Quickstart

yarn add @depay/web3-exchanges

or

npm install --save @depay/web3-exchanges

import { all, findByName, route } from '@depay/web3-exchanges'

all
// [
//   { name: 'uniswap_v2', label: 'Uniswap v2', logo: '...' }
//   { name: 'pancakeswap_v2', label: 'PancakeSwap v2', logo: '...' }
//   { name: 'cryptoswap', label: 'CryptoSwap', logo: '...' }
//   ...
// ]

let exchange = findByName('uniswap_v2')
// { name: 'uniswap_v2', label: 'Uniswap v2', logo: '...' }

let routes = await route({
  blockchain: 'ethereum',
  tokenIn: '0xa0bEd124a09ac2Bd941b10349d8d224fe3c955eb',
  tokenOut: '0xdAC17F958D2ee523a2206206994597C13D831ec7',
  amountIn: 1,
  fromAddress: '0x5Af489c8786A018EC4814194dC8048be1007e390',
  toAddress: '0x5Af489c8786A018EC4814194dC8048be1007e390'
}) // returns routes sorted by cost-effectiveness (best first)

// use connected wallet to sign and send the swap transaction
import { getWallet } from '@depay/web3-wallets'

let wallet = getWallet()

wallet.sendTransaction(route.transaction)

Support

This library supports the following blockchains:

• Ethereum
• BNB Smart Chain
• Polygon

This library supports the following decentralized exchanges:

• Uniswap v2
• PancakeSwap v2
• Quickswap

Data Structures

Exchange

Decentralized exchange data is provided in the following structure:

{
  blockchain: String (e.g. ethereum)
  name: String (e.g. uniswap_v2)
  alternativeNames: Array (e.g. ['pancake'])
  label: String (e.g. Uniswap v2)
  logo: String (base64 encoded PNG),
  contracts: Object (contains important contract addresses and apis to interact with the exchange)
}

Swap

A Swap configuration is fed into the route function:

{
  tokenIn: String (e.g. '0xa0bEd124a09ac2Bd941b10349d8d224fe3c955eb')
  tokenOut: String (e.g. '0xdAC17F958D2ee523a2206206994597C13D831ec7')
  amountIn: Human Readable Number (e.g. 1.2)
  amountInMax: Human Readable Number (e.g. 1.2)
  amountOut: Human Readable Number (e.g. 1.2)
  amountOutMin: Human Readable Number (e.g. 1.2)
  fromAddress: '0x5Af489c8786A018EC4814194dC8048be1007e390'
  toAddress: '0x5Af489c8786A018EC4814194dC8048be1007e390'
}

The following combinations of provided amounts are possible:

• Only amountIn, amountOutMin will be calculated automatically and can vary
• Only amountOut, amountInMax will be calculated automatically and can vary
• Only amountInMax, amountOut will be calculated automatically and can vary
• Only amountOutMin, amountIn will be calculated automatically and can vary
• amountIn and amountOutMax (routing will stick to both)
• amountOut and amountInMin (routing will stick to both)

Route

Routes are returned by calling route. A single Route has the following structure:

{
  tokenIn: String (e.g. '0xa0bEd124a09ac2Bd941b10349d8d224fe3c955eb')
  tokenOut: String (e.g. '0xdAC17F958D2ee523a2206206994597C13D831ec7')
  path: Array (e.g. ['0xa0bEd124a09ac2Bd941b10349d8d224fe3c955eb', '0xc02aaa39b223fe8d0a0e5c4f27ead9083c756cc2', '0xdAC17F958D2ee523a2206206994597C13D831ec7'])
  amountIn: BigNumber (e.g. '1000000000000000000')
  amountOutMin: BigNumber (e.g. '32000000000000000000')
  amountOut: BigNumber (e.g. '32000000000000000000')
  amountInMax: BigNumber (e.g. '1000000000000000000')
  fromAddress: '0x5Af489c8786A018EC4814194dC8048be1007e390'
  toAddress: '0x5Af489c8786A018EC4814194dC8048be1007e390'
  transaction: Transaction (see @depay/web3-wallets for details)
  exchange: Exchange (see [Exchange data structure](#exchange))
}

See @depay/web3-wallets for details about the transaction format.

Functionalities

all: Stores all information for all decentralized exchanges

import { all } from '@depay/web3-exchanges'

all
// [
//   { name: 'uniswap_v3', label: 'Uniswap v3', logo: '...' }
//   { name: 'pancakeswap_v2', label: 'PancakeSwap v2', logo: '...' }
//   ...
// ]

findByName: Get decentralized exchanged by name (name usually contains version, too)

import { findByName } from '@depay/web3-exchanges'

findByName('uniswap_v2')
// { name: 'uniswap_v2', label: 'Uniswap v2', logo: '...' }

findByName('pancakeswap_v2')
// { name: 'pancakeswap_v2', label: 'PancakeSwap v2', logo: '...' }

route: Routes a Swap configuration and returns routes to perform the Swap

import { route } from '@depay/web3-exchanges'

let routes = route {
  tokenIn: '0xa0bEd124a09ac2Bd941b10349d8d224fe3c955eb',
  tokenOut: '0xdAC17F958D2ee523a2206206994597C13D831ec7',
  amountIn: 1,
  amountOutMin: 2,
  fromAddress: '0x5Af489c8786A018EC4814194dC8048be1007e390',
  toAddress: '0x5Af489c8786A018EC4814194dC8048be1007e390'
} // returns routes sorted by cost-effectiveness (best first)

// use connected wallet to sign and send the swap transaction
import { getWallet } from '@depay/web3-wallets'

let wallet = getWallet()

wallet.sendTransaction(routes[0].transaction)

route can also be called on concrete exchanges:

import { findByName } from '@depay/web3-exchanges'

let exchange = findByName('uniswap_v2')

let route = await exchange.route({
  blockchain: 'ethereum',
  tokenIn: '0xa0bEd124a09ac2Bd941b10349d8d224fe3c955eb',
  tokenOut: '0xdAC17F958D2ee523a2206206994597C13D831ec7',
  amountIn: 1,
  amountOutMin: 2,
  fromAddress: '0x5Af489c8786A018EC4814194dC8048be1007e390',
  toAddress: '0x5Af489c8786A018EC4814194dC8048be1007e390'
})

// use connected wallet to sign and send the swap transaction
import { getWallet } from '@depay/web3-wallets'

let wallet = getWallet()

wallet.sendTransaction(route.transaction)

Development

Get started

yarn install
yarn dev

Release

npm publish