Searching for contract transactions throws 'unsupported topic count'

[tggm]

Hello!

I'm trying to list contract Transfer operations from a given wallet address. The objective is to (eventually) determine tokens that were staked in some vault address, so the first step would be to identify Transfer() calls on the contract from the wallet.

I've been trying multiple examples I found here or on the documentations site but I always end up with an "unsupported token count" error.

Here's what I'm doing. Note: I'm using the Bscscan Provider, which AFAIK, only overrides the API url.

import { Contract } from "ethers";
import { BscscanProvider } from "@ethers-ancillary/bsc";
import ERC20ABI from "human-standard-token-abi";

const initializeProvider = () => {
  return new BscscanProvider("bsc-mainnet", "APIKEYXXXXXXX");
};

const getTokenContract = async (tokenAddress) => {
  return new Contract(tokenAddress, ERC20ABI, initializeProvider());
};

const getTokenTransactions = async (tokenContract, address) => {
  var filter = tokenContract.filters.Transfer(address);

  return tokenContract.queryFilter(filter, -1000000, "latest");
};

Running this on node's interpreter

import("my-stuff.js").then(module => { myModule = module });

// CAKE token.
contract = await myModule.getTokenContract("0x0e09fabb73bd3ade0a17ecc321fd13a19e81ce82") 

myModule.getTokenTransactions(contract, "WALLET_ADDRESS")

Returns:

Promise {
  <pending>,
  [Symbol(async_id_symbol)]: 405,
  [Symbol(trigger_async_id_symbol)]: 5,
  [Symbol(destroyed)]: { destroyed: false }
}
> Uncaught:
Error: unsupported topic count (topics=[......], code=UNSUPPORTED_OPERATION, version=providers/5.4.5)
    at Logger.makeError (./node_modules/@ethersproject/logger/lib/index.js:199:21)
    at Logger.throwError (./node_modules/@ethersproject/logger/lib/index.js:208:20)
    at BscscanProvider.<anonymous> (./node_modules/@ethersproject/providers/lib/etherscan-provider.js:416:40)
    at step (./node_modules/@ethersproject/providers/lib/etherscan-provider.js:48:23)
    at Object.next (./node_modules/@ethersproject/providers/lib/etherscan-provider.js:29:53)
    at ./node_modules/@ethersproject/providers/lib/etherscan-provider.js:23:71
    at new Promise (<anonymous>)
    at __awaiter (./node_modules/@ethersproject/providers/lib/etherscan-provider.js:19:12)
    at BscscanProvider.EtherscanProvider.perform (./node_modules/@ethersproject/providers/lib/etherscan-provider.js:304:16) {
  reason: 'unsupported topic count',
  code: 'UNSUPPORTED_OPERATION',

This happens because tokenContract.filters.Transfer(address); returns an object where len(topics) > 1 which fails the check at EtherscanProvider.perform().

How can I go around this? Is there another way to list historic events?

Thanks!

Used dependencies:

  "dependencies": {
    "@ethers-ancillary/bsc": "^0.0.2",
    "ethers": "^5.4.6",
    "human-standard-token-abi": "^2.0.0",
    "web3": "^1.5.2",
    "web3-eth": "^1.5.2",
    "web3-utils": "^1.5.2"
  }

[zemse]

It seems you're using EtherscanProvider, it does not support topics more than one (code).

// this filter will not work with etherscan provider
var filter = tokenContract.filters.Transfer(address); // makes two topics: topic0 is Transfer and topic1 is address

// this filter can work
var filter = tokenContract.filters.Transfer(); // makes single topic: topic0 is Transfer