Deversifi Javascript Trading API

A js client library for DeversiFi - StarkWare orders

Note: This library is for DeversiFi. A test version of the platform to use during integrations is connected to the Ropsten test network at https://app.stg.deversifi.com // https://api.stg.deversifi.com

Contents

• Installation
  • NPM
  • Prebuild for browser
• Setup
  • Pre Requisites
  • Instancing
    • Using MetaMask or a local node
    • Using a private key
    • Configuration
• API Authentication
• Registering
• Approving tokens
• Depositing tokens
• Placing an order
• Withdrawing tokens
  • Requesting a withdrawal
  • Withdraw on chain
• Cancelling Orders
• Authenticated data endpoints
• More examples
  • Gas Price
  • Custom order ID
• Troubleshooting
• Developing
  • Setup
  • Implementing-a-new-future
• Useful Links
• Developing

Installation

NPM

  npm i dvf-client-js

Prebuild for browser

Alternatively on the browser you can use the standalone build

<script src="http://path/to/dist/dvf.js"></script>

Setup

Pre Requisites

• An Ethereum wallet
• A web3 provider with your account or a private key
  • Such as MetaMask, keystore file, hardware wallet or raw private key

Instancing

Using MetaMask or a local node

// In case of MetaMask make sure you call ethereum.enable() before using it
const DVF = require('dvf-client-js')
const dvf = await DVF()

Using a private key

const HDWalletProvider = require("@truffle/hdwallet-provider");
const Web3 = require("Web3")

const privateKey = '8F085...' // Account's private key
const rpcUrl = 'https://mainnet.infura.io/v3/9e28b...'

const provider = new HDWalletProvider(privateKey, rpcUrl)
const web3 = new Web3(provider)

dvf = await DVF(web3)

View the full example: /examples/node_sell_eth_infura.js

Configuration

It's possible to overwrite values on the configuration on a per instance basis.

The default configuration can be overwritten with an optional parameter userConf when calling the DVF function.

Parameters

• api string? (default https://api.stg.deversifi.com) API endpoint you are connecting to Staging (ropsten): https://api.stg.deversifi.com, Production (mainnet): https://api.deversifi.com)
• gasApi string? (default https://ethgasstation.info)
• defaultGasLimit number? (default 200000)
• defaultGasPrice number? (default 50000000000)
• defaultStarkExpiry number? (default 720) Expiration time for transfers and orders in hours
• defaultNonceAge number? (default 43200) Nonce age in seconds
• defaultProvider string? (default http://localhost:8545) In case no web3 provider is provided we will try connecting to this default
• autoLoadUserConf boolean? - Enables integrators to select if they want to call getUserConfig upon initialization
• autoLoadExchangeConf boolean? - Enables integrators to select if they want to call getConfig upon initialization

For instance:

  dvf = await DVF(web3, {
    api: 'https://your-custom-api-address',
    gasStationApiKey: 'a1b2c3...
  })

The configuration is also merged with the configuration provided by the exchange on the HTTP endpoint /v1/trading/r/getConf which at the moment looks similar to this:

{
   "DVF":{
      "defaultFeeRate":0.002,
      "deversifiAddress":"0xaf8ae6955d07776ab690e565ba6fbc79b8de3a5d",
      "starkExContractAddress":"0x5d22045DAcEAB03B158031eCB7D9d06Fad24609b",
      "withdrawalBalanceReaderContractAddress":"0x650ca2dca7e2e2c8be3bb84e0a39dd77891d4d1e",
      "exchangeSymbols":[
         "ETH:USDT",
         "MKR:ETH",
         "MKR:USDT"
      ],
      "tempStarkVaultId":1,
      "minDepositUSDT":1
   },
   "tokenRegistry":{
      "ETH":{
         "decimals":18,
         "quantization":10000000000,
         "minOrderSize":0.05,
         "starkTokenId":"0xb333e3142fe16b78628f19bb15afddaef437e72d6d7f5c6c20c6801a27fba6"
      },
      "MKR":{
         "decimals":18,
         "quantization":10000000000,
         "minOrderSize":0.025,
         "tokenAddressPerChain": {
            "ETHEREUM": "0x9f8f72aa9304c8b593d555f12ef6589cc3a579a2"
         },
         "starkTokenId":"0x1a4af39d27ce2e3445ed084809e5bc36d03918df04b7e2b6ee3c769a9892600"
      }
   }
}

The complete compiled configuration is accessible through dvf.config, for instance:

const dvf = await DVF()

const config = dvf.config

API Authentication

Authentication to make all authenticated requests is done by signing a nonce using an Ethereum private key. Signing is handled by the Deversifi client library if the account is available and unlocked or if the web3 provider supports it. Otherwise the message and signature need to be prepared separately.

Parameters

• nonce string Nonce which is used to provide the time until which this nonce is valid. It is presented as seconds since epoch.
• signature string The signature obtained by signing the nonce with your private ethereum key.

const nonce = (Date.now() / 1000).toString()
const signature = await dvf.sign(nonce)

Registering

This method is used to register a stark public key that corresponds to an Ethereum public address or a trading key.

Parameters

• starkPublicKey Object
  • x string - First 32 bits of stark public key
• nonce string Nonce which is used to provide the time until which this nonce is valid. It is presented as seconds since epoch.
• signature string The signature obtained by signing the nonce with your private ethereum key.
• contractWalletAddress string? Address of the deployed contract wallet (only for contract wallet integrations)

Returns Promise<UserConfigResponse>

Approving Tokens

When depositing an ERC20 Ethereum-based token for the first time from a specific account, you are required to approve it to interact with the smart contracts, this is not required for ETH.

Parameters

• token string Token symbol that's available in dvf.config.tokenRegistry

Returns Promise<PromiEvent>

const token = 'ETH'
await dvf.contract.approve(token)

This step does not need to be repeated again, and subsequently you are required only to call the deposit function.

Depositing tokens

This method is used to deposit the tokens to the smart contract and submit a signed notification of a new deposit made to the API.

Parameters

• token string Token symbol available in dvf.config.tokenRegistry to be deposited
• amount number || string Amount of tokens to be deposited
• starkPrivateKey string Trading key
• nonce string? Nonce which is used to provide the time until which this nonce is valid. It is presented as seconds since epoch.
• signature string? The signature obtained by signing the nonce with your private ethereum key.

Returns Promise<{...PromiEvent, ...DepositResponse}>

const token = 'ETH'
const amount = 100

const deposit = await dvf.deposit(token, amount, tradingKey)

Placing an order

This authenticated endpoint is used to place an order.

Parameters

• symbol string Pair which you wish to trade
• amount number || string Order amount specified in the first currency in the symbol (i.e. ZRXETH). For a sell, amount is negative. Amount accepts either maximum 8 d.p, or as many decimals as are available on the relevant token's smart contract if it is fewer than 8.
• price number || string Order price specified in the second currency in the symbol (i.e. ZRXETH). Prices should be specified to 5 s.f. maximum.
• nonce string? Nonce which is used to provide the time until which this nonce is valid. It is presented as seconds since epoch.
• signature string? The signature obtained by signing the nonce with your private ethereum key.
• starkPrivateKey string? Trading key (for keystore etc.)
• ledgerPath string? Ledger derivation path if using ledger
• isPostOnly boolean? Flag to indicate if the order is post-only.
• isHidden boolean? Flag to indicate if the order is hidden.
• validFor number? Validation time in hours
• feeRate number? Fee rate if known
• cid string? Optional custom order ID that could be set when placing order and used later to retrieve order. This ID is unique per user (user A and B can each have an order with cid = AAA, but the same user cannot have two orders with the same cid). See example
• gid string?
• partnerId string?
• ethAddress string?
• type string? Order type (EXCHANGE LIMIT, EXCHANGE MARKET)
• protocol string? (default stark)

Returns Promise<SubmitOrderResponse>

const symbol = 'NEC:ETH'
const amount = -15
const price = 0.0025

const orderId = await dvf.submitOrder(symbol, amount, price)

Getting Orders

This method allows you to get a specific order by orderId or cid.

Parameters

• orderId string? ID of the order
• nonce string? Nonce which is used to provide the time until which this nonce is valid. It is presented as seconds since epoch.
• signature string? The signature obtained by signing the nonce with your private ethereum key.
• cid string? If order was placed with custom order ID (cid) property set, it can be canceled using same cid.

Returns Promise<CancelOrderResponse>

const orderID = '123'
const customID = 'cid-123'

const order = await dvf.getOrder({ orderId: orderID })
// or
const order = await dvf.getOrder({ cid: customID })

Cancelling Orders

This method allows you to cancel a specific order by orderId or cid.

Parameters

• orderId string ID of the order
• nonce string? Nonce which is used to provide the time until which this nonce is valid. It is presented as seconds since epoch.
• signature string? The signature obtained by signing the nonce with your private ethereum key.
• cid string? If order was placed with custom order ID (cid) property set, it can be canceled using same cid.

Returns Promise<CancelOrderResponse>

const orderID = '123'
const customID = 'cid-123'

const response = await dvf.cancelOrder({ orderId: orderID })
// or
const response = await dvf.cancelOrder({ cid: customID })

Withdrawing tokens

Requesting a withdrawal

This method submits a request for a new withdrawal.

Parameters

• recipientEthAddress string Trading key
• token string Token symbol available in dvf.config.tokenRegistry to be withdrawn
• amount number || string Amount of tokens to be withdrawn

Returns Promise<WithdrawResponse>

const token = 'ETH'
const amount = 100
const withdrawal = await await dvf.transferAndWithdraw({
  recipientEthAddress: address,
  token,
  amount
})

Withdraw on chain

This method calls the contract and withdraws the tokens to your wallet

Parameters

• token string Token symbol available in dvf.config.tokenRegistry to be withdrawn

Returns Promise<{ transactionHash: string }>

const token = 'ETH'
const txHash = await dvf.withdrawOnchain(token)

Authenticated data endpoints

If you already have an unlocked wallet available to web3 to use for signing, you can simply get data from the API as follows:

Note: You should reuse the nonce and signature and pass them to these methods while they are valid to avoid unnecessary signing

Parameters

• nonce string? Nonce which is used to provide the time until which this nonce is valid. It is presented as seconds since epoch.
• signature string? The signature obtained by signing the nonce with your private ethereum key.

// Get all open orders
const openOrders = await dvf.getOrders()

// Get all historical orders
const historicalOrders = await dvf.getOrdersHist()

// Get specific order 
const id = "123"
const order = await dvf.getOrder(id)

// Get exchange balances
const balance = await dvf.getBalance()

// Get deposits
const deposits = await dvf.getDeposits()

// Get withdrawals 
const withdrawals = await dvf.getWithdrawals()

// Get user config
const userConfig = await dvf.getUserConfig()

More Examples

Aside from these examples, there are complete examples in the examples folder

Gas Price

You can setup a default custom gas price by setting up the 'defaultGasPrice' property

const dvf = await DVF()

dvf.set('defaultGasPrice', web3.utils.toWei('2', 'gwei'))

DVF Client calls https://ethgasstation.info API to get the current gas prices and calculate a safe gas price for Ethereum transactions. Access to the ETH Gas Station API is free, but rate limited if you are not using an API key. If a ETH Gas Station API key is not provided then a recommended gas price is used which is available in dvf.recommendedGasPrices.

To configure your api key with dvf client please pass this as a userConf parameter when initialising DVF:

javascript
  dvf = await DVF(web3, {
    gasStationApiKey: 'a1b2c3...'
  })

or by setting the 'gasStationApiKey' property:

dvf.set('gasStationApiKey', 'a1b2c3...')

Custom order ID

Property cid can be used to give order custom identificator for further tracking.

const symbol = 'ETH:USDT'
const amount = -1.42
const price = 3000

const customOrderID = `short-` + Math.random().toString(36).substring(7)

await dvf.submitOrder({
  symbol, 
  amount, 
  price,
  cid: customOrderID,
})

// ...
// Later we can use `cid` to get order
const order = await dvf.getOrder({cid: customOrderID})

// or cancel it
await dvf.cancelOrder({cid: customOrderID})

Troubleshooting

A list of error codes returned by the API and reasons are available here. Some more detailed explanations can also be found in the API Documentation.

If you have suggestions to improve this guide or any of the available documentation, please raise an issue on Github, or email feedback@Deversifi.com.

Links

• API documentation

Developing

Setup

• git clone
• npm install

Implementing a new feature

Starting by watching the test files ( you will need a node running )

$ npm run test:watch

• Write the tests for your new features on the ./test/
• Add your tests to './test/index.js' file if necessary
• Create your features on ./src/ folder

• You will need a ropsten node to do blockchain related tests

Testing

On node.js

$ npm run test

On a headless browser ( using browserify and mochify )

$ npm run test:web

Manually on your browser on a browser console

• Very useful in case you want to issue commands from Google Chrome while using MetaMask !

$ npm run build:web:run

• Open your browser on http://localhost:2222

Building for browsers

• This will build the whole library as one big ugly standalone js file ( uses browserify )

$ npm run build

License

MIT