage(jsonMessage)

if (message.isRfq()) {
  // rfq specific logic
}

If you know what kind of message you are expecting, you can use a message kind specific .parse() method. e.g.

import { Rfq, Quote } from '@tbdex/protocol'

const jsonRfq = "<SERIALIZED_RFQ>"
const rfq = Rfq.parse(jsonRfq)

const jsonQuote = "<SERIALIZED_QUOTE>"
const quote = Quote.parse(jsonQuote)

Parsing a message includes format validation, signature integrity checking, and other validations specific to each message kind.

Message Validation and Verification

Given an instance of a Message or Resource, you can perform validations with different levels of granularity.

• Message#verify() performs format validation, a signature integrity check, and validations specific to a each message kind. However, it does NOT perform validations that require knowledge of other messages in an exchange.
• Message#verifySignature() performs a signature integrity check.
• Message#validate() performs a format validation against the official TBDex JSON Schemas. It will fail if the message has not yet been signed.

Rfq Validation

An Rfq must also be validated against its corresponding Offering.

import { Offering, Rfq } from '@tbdex/protocol'

const offering = Offering.parse("<SERIALIZED_OFFERING>")
const rfq = Rfq.parse("<SERIALIZED_RFQ>")
await rfq.verifyOfferingRequirements(offering)