archethic_lib_dart 0.0.12+12

ArchEthic dart library for Flutter based on Official ArchEthic Javascript library for Node and Browser

archethic_lib_dart

ArchEthic dart library for Flutter based on Official ArchEthic Javascript library for Node and Browser

Usage

This library aims to provide a easy way to create ArchEthic transaction and to send them over the network.

It supports the ArchEthic Cryptography rules which are:

• Algorithm identification: keys are prepared by metadata bytes to indicate the curve used and the origin of the generation, and hashes are prepended by a byte to indicate the hash algorithm used. Those information help during the verification

  
      Ed25519   Software Origin   Public key
        |          |              |
        |  |-------|              |
        |  |   |------------------|        
        |  |   |     
      <<0, 0, 106, 58, 193, 73, 144, 121, 104, 101, 53, 140, 125, 240, 52, 222, 35, 181,
      13, 81, 241, 114, 227, 205, 51, 167, 139, 100, 176, 111, 68, 234, 206, 72>>
  
       NIST P-256  Software Origin   Public key
        |            |              |
        |  |---------|              |
        |  |  |----------------------
        |  |  |    
      <<1, 0, 4, 7, 161, 46, 148, 183, 43, 175, 150, 13, 39, 6, 158, 100, 2, 46, 167,
       101, 222, 82, 108, 56, 71, 28, 192, 188, 104, 154, 182, 87, 11, 218, 58, 107,
      222, 154, 48, 222, 193, 176, 88, 174, 1, 6, 154, 72, 28, 217, 222, 147, 106,
      73, 150, 128, 209, 93, 99, 115, 17, 39, 96, 47, 203, 104, 34>>
  

• Key derivation:

  To be able to retrieve previous public key, the ArchEthic network designs the key derivation through a seed (passphrase) and an index(number of previous public keys/transactions). The procedure is described as follows:

  The seed generates a master key and an entropy used in the child keys generation.
  
                                                             / (256 bytes) Next private key
                        (256 bytes) Master key  --> HMAC-512
                      /                              Key: Master entropy,
    seed --> HMAC-512                                Data: Master key + index)
                      \
                       (256 bytes) Master entropy
  
  

API

Cryptographic functions

deriveKeyPair(seed, index, curve)

It creates a new keypair into hexadecimal format

• seed is hexadecimal encoding or Uint8Array representing the transaction chain seed to be able to derive and generate the keys
• index is the number of transactions in the chain, to generate the actual and the next public key (see below the cryptography section)
• curve is the elliptic curve to use for the key generation (can be "ed25519", "P256", "secp256k1") - default to: "P256"

import 'package:archethic_lib_dart/crypto.dart' as crypto;
import 'package:archethic_lib_dart/model/key_pair.dart';

KeyPair keypair = crypto.deriveKeyPair("mysuperpassphraseorseed", 0);
// uint8ListToHex(keypair.publicKey) => 0100048cac473e46edd109c3ef59eec22b9ece9f99a2d0dce1c4ccb31ce0bacec4a9ad246744889fb7c98ea75c0f0ecd60002c07fae92f23382669ca9aff1339f44216

ecEncrypt(data, publicKey)

Perform an ECIES encryption using a public key and a data

• data Data to encrypt
• publicKey Public key to derive a shared secret and for whom the content must be encrypted

import 'package:archethic_lib_dart/crypto.dart' as crypto;

Uint8List cipher = crypto.ecEncrypt("dataToEncrypt" "00b1d3750edb9381c96b1a975a55b5b4e4fb37bfab104c10b0b6c9a00433ec4646");

aesEncrypt(data, publicKey)

Perform an AES encryption using a key and a data

• data Data to encrypt
• key Symmetric key

import 'package:archethic_lib_dart/crypto.dart' as crypto;

Uint8List cipher = crypto.aesEncrypt("dataToEncrypt" "00b1d3750edb9381c96b1a975a55b5b4e4fb37bfab104c10b0b6c9a00433ec4646");

TransactionBuilding

new TransactionBuilder(type) creates a new instance of the transaction builder

type is the string defining the type of transaction to generate ("keychain", "keychain_access", "transfer", "hosting", "code_proposal", "code_approval", "nft")

The transaction builder instance contains the following methods:

setCode(code)

Add the code in the data.code section of the transaction code is a string defining the smart contract

setContent(content)

Add the content in the data.content section of the transaction content is a string defining the smart contract

setSecret(secret)

Add the secret in the data.keys.secret section of the transaction secret is the hexadecimal encoding or Uint8List representing the encrypted secret

addAuthorizedKey(publicKey, encryptedSecretKey)

Add an authorized public key to decrypt the secret to the data.keys.authorizedKeys section of the transaction

• publicKey is the hexadecimal encoding or Uint8List representing the public key
• encryptedSecretKey is the hexadecimal encoding or Uint8List representing the secret key encrypted with the public key (see ecEncrypt)

addUCOTransfer(to, amount)

Add a UCO transfer to the data.ledger.uco.transfers section of the transaction

• to is hexadecimal encoding or Uint8List representing the transaction address (recipient) to receive the funds
• amount is the number of uco to send (double)

addNFTTransfer(to, amount, nft_address)

Add a NFT transfer to the data.ledger.nft.transfers section of the transaction

• to is hexadecimal encoding or Uint8List representing the transaction address (recipient) to receive the funds
• amount is the number of uco to send (double)
• nft_address is hexadecimal encoding or Uint8List representing the NFT address to spend

addRecipient(to)

Add a recipient (for non UCO transfers, ie. smart contract interaction) to the data.recipient section of the transaction

• to is hexadecimal encoding or Uint8List representing the transaction address (recipient)

build(seed, index, curve, hashAlgo)

Generate address, timestamp, previousPublicKey, previousSignature, originSignature of the transaction and serialize it using a custom binary protocol.

• seed is hexadecimal encoding or Uint8Array representing the transaction chain seed to be able to derive and generate the keys
• index is the number of transactions in the chain, to generate the actual and the next public key (see below the cryptography section)
• curve is the elliptic curve to use for the key generation (can be "ed25519", "P256", "secp256k1") - default to "P256"
• hashAlgo is the hash algorithm to use to generate the address (can be "sha256", "sha512", "sha3-256", "sha3-512", "bake2b") - default to "sha256"

import 'package:archethic_lib_dart/transaction_builder.dart';

var tx = new TransactionBuilder("transfer")
  .addUCOTransfer("00b1d3750edb9381c96b1a975a55b5b4e4fb37bfab104c10b0b6c9a00433ec4646", 0.420) 
  .build("mysuperpassphraseorseed", 0, 'P256');

originSign(privateKey)

Sign the transaction with an origin device private key

• privateKey is hexadecimal encoding or Uint8List representing the private key to generate the origin signature to able to perform the ProofOfWork and authorize the transaction

import 'package:archethic_lib_dart/transaction_builder.dart';
import 'package:archethic_lib_dart/crypto.dart' as crypto;

final KeyPair originKeypair = crypto.deriveKeyPair('origin_seed', 0);
var tx = new TransactionBuilder("transfer")
  .addUCOTransfer("00b1d3750edb9381c96b1a975a55b5b4e4fb37bfab104c10b0b6c9a00433ec4646", 0.420) 
  .build("mysuperpassphraseorseed", 0, 'P256') 
  .originSign(originKeypair.privateKey);

toJSON()

Export the transaction generated into JSON

import 'package:archethic_lib_dart/transaction_builder.dart';

var tx = new TransactionBuilder("transfer")
 .addUCOTransfer("00b1d3750edb9381c96b1a975a55b5b4e4fb37bfab104c10b0b6c9a00433ec4646", 0.420) 
 .build("mysuperpassphraseorseed", 0, 'P256') 
 .toJSON();

Remote Endpoint calls

sendTransaction(tx, endpoint)

Dispatch the transaction to a node by serializing a GraphQL request

• tx represent the built transaction from the transactionBuilder
• endpoint is the HTTP URL to a ArchEthic node (acting as welcome node)

Don't available for the moment... soon...

getTransactionIndex(address, endpoint)

Query a node to find the length of the chain to retrieve the transaction index

• address Transaction address (in hexadecimal)
• endpoint Node endpoint

import 'package:archethic_lib_dart/services/api_service.dart';

int index = await ApiService().getTransactionIndex(
       '00b1d3750edb9381c96b1a975a55b5b4e4fb37bfab104c10b0b6c9a00433ec4646', 'http://www.archethic.net');
// 0

getStorageNoncePublicKey(endpoint)

Query a node to find the public key of the shared storage node key

• endpoint Node endpoint

import 'package:archethic_lib_dart/services/api_service.dart';

String storageNoncePublicKey =
       await await ApiService().getStorageNoncePublicKey('http://www.archethic.net');
// 00b1d3750edb9381c96b1a975a55b5b4e4fb37bfab104c10b0b6c9a00433ec4646

Coingecko functions

getCoinsResponse()

Get all Uniris Coin infos with http request https://api.coingecko.com/api/v3/coins/uniris

getCoinsChart(currency, nbDays)

Get Uniris Coin infos (Prices, Marketcaps, Total Volumes) for a period with http request https://api.coingecko.com/api/v3/coins/uniris/market_chart?vs_currency=currency&days=nbDays

getSimplePrice(currency)

Get Uniris Coin infos (BTC Price, Local Currency Price) with https://api.coingecko.com/api/v3/simple/price?ids=uniris&vs_currencies=currency

getCoinsCurrentData()

Get Uniris Coin infos (name, price, market, ... including exchange tickers) with https://api.coingecko.com/api/v3/coins/uniris

Running the tests

flutter test