Example: Validator Balance Data
Verify data by using a Merkle Proof against a state root.
In this example, the contract has a reference to the Telepathy Light Client and uses the state root stored for a specific
slot. Using a Merkle Proof, you can then verify that the data provided is correct for the that
slot's state root.contract BeaconValidatorBalance {
uint256 public constant VALIDATOR_PUBKEY_GINDEX = 0;
uint256 public constant BALANCE_G_INDEX = 1;
address lightclient;
mapping(uint256 => bytes32) public indexToPubkey;
mapping(uint256 => mapping(uint256 => uint256)) public indexToSlotToBalance;
constructor(address _lightclient) {
lightclient = _lightclient;
}
function addIndexAndPubkey(
uint256 slot, uint256 index, bytes32 publicKey, bytes32[] memory proof
) public {
bytes32 headerRoot = ILightClient(lightclient).headers(slot);
bool isValidProof = SSZ.verifyMerkleBranch(
publicKey,
concatGIndex(VALIDATOR_PUBKEY_GINDEX, index),
proof,
headerRoot
);
require(isValidProof, "Invalid state root");
indexToPubkey[index] = publicKey;
}
function addBalanceAtSlot(uint256 slot, uint256 index, uint256 balance, bytes32[] memory proof) public {
bytes32 headerRoot = ILightClient(lightclient).headers(slot);
bool isValidProof = SSZ.verifyMerkleBranch(
bytes32(balance),
concatGIndex(BALANCE_G_INDEX, index),
proof,
headerRoot
);
require(isValidProof, "Invalid state root");
indexToSlotToBalance[index][slot] = balance;
}
}