Question: `get_table_rows` from Checksum256 as secondary index

[Denis]

Question

What is the best way to query a table row with Checksum256 as secondary index?

JS Code example

https://codesandbox.io/p/sandbox/snowy-sunset-lrqqmm?file=%2Findex.js

Smart Contract (EOS EVM)

struct [[eosio::table]] [[eosio::contract("evm_contract")]] account {
    uint64_t    id;
    bytes       eth_address;
    uint64_t    nonce;
    bytes       balance;
    std::optional<uint64_t>       code_id;

    uint64_t primary_key()const { return id; }

    checksum256 by_eth_address()const { 
        return make_key(eth_address);
    }

    uint256be get_balance()const {
        uint256be res;
        std::copy(balance.begin(), balance.end(), res.bytes);
        return res;
    }

    EOSLIB_SERIALIZE(account, (id)(eth_address)(nonce)(balance)(code_id));
};

Works with eosc

$ eosc -u https://jungle4.api.eosnation.io get table eosio.evm eosio.evm account --lower-bound aa2F34E41B397aD905e2f48059338522D05CA534 --upper-bound aa2F34E41B397aD905e2f48059338522D05CA534 --key-type sha256 --index 2

{
  "more": false,
  "rows": [
    {
      "id": 6241,
      "eth_address": "aa2f34e41b397ad905e2f48059338522d05ca534",
      "nonce": 10,
      "balance": "0000000000000000000000000000000000000000000000053221ae6683fe8801",
      "code_id": null
    }
  ]
}

[Aaron Cox]

It looks like it'll take in the string you initially provided, and then as long as you specify the key_type value it'll handle everything properly. I think behind the scenes its actually converting everything back to a string anyways, since that's ultimately what the API endpoint is expecting for the query.

Functional:

https://codesandbox.io/p/sandbox/snowy-sunset-lrqqmm?file=%2Findex.js

Code in the event the sandbox goes away:

import { APIClient } from "@wharfkit/session";
import fetch from "node-fetch";

export const rpc = new APIClient({
  url: "https://jungle4.api.eosnation.io",
  fetch,
});

export function get_balance(address) {
  address = address.replace("0x", "");
  return rpc.v1.chain.get_table_rows({
    code: "eosio.evm",
    scope: "eosio.evm",
    table: "account",
    index_position: "secondary",
    lower_bound: address,
    upper_bound: address,
    key_type: "sha256",
    json: true,
    limit: 1,
  });
}

const address = "0xaa2F34E41B397aD905e2f48059338522D05CA534";
get_balance(address).then((response) => console.log(response));

[Denis]

Great! 👍 works using key_type: "sha256"

However, encountering a Types issue by providing string as lower_bound & upper_bound

Patched for now by setting as any

[Denis]

Will close this issue, @aaroncox can open another for the type specific issue

[Denis]

For future reference, this is the Typescript code to get EVM balance using Wharfkit

export async function get_balance(address: any) {
    address = address.replace("0x", "");
    const response = await rpc.v1.chain.get_table_rows({
        code: "eosio.evm",
        scope: "eosio.evm",
        table: "account",
        index_position: "secondary",
        lower_bound: address,
        upper_bound: address,
        json: true,
        limit: 1,
        key_type: "sha256",
    })
    if (response.rows.length === 0) return 0.0
    return parseInt(response.rows[0].balance, 16) / 10 ** 18;
}