Gravatar Shouldn't Use images/blank.gif

[miqrogroove]

There is a very subtle flow-of-control error in pluggable.php:

	elseif ( 'blank' == $default )
		$default = includes_url('images/blank.gif');

This makes sense when $email has no value, because it will cause the local blank.gif file to be displayed. However...

When $email is not empty, this function is causing the gravatar.com server to make a proxy request to the blank.gif file and display the local file through a remote request. This is not the intended behavior. When the $email value is present, the Gravatar request should simply contain "&d=blank" to get a blank image.

[SergeyBiryukov]

Related: #21195

[Viper007Bond]

I think you should just do this:

elseif ( empty($email) && 'blank' == $default )

It's cleaner and more consistent with the existing code.

[Viper007Bond]

Simple fix

[miqrogroove]

Yes... somewhat related. However, this bug patch is ready to commit and shouldn't wait on new features.

Viper007Bond: Your code is not logically equivalent to mine. Please explain why you would make that additional change?

[Viper007Bond]

The fix plus a fix to allow ​https:// default image URLs as well as bringing the whole function up to modern coding standards

[Viper007Bond]

Replying to miqrogroove:

Viper007Bond: Your code is not logically equivalent to mine. Please explain why you would make that additional change?

Good catch. My patches should be disregarded.

The whole logic on that block is messy. I'm tempted to say we replace it with a cleaner switch and two ifs.

[miqrogroove]

I'm still in favor of the original patch if we can get it into beta. I wouldn't attempt a re-write for 3.5 at this point.

[nacin]

This is particularly timely because of ​http://blog.gravatar.com/2012/10/09/default-image-changes/, which was a change to the Gravatar service about a month ago that could affect the usage of blank.gif. Because of that, moving to 3.5.

[SergeyBiryukov]

miqro-blank-gravatars.diff​ makes sense to me.

22354.patch​ is a simplified version without reformatting the block.

[miqrogroove]

Thanks nacin. Do you want a more involved patch for this? In addition to the concerns from above, I just noticed on ​http://en.gravatar.com/site/implement/images/ that query strings are disallowed on default images now.

Sergey, yours is fine too.

[miqrogroove]

Testing shows query strings are still allowed within the d= variable. Disregard that.

[nacin]

In 22566:

Pass 'blank' to Gravatar rather than sending blank.gif for Gravatar to proxy. props miqrogroove, fixes #22354.

[miqrogroove]

Cool. Thanks everyone!