hook_views_data_alter is not fully documented

Still outstanding AFAICT - http://views.doc.logrus.com/

Here is a basic first version.

but this time.

I got clued into this hook from #372994: Ability to INNER JOIN to node for a specific field and went searching for docs and found this post.

Things I was looking for when looking for this documentation:

1. What's in that $data array so I don't have to print_r() it to find out?
2. When does this hook fire?
3. Why should I generally use it?
4. (my specific question) How can I change a join type?

I don't really know that any of those questions were answered by the current documentation.

In the examples, it would be nice to use something a bit more "real world" to give people a clue on what to do with this hook. If I end up figuring this out at all, I'll post back with an alternative patch, but please don't wait for me. ;)

'Riding a bit sidecar' to @webchick, I don't have a huge demand for making INNER JOINs on a specific field due to the low priority of my current task – but if I could do it, it might help the way I do many other things. If anyone can post answers to her 4 questions above, that would be very helpful

A few answers:

> 3. Why should I generally use it?

If another module has defined the table and you want to add a field.
Eg, your module provides a snazzy field on users. But {users} is already defined by Views core on behalf of user module. So you can't define your field in hook_views_data, you have to use this hook and add to the existing user key.

> 1. What's in that $data array so I don't have to print_r() it to find out?

Whatever modules put into it in hook_views_data. Same structure.

subscribing

I am wondering if anyone can explain why using an else if

function contains_argument_views_data_alter(&$data){
	foreach ($data as $table_name => $table){
		if (preg_match('/^profile_values/',$table_name)){
			if ($data[$table_name]['value']['argument']['handler'] == 'views_handler_argument_string'){
				$data[$table_name]['value']['argument']['handler'] = 'contains_argument_handler_argument_string_contains';
			} else if ($data[$table_name]['value']['filter']['handler'] == 'views_handler_filter_in_operator' || 
			  $data[$table_name]['value']['filter']['handler'] == 'views_handler_filter_profile_selection'){
				$data[$table_name]['value']['filter']['handler'] = 'contains_argument_handler_filter_taxonomy_profile_selection';
			} 
		}
	}
}

doesn't work, but if I separate it into 2 ifs...

function contains_argument_views_data_alter(&$data){
	foreach ($data as $table_name => $table){
		if (preg_match('/^profile_values/',$table_name)){
			if ($data[$table_name]['value']['argument']['handler'] == 'views_handler_argument_string'){
				$data[$table_name]['value']['argument']['handler'] = 'contains_argument_handler_argument_string_contains';
			} 
			if ($data[$table_name]['value']['filter']['handler'] == 'views_handler_filter_in_operator' || 
			  $data[$table_name]['value']['filter']['handler'] == 'views_handler_filter_profile_selection'){
				$data[$table_name]['value']['filter']['handler'] = 'contains_argument_handler_filter_taxonomy_profile_selection';
			} 
		}
	}
}

If works perfectly?

I spent a couple hours debugging this before I tried this on a whim. Maybe I missed a piece of documentation?!

While I agree that answers to webchick's questions would be nice enhancements, dereine's Patch in #3 provides the minimum needed to make use of this hook. There's no reason to wait for 'perfect' documentation when we've got 'good enough' sitting here waiting to be committed, and *nothing* in docs.php currently.

Moving this back to an active status; webchick's questions need answering, and nobody looks at stuff in 'needs work' :)

Looks like this still isn't documented, almost a year later. Having this documented would have definitely saved me some time.

The page http://api.drupal.org/api/views/views.api.php/function/hook_views_data_a... exists; the URL you gave doesn't ;)

It could still do with the $data array param being documented though.

Does this makes it a bit easier to understand?

The @see is redundant, I think this is enough.

Well, then I think its just the URL itself. The @see is already two lines below it, and doxygen needs it to be there.

It's in! Thanks for the patch.