DKosov/npm-repo-test

VIA SDK typescript

A small blazing fast wrapper over the VIA Router API for on-chain and cross-chain swaps. Our API allows you to find the best route for moving funds between chains!

Feature List

feature	remark	method
get routes	Swaps/bridges cheapest routes	getRoutes
check allowance	Allowance to check whether it's needed or not to approve	getAllowanceStatus
build approval transaction	The transaction that approves the VIA contract to spend your token	buildApprovalTx
build transaction	The transaction that will perform a swap/bridge according to the route	buildTx

Installing

npm i @viaprotocol/router-sdk

Usage

First you need to initialize a VIA Client instance:

import Via from '@viaprotocol/router-sdk';

const DEFAULT_API_KEY = 'e3db93a3-ae1c-41e5-8229-b8c1ecef5583';
const cli = new Via({apiKey: DEFAULT_API_KEY, url: 'https://router-api.via.exchange', timeout: 30});

Get the best routes.

const fromChainId = 1;
const fromTokenAddress = '0x0000000000000000000000000000000000000000';
const fromAmount = Math.pow(10, 18);
const toChainId = 56;
const toTokenAddress = '0x0000000000000000000000000000000000000000';
const fromAddress = '0x856cc59aaE47997a1C8D5472Fc8dfef27821235d';  // might be null
const multiTx = false;  // whether to return routes with multiple user transactions

const routes = await cli.getRoutes(
    {
        fromChainId,
        fromTokenAddress,
        fromAmount,
        toChainId,
        toTokenAddress,
        fromAddress,
        multiTx
    }
);

Get allowance status You must approve the contract to spend your token. You can get route_id from the route you like received above in the code snippet.

const routeId = routes.routes[0];
const chainId = fromChainId;
const owner = "YOUR_WALLET_ADDRESS";
const tokenAddress = fromTokenAddress;
const numAction = 0;  // number of action in routes

const allowanceStatus = await cli.getAllowanceStatus(
    {owner, routeId, numAction}
);

Build approval transaction. Returns the transaction that approves the VIA API to spend your token.

const amount = fromAmount;

tx = await cli.buildApprovalTx(
    {routeId, owner, numAction}
)

Now you can build the transaction that will perform a crosschain swap according to the route.

# amount out minimal, you can get it from get_routes as to_token_amount
output = routes.routes[0].toTokenAmount

tx = await cli.buildTx(
    {
        routeId,
        fromAddress,
        receiveAddress,
        numAction
    }
)