Fix fast 404 settings for private image files

That sounds like a reasonable thing to add to the documentation. Feel free to edit the page -- it is part of the Community Documentation. Moving this to the Documentation issue queue in case someone else wants to work on it.

Hm. Yeah, maybe it should be added to the settings.php file... feel free to move this back to Drupal Core. If you do, set the version to 8.0.x please, since our policy is to fix API documentation in Drupal 8 first, then backport to D7.

There we go...

If we open this discussion, I think it would be great to evaluate if it should be only in the settings file as documentation or by default be added to the path exclusions.

+1 to having the private file system added by default to the path exclusions.

A note in the docblock comment about the private file system would help as well.

It took me a very long time today to work out why my images weren't showing after I enabled the private file system. Everything worked fine on the stage server, but on the live server I was getting 404s.

Until I came across this page I wasn't aware of fast 404, now I guess I've learned my lesson :), but having the private file system excluded by default seems like a "sane default" to me. (Unless there are downsides I haven't considered yet).

@jelo --- with pleasure! Here's the patch.

I agree that documenting the issue is a good minimum step.

Docs look great! However I think we should really consider adding this to the defaults too?

In which case we should move this to the "base system" component as it is not just docs.

That seems like a good course of action to me, thanks!

Hi, sorry it took a while to get round to this. Here is the patch: I rewrote the docblock comment slightly as well.

This looks good to me, thanks! However the suggestions in #12 are not all there, and they seem like good additions to the documentation?

However the suggestions in #12 are not all there

Well, I re-wrote the suggestion in #12 slightly, so that it includes the sentence:
"The default pattern provided below also excludes the private file system."

For me, that covers the intention in #12. I made it a separate sentence because I thought that would be easier to read. It also makes it easier to understand that there are two parts to the exclusion - firstly for image styles, then secondly for the private file system.

 * The options below return a simple, fast 404 page for URLs matching a
 * specific pattern:
 * - $conf['system.performance']['fast_404']['exclude_paths']: A regular
 *   expression to match paths to exclude, such as images generated by image
 *   styles, or dynamically-resized images. The default pattern provided below
 *   also excludes the private file system. If you need to add more paths, you
 *   can add '|path' to the expression.

...

# $config['system.performance']['fast_404']['exclude_paths'] = '/\/(?:styles)|(?:system\/files)\//';

Oh, right! Sorry about that. Must have been Monday. I think this is good then!

Committed 6475b82 and pushed to 8.0.x. Thanks!

Here's the Drupal 7 backport.

Thanks! Yes, backporting this seems reasonable.

Hm, so as far as I can see this is only needed by sites that put the drupal_fast_404() line in settings.php. For other sites, the current setting would actually be preferable and more performant.

However, we already excludes 'styles' for all sites, and if you're using private files the performance gain from fast 404 is less important anyway, so yeah, let's do this and then maybe see if we can follow up with another issue to prevent Drupal from excluding anything except when drupal_fast_404() is actually called from settings.php.

Committed to 7.x - thanks!

Created a new issue as described above.