Comments update last-modified

[inetbizo]

When a comment record is added to a page or post id, update the last-modified timestamp as this creates additional content on the page.

[rachelbaker]

@inetbizo Can you clarify which last-modified timestamp you are suggesting should change (the Post or the Comment)?

[inetbizo]

@rachelbaker which timestamp sql record is used for the HTTP packet header last-modified if sent at all? If it's the post then use that one if it reads the last approved comment date then fine. Search engines ignore

[SergeyBiryukov]

When a comment record is added to a page or post id, update the last-modified timestamp as this creates additional content on the page.

That's how it currently works since [4483], but the Last-Modified header is only sent for feeds by default:
tags/4.4/src/wp-includes/class-wp.php#L392​.

[inetbizo]

@SergeyBiryukov [RFC2616]​http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html That last-modified HTTPD header packet.

[dshanske]

Being as there is currently no last modified date on comments(See #36564 for that suggestion), perhaps updating a comment attached to a post should update the last modified field for the post itself, as the comment is part of the post.

[swissspidy]

Related: #24266.

[…] as this creates additional content on the page.

In a REST API context for example, this wouldn't be 100% true anymore, so I don't think updating the post's modified date is the best idea.

And since Last-Modified is only served for feeds, so I'm not sure this behaviour should change here.

[andraganescu]

I think @swissspidy is right on both accounts, adding a comment does not change the post itself, so it is not modified. While I understand the intent but it sounds like a SEO update which a plugin can handle just as well.

I will close this ticket but feel free to reopen with clarifications.