aitd-address-codec

Functions for encoding and decoding AITD Ledger addresses and seeds.

Also includes support for encoding/decoding aitdd validator (node) public keys.

X-address Conversion

All tools and apps in the AITD Ledger ecosystem are encouraged to adopt support for the X-address format. The X-address format is a single Base58 string that encodes an 'Account ID', a (destination) tag, and whether the address is intended for a test network. This prevents users from unintentionally omitting the destination tag when sending and receiving payments and other transactions.

API

classicAddressToXAddress(classicAddress: string, tag: number | false, test: boolean): string

Convert a classic address and (optional) tag to an X-address. If tag is false, the returned X-address explicitly indicates that the recipient does not want a tag to be used. If test is true, consumers of the address will know that the address is intended for use on test network(s) and the address will start with T.

> const api = require('aitd-address-codec')
> api.classicAddressToXAddress('rGWrZyQqhTp9Xu7G5Pkayo7bXjH4k4QYpf', 4294967295)
'XVLhHMPHU98es4dbozjVtdWzVrDjtV18pX8yuPT7y4xaEHi'

Encode a test address e.g. for use with Testnet or Devnet:

> const api = require('aitd-address-codec')
> api.classicAddressToXAddress('r3SVzk8ApofDJuVBPKdmbbLjWGCCXpBQ2g', 123, true)
'T7oKJ3q7s94kDH6tpkBowhetT1JKfcfdSCmAXbS75iATyLD'

xAddressToClassicAddress(xAddress: string): {classicAddress: string, tag: number | false, test: boolean}

Convert an X-address to a classic address and tag. If the X-address did not have a tag, the returned object's tag will be false. (Since 0 is a valid tag, instead of if (tag), use if (tag !== false) if you want to check for a tag.) If the X-address is intended for use on test network(s), test will be true; if it is intended for use on the main network (mainnet), test will be false.

> const api = require('aitd-address-codec')
> api.xAddressToClassicAddress('XVLhHMPHU98es4dbozjVtdWzVrDjtV18pX8yuPT7y4xaEHi')
{
  classicAddress: 'rGWrZyQqhTp9Xu7G5Pkayo7bXjH4k4QYpf',
  tag: 4294967295,
  test: false
}

isValidXAddress(xAddress: string): boolean

Returns true if the provided X-address is valid, or false otherwise.

> const api = require('aitd-address-codec')
> api.isValidXAddress('XVLhHMPHU98es4dbozjVtdWzVrDjtV18pX8yuPT7y4xaEHi')
true

Returns false for classic addresses (starting with r). To validate a classic address, use isValidClassicAddress.

isValidClassicAddress(address: string): boolean

Check whether a classic address (starting with r...) is valid.

Returns false for X-addresses (extended addresses). To validate an X-address, use isValidXAddress.

encodeSeed(entropy: Buffer, type: 'ed25519' | 'secp256k1'): string

Encode the given entropy as an AITD Ledger seed (secret). The entropy must be exactly 16 bytes (128 bits). The encoding includes which elliptic curve digital signature algorithm (ECDSA) the seed is intended to be used with. The seed is used to produce the private key.

decodeSeed(seed: string): object

Decode a seed into an object with its version, type, and bytes.

Return object type:

{
  version: number[],
  bytes: Buffer,
  type: string | null
}

encodeAccountID(bytes: Buffer): string

Encode bytes as a classic address (starting with r...).

decodeAccountID(accountId: string): Buffer

Decode a classic address (starting with r...) to its raw bytes.

encodeNodePublic(bytes: Buffer): string

Encode bytes to the AITD Ledger "node public key" format (base58).

This is useful for aitdd validators.

decodeNodePublic(base58string: string): Buffer

Decode an AITD Ledger "node public key" (in base58 format) into its raw bytes.

encodeAccountPublic(bytes: Buffer): string

Encode a public key, as for payment channels.

decodeAccountPublic(base58string: string): Buffer

Decode a public key, as for payment channels.

encodeXAddress(accountId: Buffer, tag: number | false, test: boolean): string

Encode account ID, tag, and network ID to X-address.

accountId must be 20 bytes because it is a RIPEMD160 hash, which is 160 bits (160 bits = 20 bytes).

At this time, tag must be <= MAX_32_BIT_UNSIGNED_INT (4294967295) as the AITD Ledger only supports 32-bit tags.

If test is true, this address is intended for use with a test network such as Testnet or Devnet.

decodeXAddress(xAddress: string): {accountId: Buffer, tag: number | false, test: boolean}

Convert an X-address to its classic address, tag, and network ID.

Other functions

> var api = require('aitd-address-codec');
> api.decodeSeed('sEdTM1uX8pu2do5XvTnutH6HsouMaM2')
{ version: [ 1, 225, 75 ],
  bytes: [ 76, 58, 29, 33, 63, 189, 251, 20, 199, 194, 141, 96, 148, 105, 179, 65 ],
  type: 'ed25519' }
> api.decodeSeed('sn259rEFXrQrWyx3Q7XneWcwV6dfL')
{ version: 33,
  bytes: [ 207, 45, 227, 120, 251, 221, 126, 46, 232, 125, 72, 109, 251, 90, 123, 255 ],
  type: 'secp256k1' }
> api.decodeAccountID('rJrRMgiRgrU6hDF4pgu5DXQdWyPbY35ErN')
[ 186,
  142,
  120,
  98,
  110,
  228,
  44,
  65,
  180,
  109,
  70,
  195,
  4,
  141,
  243,
  161,
  195,
  200,
  112,
  114 ]

Tests

Run unit tests with:

yarn test

Use --watch to run in watch mode, so that when you modify the tests, they are automatically re-run:

yarn test --watch

Use --coverage to generate and display code coverage information:

yarn test --coverage

This tells jest to output code coverage info in the ./coverage directory, in addition to showing it on the command line.

Acknowledgements

This library references and adopts code and standards from the following sources:

• XLS-5d Standard for Tagged Addresses by @nbougalis
• AITDL Tagged Address Codec by @WietseWind
• X-Address transaction functions by @codetsunami