Incorrect Retry-After header value

[awlayton]

Prerequisites

• I have written a descriptive issue title
• I have searched existing issues to ensure the bug has not already been reported

Fastify version

4.17.0

Plugin version

8.0.0

Node.js version

20.2.0

Operating system

Linux

Operating system version (i.e. 20.04, 11.3, 10)

22.04.2

Description

It seems the value of the Retry-After header is expressed in milliseconds instead of seconds (or an http-date) as specified by RFC 9110.

Steps to Reproduce

@fastify/rate-limit options:

const options = {
  max: 5,
  timeWindow: '1 minute',
};

Headers on 429 response:

x-ratelimit-limit: 5
x-ratelimit-remaining: 0
x-ratelimit-reset: 58
retry-after: 60000

Expected Behavior

The value of Retry-After should be 60 (i.e., 1 minute in seconds), not 60000.

[mcollina]

Thanks for reporting! Would you like to send a Pull Request to address this issue? Remember to add unit tests.

[Uzlopak]

Probably issue is here

fastify-rate-limit/index.js

Line 249 in 6bf150a

const resetAfterTime = (params.enableDraftSpec) ? timeLeft : params.timeWindow

timeWindow is time in milliseconds but we should have a timeWindowInSeconds value were we have the timeWindow in seconds and use that.

[Uzlopak]

Created a PR #307