Fix broken AJAX URLs

[carlalexander]

This is a fix for an issue with the rewrite rules for admin-ajax.php. You cannot create rewrite rules this way as this isn't how rewrite rules in WordPress work. (You can read more about it here.) These rewrite rules might work with Apache but only because they're added to the .htaccess file. They won't work with nginx.

Instead, the correct way to do this is to use the ajaxurl variable that WordPress puts at your disposition. I've edited amber.js to make use of it. I've also removed the rewrite rules. There was also a missing AJAX action for logcacheview which I added.

[jlicht]

(First, apologies for the merging/reverting of this pull request. Ideally we would reopen this pull request and update it as needed, but let's use it for discussion of this proposed change)

If I understand correctly, you're running Amber under nginx, and apache isn't present anywhere in the stack. This isn't actually a configuration we've tested, and it sounds like you needed to make some nginx configuration changes to make that possible. If you can share those changes, it would give us a leg up on testing and documenting that setup.

Thoughts on the specific changes in the pull request:

• ajaxurl variable is not available on the front-end of the site by default (unless another plugin has defined it), so we'll need to include surfacing that as part of this pull request.
• I believe we intentionally did not provide a privileged url for logcacheview, since it's never used on the admin site

@jerclarke

[carlalexander]

This isn't actually a configuration we've tested, and it sounds like you needed to make some nginx configuration changes to make that possible. If you can share those changes, it would give us a leg up on testing and documenting that setup.

I'm not sure I understand this. There's no configuration change to do on nginx. It's not how it works. You can read more about it here, but the main point is this:

Since Nginx does not have .htaccess-type capability and WordPress cannot automatically modify the server configuration for you, it cannot generate the rewrite rules for you.

This means that creating rewrite rules that only work if they are in an .htaccess file (this was the stack overflow question I linked to) won't work since WordPress can't modify the behaviour of nginx that way. The amber plugin must always point to admin-ajax.php to interact with AJAX. It cannot rely on rewrite rules like those.

I thought that ajaxurl was available in the frontend so that's my bad on that. So what we'd need is either output it manually as you describe. (Also mentioned here) I'm not sure what the preferred solution to this is, but that's one way of doing it.

As for the wp_ajax_amber_logcacheview hook, the issue was that, without this hook, Amber would not log views for logged in users. This was an issue because we still want Amber to log views if someone is logged in. So that's why this hook was added. We could add an option to revert this to the old behaviour while allowing us to continue log views with logged-in users. You also read more about it here.