Module payment 

Payment verification system for ant-node.

This module implements the payment verification strategy:

1. Check LRU cache for already-verified data
2. Require and verify EVM/Arbitrum payment for new data

Default Policy

Production nodes require payment by default.

• EVM verification is always on — there is no way to disable it
• For unit tests, pre-populate the cache via PaymentVerifier::cache_insert()

Architecture

PUT request received
       │
       ▼
┌─────────────────────┐
│ Check LRU cache     │
└─────────┬───────────┘
          │
   ┌──────┴──────┐
   │             │
  HIT          MISS
   │             │
   ▼             ▼
Store (paid)   Require EVM payment

Payment Flow

All new data requires EVM payment:

1. Client requests a quote from the node
2. Node generates PaymentQuote with ML-DSA-65 signature
3. Client pays on Arbitrum via PaymentVault.payForQuotes()
4. Client sends PUT with ProofOfPayment
5. Node verifies on-chain payment and stores data

Re-exports

pub use metrics::QuotingMetricsTracker;

pub use pricing::calculate_price;

pub use proof::deserialize_merkle_proof;

pub use proof::deserialize_proof;

pub use proof::detect_proof_type;

pub use proof::serialize_merkle_proof;

pub use proof::serialize_single_node_proof;

pub use proof::PaymentProof;

pub use proof::ProofType;

pub use quote::verify_merkle_candidate_signature;

pub use quote::verify_quote_content;

pub use quote::wire_ml_dsa_signer;

pub use quote::QuoteGenerator;

pub use quote::XorName;

pub use single_node::SingleNodePayment;

pub use wallet::is_valid_address;

pub use wallet::parse_rewards_address;

pub use wallet::WalletConfig;

Modules

metrics

Quoting metrics tracking for ant-node.

pricing

Local fullness-based pricing algorithm for ant-node.

proof

Payment proof wrapper that includes transaction hashes.

quote

Payment quote generation for ant-node.

single_node

SingleNode payment mode implementation for ant-node.

wallet

EVM wallet management for receiving payments.

Structs

CacheStats

Cache statistics for monitoring.

EvmVerifierConfig

Configuration for EVM payment verification.

PaymentVerifier

Main payment verifier for ant-node.

PaymentVerifierConfig

Configuration for the payment verifier.

VerifiedCache

LRU cache for verified XorName values.

Enums

PaymentStatus

Status returned by payment verification.

Constants

MAX_PAYMENT_PROOF_SIZE_BYTES

Maximum allowed size for a payment proof in bytes (256 KB).

MIN_PAYMENT_PROOF_SIZE_BYTES

Minimum allowed size for a payment proof in bytes.