Дослідження з перевіркою джерел: Binance Onchainpay B402 Request

Decision Matrix

Source Map

• Binance Developer Docs: OnchainPay B402 API Request Signing (binance-b402-signing)
• Binance Developer Docs: Binance Developer Documentation (binance-developer-intro)
• Binance Developer Docs: Binance Pay Merchant API Specification Common Rules (binance-pay-common)

Control Notes

1. Key custody

Key custody is the decision point where public documentation must become an operating rule. In this package, it means request signatures depend on private-key control. The practical action is to store signing material outside source code and screenshots. The unresolved edge is merchant portal recovery process, so the article keeps that edge explicit instead of turning it into a reward claim, licensing claim, approval claim, recovery guarantee, price implication, settlement guarantee or platform ranking.

2. Serialization

Serialization is the decision point where public documentation must become an operating rule. In this package, it means signature verification can fail if body bytes change. The practical action is to serialize JSON once and sign the exact submitted string. The unresolved edge is middleware reformatting, so the article keeps that edge explicit instead of turning it into a reward claim, licensing claim, approval claim, recovery guarantee, price implication, settlement guarantee or platform ranking.

The operating test is also narrow. A public page can prove public wording.

3. Timestamp

Timestamp is the decision point where public documentation must become an operating rule. In this package, it means timestamp freshness protects requests from replay. The practical action is to sync clocks and alert on skew before retries. The unresolved edge is cross-region failover drift, so the article keeps that edge explicit instead of turning it into a reward claim, licensing claim, approval claim, recovery guarantee, price implication, settlement guarantee or platform ranking.

The operating test is also narrow. A public page can prove public wording.

4. Verify call

Verify call is the decision point where public documentation must become an operating rule. In this package, it means payment verification should be an explicit signed readback. The practical action is to record verification result before fulfillment. The unresolved edge is temporary upstream failure, so the article keeps that edge explicit instead of turning it into a reward claim, licensing claim, approval claim, recovery guarantee, price implication, settlement guarantee or platform ranking.

The operating test is also narrow. A public page can prove public wording.

5. Settle call

Settle call is the decision point where public documentation must become an operating rule. In this package, it means settlement evidence should be separated from payment presentation. The practical action is to write a non-secret settlement record. The unresolved edge is provider-side exception handling, so the article keeps that edge explicit instead of turning it into a reward claim, licensing claim, approval claim, recovery guarantee, price implication, settlement guarantee or platform ranking.

The operating test is also narrow. A public page can prove public wording.

6. Retry logic

Retry logic is the decision point where public documentation must become an operating rule. In this package, it means retries can duplicate signed requests if idempotency is absent. The practical action is to use deterministic request IDs and reconcile before retrying. The unresolved edge is unknown duplicate effects, so the article keeps that edge explicit instead of turning it into a reward claim, licensing claim, approval claim, recovery guarantee, price implication, settlement guarantee or platform ranking.

The operating test is also narrow. A public page can prove public wording.

7. Stop rule

Stop rule is the decision point where public documentation must become an operating rule. In this package, it means stop when signature, timestamp, verify or settle evidence is inconsistent. The practical action is to hold payment automation until readback matches. The unresolved edge is support-only settlement dispute detail, so the article keeps that edge explicit instead of turning it into a reward claim, licensing claim, approval claim, recovery guarantee, price implication, settlement guarantee or platform ranking.

The operating test is also narrow. A public page can prove public wording.

Known Unknowns

• merchant portal recovery process
• middleware reformatting
• cross-region failover drift
• temporary upstream failure
• provider-side exception handling
• unknown duplicate effects
• support-only settlement dispute detail

Practical Takeaway

Binance OnchainPay B402 integration should start with signing discipline before any payment workflow is treated as production-ready. Current Binance developer documentation describes RSA-SHA256 request signing, public-key onboarding, timestamp headers, client identity headers and troubleshooting guidance for signature failures. It also frames verify and settle calls as signed API interactions whose body bytes and timestamp must match the signature input. The decision outcome is to define key custody, exact JSON serialization, timestamp tolerance, verification readback, settlement evidence and retry idempotency before connecting B402 payment handling to fulfillment or accounting. The article stops at the evidence boundary. It helps the reader decide what to inspect next without converting public documentation into a promise that a private account, wallet, callback, policy framework, settlement route or liquidity position will work under every future condition.