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Documentation Index

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Overview

PaymentIndexRecorderHook indexes payments by payer and receiver and stores the full PaymentInfo struct keyed by paymentInfoHash. Wire it into AUTHORIZE_POST_ACTION_HOOK on a HookCombinator (or directly when authorize is the only hook slot you use) so each new authorization registers itself for on-chain lookups.

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When to use

  • You need on-chain payment lookups without a subgraph
  • Other contracts need to read the full PaymentInfo for a hash, or page through every payment by payer / receiver
  • You want a single chain-singleton index that aggregates across every operator routing through HookCombinator
Skip when: you’re using a subgraph for payment queries, since the subgraph can derive indexes from events without the on-chain gas cost.

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State

mapping(bytes32 paymentInfoHash => AuthCaptureEscrow.PaymentInfo) private paymentInfoStore;
mapping(address payer    => mapping(uint256 index => bytes32 hash)) private payerPayments;
mapping(address payer    => uint256 count)                        public  payerPaymentCount;
mapping(address receiver => mapping(uint256 index => bytes32 hash)) private receiverPayments;
mapping(address receiver => uint256 count)                        public  receiverPaymentCount;

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Methods

function run(
    AuthCaptureEscrow.PaymentInfo calldata paymentInfo,
    uint256 /* amount */,
    address /* caller */,
    bytes calldata /* data */
) external {
    bytes32 hash = escrow.getHash(paymentInfo);
    paymentInfoStore[hash] = paymentInfo;
    payerPayments[paymentInfo.payer][payerPaymentCount[paymentInfo.payer]++] = hash;
    receiverPayments[paymentInfo.receiver][receiverPaymentCount[paymentInfo.receiver]++] = hash;
}

function getPaymentInfo(
    bytes32 paymentInfoHash
) external view returns (AuthCaptureEscrow.PaymentInfo memory);

function getPayerPayments(
    address payer,
    uint256 offset,
    uint256 count
) external view returns (AuthCaptureEscrow.PaymentInfo[] memory, uint256 total);

function getReceiverPayments(
    address receiver,
    uint256 offset,
    uint256 count
) external view returns (AuthCaptureEscrow.PaymentInfo[] memory, uint256 total);
amount, caller, and data are unused; they exist to satisfy IHook.run.

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Querying

const info = await paymentIndex.read.getPaymentInfo([paymentInfoHash])

const [payerInfos, total] = await paymentIndex.read.getPayerPayments([
  payer,
  0n,
  10n,
])

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Gas

Cost: ~175k gas per authorization (payer index + receiver index + full PaymentInfo SSTORE).

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Next Steps

HookCombinator

Combine with other hooks in a single slot.

Hooks Overview

Compare recording strategies.