DEX API
Get allowance

Get allowance#

Note
You need to use a third-party method since OKX DEX has discontinued its interface that queries the authorized amount of a transaction. The recommended method is as follows.

Third-party query method#

Taking ETH chain as an example#

  • This demo is in JavaScript
  1. Connect to an Ethereum node: You need to ensure that you have connected to an available Ethereum node. You can use web3.js or other Ethereum development libraries to connect to the node. In the code, you need to specify the node's HTTP or WebSocket endpoint.
  2. Obtain a token contract instance: Using the contract address and ABI of the token, you need to create an instance of the token contract. You can use the web3.eth.Contract in web3.js to achieve this. Pass the contract address and ABI as arguments to the contract instance.
  3. Query the authorized amount: Query the authorized allowance by calling the allowance function of the contract instance. This function requires two parameters: the owner's address and the authorized party's address (spenderAddress). You can query the authorized allowance by providing these two addresses during the call.
  4. The spenderAddress can refer to the dexTokenApproveAddress from Here in the Response interface.。
const { Web3 } = require('web3');
// Connect to an Ethereum node
const web3 = new Web3('https://xxxxx');
// token address and  ABI
const tokenAddress = '0xxxxxxxxx';
// user address
const ownerAddress = '0xxxxxxxx';
// ETH dex token approval address
const spenderAddress = '0x40aa958dd87fc8305b97f2ba922cddca374bcd7f';


const tokenABI = [
    {
        "constant": true,
        "inputs": [
            {
                "name": "_owner",
                "type": "address"
            },
            {
                "name": "_spender",
                "type": "address"
            }
        ],
        "name": "allowance",
        "outputs": [
            {
                "name": "",
                "type": "uint256"
            }
        ],
        "payable": false,
        "stateMutability": "view",
        "type": "function"
    }
];


// Create token contract instance
const tokenContract = new web3.eth.Contract(tokenABI, tokenAddress);
// Query token approve allowance function
async function getAllowance(ownerAddress, spenderAddress) {
    try {
        const allowance = await tokenContract.methods.allowance(ownerAddress, spenderAddress).call();
        console.log(`Allowance for ${ownerAddress} to ${spenderAddress}: ${allowance}`);
    } catch (error) {
        console.error('Failed to query allowance:', error);
    }
}

getAllowance(ownerAddress, spenderAddress).then(r => console.log(r));
Table of contents