Co-Authors Plus and wp_query

I’ve put together a document which hopefully explains this better. Let me know what you think of it, and whether you have any follow up questions I should answer with it.

That has solved it just beautifully. Thank you so much for your help with this, Daniel!

??

It’s been a while, but since this is relevant to the same conversation, I’d like to add a follow-up question: Is it possible, using this (or another) method, to display posts from a group of co-authors? Traditionally we might once have used something along the lines of author=1,2,3 but author_name doesn’t accept multiple values, as far as I can figure. Does that mean that since we are without the option of passing author ID values to WP_Query, there’s no way to specify multiple co-authors?

I though I was making some headway with these arguments, but I think they’re actually just returning everything.

$query_args = array(
	'orderby' => 'date',
	array(
		'relation' => 'OR',
		'author_name' => array('first-author','second-author')
	),
);

(Posted this before I realized the problem, haha.)

You’ll get the most mileage out of using a taxonomy query. Each author is a taxonomy term, and you can include multiple terms in your query.

I’m probably setting the cause back a bit by not being able to get the tax_query right (I’ve been trying it for a while), but I’ve definitely got something wrong here, as I can’t even get it to return results for a single co-author:

'tax_query' => array(
	array(
		'taxonomy' => 'author',
		'field' => 'slug',
		'terms' => 'first-author'
	)
)

This was where I began yesterday, but after referencing the previously-mentioned documentation (https://vip.wordpress.com/documentation/list-posts-by-a-co-author/), thought I was mistaken and needed to go back to author_name. There’s nothing like trying to piece together progress made eight months prior, huh?

The term slug can be prefixed with cap-. If you have access to the database, check to make sure that your author term doesn’t have that prefix.

Yes! Prefixing cap- to each of my co-authors’ slugs has done the trick, and I’m able to successfully include posts from a group of authors by using an array of cap- slugs. Thank you very much (as always), Daniel.

Hi!
I have a similar problem. If I call wp_query with a single author id, works only if is the first co-author. If the co-author is second wp_query is empty. If in post edit, i switch the co-authors, that last author id works.

@cristian Can you provide an example of the code you’re using?

$args = array ('post_type' => 'materii', 'posts_per_page' => -1, 'order' => 'ASC');
foreach($_POST as $key => $value) if($value!=NULL) $args[$key] = $value;
$wp_query = new WP_Query( $args );

and the $_POST[‘author’]={id}

Ok. Similar to above, you’ll want to write a taxonomy query because the second co-author is actually a term relation, not stored in post_author column.

Understood. I’ll try it. Thanks.