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Check and Set Allowances

note

You need to provide allowance for the wrapped version of the native asset to perform native asset transfers/swaps.

Getting Allowance​

const src_token_allowance = await routerprotocol.getSourceTokenAllowance("TOKEN_ADDRESS", "DESTINATION_CHAIN_ID", "USER_ADDRESS")

Setting Approval​

await routerprotocol.approveSourceToken("TOKEN_ADDRESS","USER_ADDRESS", "AMOUNT_TO_BE_APPROVED", "DESTINATION_CHAIN_ID", "SOURCE_SIGNER")

Example​

import { RouterProtocol } from "@routerprotocol/router-js-sdk"
import { ethers } from "ethers";

const main = async() => {

// initialize a RouterProtocol instance

// setting the arguments for the cross-chain swap
let args = {
    amount: (ethers.utils.parseUnits("10.0", 6)).toString(), // 10 USDC
    dest_chain_id: 250, // Fantom
    src_token_address: "0x2791Bca1f2de4661ED88A30C99A7a9449Aa84174", // USDC on Polygon
    dest_token_address: "0x04068DA6C83AFCFA0e13ba15A6696662335D5B75", // USDC on Fantom
    user_address: "YOUR_WALLET_ADDRESS",
    fee_token_address: "0x16ECCfDbb4eE1A85A33f3A9B21175Cd7Ae753dB4", // ROUTE on Polygon
    slippage_tolerance: 1.0
}

// getting allowance
const wallet = new ethers.Wallet("YOUR_PRIVATE_KEY", provider) // provider was set up while initializing an instance of RouterProtocol
// use provider.getSigner() method to get a signer if you're using this for a UI

let src_token_allowance = await routerprotocol.getSourceTokenAllowance(args.src_token_address, args.dest_chain_id, args.user_address)
if(src_token_allowance.lt(ethers.constants.MaxUint256)){
        await routerprotocol.approveSourceToken(args.src_token_address, args.user_address, ethers.constants.MaxUint256, args.dest_chain_id, wallet)
}

if(ethers.utils.getAddress(args.src_token_address) !== ether.utils.getAddress(args.fee_token_address)){
    let fee_token_allowance = await routerprotocol.getFeeTokenAllowance(args.fee_token_address, args.dest_chain_id, args.user_address)
    if(fee_token_allowance.lt(ethers.constants.MaxUint256)){
        await routerprotocol.approveFeeToken(args.fee_token_address, args.user_address, ethers.constants.MaxUint256, wallet)
    }
}

}

main()