Deprecating This Week: Get ERC20 token allowance

Moralis General
#1

Hello,

Could you please confirm if the deprecation of this endpoint will affect dApps that are using the Moralis Self-Hosted server?

Thank you.

#2

Hi @zrco

The selfhosted server even use the same APIs in the server code, so yes they will be affected.:pray:

#3

Hi @johnversus

Is there a workaround for this issue?

#4

The suggested alternate endpoint is to use wallet token approval endpoint. Please try using it to get all the allowed approval data

#5

Is this endpoint supported in Moralis v1? Do I need to update the Self-Hosted Server in order to enable Wallet Token Approvals?

#6

It is not available in v1 sdk. Maybe you need to create a new cloud function with this endpoint and then call the cloud function from your client to use it with the required params.

#7

I was able to replace the endpoint with the following workaround.

function getProviderAndSigner() {
    if (typeof window.ethereum !== 'undefined') {
      const provider = new ethers.providers.Web3Provider(window.ethereum);
      await provider.send('eth_requestAccounts', []); 
      const signer = provider.getSigner();
      return { provider, signer };
    } else {
      throw new Error('No Web3 provider found. Please install MetaMask.');
    }
  }
export async function getTokenAllowance(token_address, chainId) {
  try {
    // Get the signer from the provider
    const { signer } = await getProviderAndSigner();
    const tokenABI = [
      "function approve(address spender, uint256 amount) public returns (bool)",
      "function allowance(address owner, address spender) public view returns (uint256)"
    ];
    const tokenContract = new ethers.Contract(token_address, tokenABI, signer);
    const ownerAddress = await signer.getAddress();
    const spenderAddress = dappContractAddress(chainId); 
    const allowance = await tokenContract.allowance(ownerAddress, spenderAddress);
    return allowance.toString();
  } catch (error) {
    console.error("Error fetching token allowance:", error);
    throw new Error(`Failed to get token allowance: ${error.message}`);
  }
}
#8