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"Cook a Recipe" anonymously with RAILGUN Quickstart
Given a full Recipe and its inputs, RAILGUN Wallet SDK will generate a zero-knowledge proof and a final serialized transaction for the RAILGUN Relay Adapt contract.
This final transaction can be submitted to the blockchain by any wallet, including a Relayer.
cook-recipe-example.ts
import {
RecipeERC20Info,
ZeroXSwapRecipe,
RecipeInput,
RecipeOutput
} from '@railgun-community/cookbook';
import {
NetworkName,
} from '@railgun-community/shared-models';
const sellERC20Info: RecipeERC20Info = {
tokenAddress: '0x6B175474E89094C44Da98b954EedeAC495271d0F', // DAI
decimals: BigInt(18)
}
const buyERC20Info: RecipeERC20Info = {
tokenAddress: '0xdac17f958d2ee523a2206206994597c13d831ec7', // USDT
decimals: BigInt(18)
}
const slippagePercentage = 0.05;
const swap = new ZeroXSwapRecipe(sellERC20Info, buyERC20Info, slippagePercentage);
// Inputs that will be unshielded from private balance.
const unshieldERC20Amounts = [
{
...sellERC20Info,
amount: BigInt('0x10'), // hexadecimal amount
}
];
const recipeInput: RecipeInput = { NetworkName.Ethereum, unshieldERC20Amounts };
const {
crossContractCalls,
erc20AmountRecipients,
nftRecipients,
feeERC20AmountRecipients,
minGasLimit,
} = await swap.getRecipeOutput(recipeInput);
// Outputs to re-shield after the Recipe multicall.
const shieldERC20Addresses = erc20AmountRecipients.map(({tokenAddress}) => tokenAddress);
// RAILGUN Wallet will generate a [unshield -> call -> re-shield]
// transaction enclosing the Recipe multicall.
const { gasEstimate } = await gasEstimateForUnprovenCrossContractCalls(
...
unshieldERC20Amounts,
...
shieldERC20Addresses,
...
crossContractCalls,
...
)
await generateCrossContractCallsProof(
...
unshieldERC20Amounts,
...
shieldERC20Addresses,
...
crossContractCalls,
...
)
const { transaction } = await populateProvedCrossContractCalls(
...
unshieldERC20Amounts,
...
shieldERC20Addresses,
...
crossContractCalls,
...
);
// Submit transaction to RPC.
await wallet.sendTransaction(transaction);
// Note: use @railgun-community/waku-relayer-client to submit
// through a Relayer instead of signing with your own wallet.