is_uncacheable_request_method() should only allow certain request types

[raamdev]

Forked from #220 (comment), an issue where we forced Quick Cache to ignore certain types of requests to prevent the possibility of a blank page being cached.

Instead of ignoring certain requests, the is_uncacheable_request_method() should be changed to only allow the request types that we consider acceptable.

@jaswsinc writes:

I suggest that we change is_uncacheable_request_method()

Instead of us trying to weed out those which are unacceptable, let's allow only those which we know ARE acceptable. I noticed there are some obscure request methods that could still cause this issue. Such as: TRACK, DEBUG and PATCH. http://en.wikipedia.org/wiki/Hypertext_Transfer_Protocol#Request_methods

---

Support threads referencing this issue

• http://wordpress.org/support/topic/blank-page-again-fix-in-v140725-cant-help

[taninsammanee]

Hi @raamdev & Quick Cache team,

Any updates on this issue?

It is a critical/blocker blank page issue to us and we do not see it fixed in the latest release v140829 (https://wordpress.org/plugins/quick-cache/changelog/). Could you please let us know the target date to release this fix? We need it as soon as possible.

Regards,
Tanin Sammanee

[raamdev]

@taninsammanee Our current development cycle closed about a week ago, but this bug will be added as a priority item to the next development cycle, for a target release candidate within 3-4 weeks.

If you're interested in testing a beta release of Quick Cache before the next version comes out, please sign-up to be a beta tester here and you'll receive an email notification when a new release candidate is available.

[jaswrks]

Additional Work Needed Here...

Referencing this line of code in the pro version of Quick Cache.
https://github.com/websharks/quick-cache-pro/blob/000000-dev/quick-cache-pro/includes/advanced-cache.tpl.php#L907

---

Whenever we update is_uncacheable_request_method(), we also need to build a second method: is_post_put_delete(), which is still necessary (it was removed in the previous set of changes).

To clarify, the previous work on is_uncacheable_request_method() should have addressed this, but it didn't. It's OK for now, but whenever we come back to this issue, that needs to be another part of the work here. In short, maybe_postload_invalidate_when_logged_in() doesn't need to know if the request method is uncacheable, only that the current request method is POST, PUT or DELETE.

[jaswrks]

Assigning this to myself. I'll work on it this week.

[jaswrks]

@raamdev This has been resolved by the PRs I submitted earlier.

[raamdev]

@jaswsinc PRs have been reviewed and merged. Thank you very much! :)

[raamdev]

Next release changelog:

• Bug Fix: Fixed an issue with detecting cacheable requests that was, in rare instances, resulting in blank white pages for some site owners. See #279.

[carvax]

Im on Quick Cache pro Versión 141110 , and same bug :(

My site its on VPS 2Gb ram, 4 Cores and Nginx. is frustrating to see the white page

[raamdev]

@carvax A few questions:

• Are you seeing a blank cached page?
• Does this happen at a specific interval (e.g., once a day)?
• Does clearing the cache fix the problem?

[carvax]

Hi Ramm
-blank page appears when I save a post with new TAGS
-blank page appears only in dashboard when i make speciffic things like clic on save something new.
-Clearing the cache doesnt fix the problem.
-now I'm using the free version, it I have no problems, the problem appears only in the pro version

[raamdev]

-blank page appears when I save a post with new TAGS

Thank you. That's a separate issue from this one (which is related to is_uncacheable_request_method()--an entirely separate area of the plugin). I've opened a separate GitHub issue for you here: #372