BalanceChecker (go-balance)

Contract

The BalanceChecker contract allows the balances of multiple tokens for multiple addresses to be read with a single eth_call instead of several.

Within practical limits on the number of tokens and number of users specified, this can be significantly more effective than multiple individual balanceOf calls.

This contract includes a modification that allows ether balance to be read as well, by specifying the token address at a given position in the tokens array as the null address (address(0)).

interface BalanceChecker {
    function balances(
        address[] calldata users,
        address[] calldata tokens,
    )
        external
        view
        returns (uint256[] memory)
}

Library

Contained is the go package go-balance which includes go bindings and a simple abstraction around the BalanceChecker contract.

Install the package with:

go get -u github.com/hrharder/go-balance

For usage, see the included example.

Deployments

Known deployments of BalanceCheckers are listed below.

ChainID	Address	Date
1	0x46b5D094bDa9714abF2d90Dd692EcE546b00d9C5	2020-11-25

Notes

• Credit to Steve Marx (@smarx) for the Solidity.
• Re-generate the contract bindings as needed with go generate ./... (from the package root).