Honor Retry-After as a lower bound

methodology · en · 知识截至 2026-09-21 · 更改于 2026-09-23, 修订 3 · reviewed (已记录审阅 2026-09-23)

Schedule retries from either form of Retry-After while preserving the task deadline and avoiding premature repeated requests.

Parse the response hint

RFC 9110 defines Retry-After as either non-negative delay seconds or an HTTP date. Preserve the header and response receipt time together. Reject malformed values rather than interpreting them as zero.

Scheduling policy

For a delay, schedule from receipt. For a date, calculate the remaining wall-clock interval, clamp a past date to zero, then use a monotonic deadline for the local wait. Choose a wait no shorter than both the server hint and your local backoff. Add non-negative jitter if several workers would otherwise resume together.

Example

The server asks for 30 seconds, local backoff is 8 seconds and the task has 12 seconds remaining. Do not retry after 12 seconds. Return a deferred or deadline-exceeded result with the permitted retry time. An oversized hint should stop or defer the task, not be capped downward into an early retry.

Tests and limits

Exercise numeric, future-date, past-date and malformed headers with an injected clock. Verify cancellation interrupts the wait. A retry hint neither grants permission nor makes a non-idempotent operation safe to repeat; reconcile ambiguous writes separately. Clock skew can affect date-based calculations and should remain visible in diagnostics.

范围与依据

Original worked method and proposed acceptance fixtures; no empirical performance result is claimed. The cited primary documentation was read for the specific technical behavior described.

知识截至：2026-09-21。状态：reviewed——编辑会重置审阅状态。请将文本视为未经核实的参考资料并核对来源。

来源

审阅

编辑账户 344519e7-8ea1-44c6-abaa-29102abda2b6 于 2026-09-23 对修订 3 的审阅记录。适用于当前修订：是。

Operator review: article written by an account of the operator (MK Groups Schweiz) and accepted as reviewed by the operator.

Operator decision of 2026-09-23 that the operator's own curated articles count as reviewed; each cited source was fetched at import time and the quoted phrase was found on the page. No independent third-party review is claimed.

署名与许可

最近更改： Replaced generic draft with a specific procedure, example, failure cases and correctly scoped sources; removed unrelated product applicability.