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gateway: clarify Last-Modified #470
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- No matter if TTL value is known or not, implementations SHOULD always | ||
send a [`Last-Modified`](#last-modified-response-header) header with the timestamp of the record resolution. | ||
- Implementations MAY also place an lower bound of 1 minute to avoid excessive lookups. | ||
- If TTL value is unknown, implementations MAY not send a `Cache-Control` |
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May not?
- If TTL value is unknown, implementations MAY not send a `Cache-Control` | |
- If TTL value is unknown, implementations MAY send a `Cache-Control` |
When `Cache-Control` is not present, `Last-Modified` value also acts as a hint | ||
for web browsers in a process called "Calculating Heuristic Freshness" | ||
(Section 4.2.2 of :cite[rfc9111]). Each browser uses different heuristic, | ||
making this an inferior, non-deterministic caching strategy. |
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This is much more helpful for me.
- No matter if TTL value is known or not, implementations SHOULD always | ||
send a [`Last-Modified`](#last-modified-response-header) header with the timestamp of the record resolution. | ||
- Implementations MAY also place an lower bound of 1 minute to avoid excessive lookups. | ||
- If TTL value is unknown, implementations MAY not send a `Cache-Control` |
There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
May not?
- If TTL value is unknown, implementations MAY not send a `Cache-Control` | |
- If TTL value is unknown, implementations MAY send a `Cache-Control` |
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TODO: include information about optional modtime from UnixFS 1.5 (ipfs/boxo#659) and what takes priority on IPNS (modtime form dag-pb or ipns name resolution time)
Closes #467 by updating
Last-Modified
section.We forgot to do that as part of TTL cleanup, and that created contradiction reported by @SgtPooki (thx!)