[documentation] [Documentation bug] Update needed to node_example.module

[pwolanin]

Issue status update for 
http://drupal.org/node/84602
Post a follow up: 
http://drupal.org/project/comments/add/84602

 Project:      Documentation
 Version:      <none>
 Component:    Developer Guide
 Category:     bug reports
 Priority:     normal
 Assigned to:  Anonymous
 Reported by:  plumbley
 Updated by:   pwolanin
 Status:       active

I think form_set_value *is* needed to chage a vlue at the validate sage,
as opposed to being able to directly change the node in 4.6.  I was just
try to help someone figure this out recently:
http://drupal.org/node/83130




pwolanin



Previous comments:
------------------------------------------------------------------------

Sun, 17 Sep 2006 08:06:24 +0000 : plumbley

Current CVS documentation for hook_example_validate() includes the
example
<?php
function node_example_validate(&$node) {
  [ ... if ($node->quantity) { ]
    // Let an empty field mean "zero."
    $node->quantity = 0;
  }
} 
?>
But since 4.7 it looks like any changes to $node made in hook_validate
are ignored. E.g. in modules/node/node.module we have
<?php
function node_validate($node, $form = array()) {
  ...
  node_invoke($node, 'validate', $form);
  node_invoke_nodeapi($node, 'validate', $form);
}
?>
which is pass-by-value rather than pass-by-reference. So although
node_invoke() passes by reference, no changes to $node can "escape" out
of node_validate.


I'm guessing this is by design, but if so the documentation should say
what to do instead. E.g. I *think* form_set_value() should now be used,
but its a bit non-obvious. For example, I used something similar to the
following elsewhere (in 4.7):
<?php
  form_set_value(array('#parents' => array('quantity')), 0);
?>
Is this now the recommended route to change nodes? (or not?). Mark.


PS Looks like the change to validation operation in 4.7 also caused
problems for node_import, which ideally should be able to validate a
node without requiring a form to be present, so a documentation update
might help getting validation working there too.




------------------------------------------------------------------------

Sun, 17 Sep 2006 19:13:44 +0000 : plumbley

Renamed now I finally found out what I probably should have found much
earlier about the 4.7 submit process (see e.g.
http://drupal.org/node/22218#node_hook_order). Please ignore my previous
rubbish about form_set_value().


It looks like node_example.module as appears in 4.7 at
http://api.drupal.org/api/4.7/file/developer/examples/node_example.modul...
and CVS at
http://api.drupal.org/api/HEAD/file/developer/examples/node_example.modu...
actually applies to 4.6, and is in need of update.


I'm still a bit new here but perhaps hook_validate() should now be
pass-by-value and read e.g.:
<?php
function node_example_validate($node) {
  // If the field is set, it must be a number
  if (!empty($node->quantity) && !is_numeric($node->quantity)) {
   
form_set_error('quantity', t('The quantity must be a number.'));
  }
}
?>
with a new hook_submit() which performs the modification
<?php
function node_example_submit(&$node) {
  if (empty($node->quantity)) {
    // Let an empty field mean "zero."
    $node->quantity = 0;
  }
}
?>
If its too fiddly to fix for the moment, perhaps just a note to say
"node_example.module applies to 4.6, see
http://api.drupal.org/api/4.7/file/developer/hooks/node.php for up to
date documentation" in the meantime? Mark.