Approve order fill

Approve token spending via EIP-2612 permit for SX Bet order execution.

POST /orders/approve

EIP-2612 Permit

JavaScript

import { Contract, JsonRpcProvider, MaxUint256, Wallet } from "ethers";

async function approveOrderFill() {
  const privateKey = process.env.SX_PRIVATE_KEY;
  const tokenAddress = process.env.TOKEN_ADDRESS;

  // get the following from https://api.sx.bet/metadata
  const tokenTransferProxyAddress = process.env.TOKEN_TRANSFER_PROXY_ADDRESS;
  const chainId = Number(process.env.CHAIN_ID); // Mainnet — use 79479957 for testnet

  const wallet = new Wallet(
    privateKey,
    new JsonRpcProvider(process.env.RPC_URL) // find this under the 'references' section
  );

  const tokenContract = new Contract(
    tokenAddress,
    [
      {
        inputs: [
          { internalType: "address", name: "usr", type: "address" },
          { internalType: "uint256", name: "wad", type: "uint256" },
        ],
        name: "approve",
        outputs: [{ internalType: "bool", name: "", type: "bool" }],
        stateMutability: "nonpayable",
        type: "function",
      },
      {
        inputs: [{ internalType: "address", name: "owner", type: "address" }],
        name: "nonces",
        outputs: [{ internalType: "uint256", name: "", type: "uint256" }],
        stateMutability: "view",
        type: "function",
      },
      {
        inputs: [],
        name: "name",
        outputs: [{ internalType: "string", name: "", type: "string" }],
        stateMutability: "view",
        type: "function",
      },
    ],
    wallet
  );

  const nonce = await tokenContract.nonces(wallet.address);
  const tokenName = await tokenContract.name();

  const domain = {
    name: tokenName,
    version: "1",
    chainId,
    verifyingContract: tokenAddress,
  };

  const types = {
    Permit: [
      { name: "owner", type: "address" },
      { name: "spender", type: "address" },
      { name: "value", type: "uint256" },
      { name: "nonce", type: "uint256" },
      { name: "deadline", type: "uint256" },
    ],
  };

  const deadline = Math.floor(Date.now() / 1000) + 7200; // 2 hours

  const value = {
    owner: wallet.address,
    spender: tokenTransferProxyAddress,
    value: MaxUint256,
    nonce,
    deadline,
  };

  const approveProxySignature = await wallet.signTypedData(domain, types, value);

  const apiPayload = {
    owner: wallet.address,
    spender: tokenTransferProxyAddress,
    tokenAddress,
    value: MaxUint256.toString(),
    deadline,
    signature: approveProxySignature,
  };

  const response = await fetch("https://api.sx.bet/orders/approve", { // Mainnet — use https://api.toronto.sx.bet for testnet
    method: "POST",
    body: JSON.stringify(apiPayload),
    headers: { "Content-Type": "application/json" },
  });
}

201

{
  "status": "success",
  "data": {
    "hash": "0x840763ae29b7a6adfa0e315afa47be30cdebd5b793d179dc07dc8fc4f0034965"
  }
}

If you don’t wish to do this programmatically, you can simply go to sx.bet (or toronto.sx.bet for testnet), place a test bet with the account and token you’ll be using, and you will be good to go.

If you want to do it programmatically, see the code sample below.

This endpoint approves the specified value to be spent by spender on behalf of owner for token transfers that occur as part of the Filling orders flow according to Ethereum’s EIP-2612 Permit Extension. Note that deadline field here is only used during signature verification and that the value set will be the spender’s allowance until changed or revoked.

Body

application/json

owner · string · required

Address of the taker granting approval to TokenTransferProxy for filling orders on their behalf

spender · string · required

The address of the account which will be able to spend token amounts on behalf of the owner. In this case, the spender should be TokenTransferProxy address

tokenAddress · string · required

The token address to grant approval for

value · string · required

The token amount to grant approval for, in Ethereum units

deadline · integer · required

The deadline as a UNIX timestamp format used in signature verification

signature · string · required

Your wallet signature over the payload. See the example of how to compute this.

Response

201 - application/json

status · string

success or failure if the request succeeded or not

data · object

Show child attributes