Change values of nested fields with entity_metadata_wrapper

Question

The background of this question is that I'm trying to migrate data from Drupal 6 Imagefield Extended to Drupal 7 File Entity (with File Entity Inline). See also https://www.drupal.org/node/974888

First I tried to understand how entities work and how they can be extracted and manipulated using Entity Metadata Wrappers. That seems to work ok, for example, I can get the values of my imagefield like this:

$nid = 103025;
$node_wrapper = entity_metadata_wrapper('node', $nid);
$images = $node_wrapper->field_image->value();

And it seems that I could change the values of the images with something like this:

// Do something with $images
$node_wrapper->field_image->set($images);
$node_wrapper->revision->set(1);
$node_wrapper->save();

(For some reason it's not saving the values for the node in my case, but that's another question.)

My problem now is that I have nested fields, i.e. the imagefield has "subfields" for the source and license (that I had added in Drupal 6 using Imagefield Extended). I do get the values of those nested fields in $images - but only in the typical array with $images[und][0]['value'] and $images[und][0]['safe_value']. But there seems to be no way to get those values through the wrapper, for example like

$node_wrapper->field_image->field_source->value();
$node_wrapper->field_image->value()->field_source->value();

Now I have been trying for hours to figure out how I can change (or populate) those (sub) fields and then save the entire node, but to no avail.

I'm also wondering if it's necessary to do this on a node level as files are also entities, but it seems that there is nothing like entity_metadata_wrapper('file', $fid);.

I'd appreciate any hint that could point me in the right direction because the search has been kind of exhausting.

Answer 1

Using what Clive mentioned and with the hint eikes provided, this seems to be a way to accomplish what I want:

$nid = 108501;
$node_wrapper = entity_metadata_wrapper('node', $nid);

for ($i = 0; $i < count($node_wrapper->field_image->value()); $i++) {
  $node_wrapper->field_image[$i]->file->field_source->set('NEW SOURCE');
  $node_wrapper->field_image[$i]->file->field_license->set('NEW LICENSE');
  $node_wrapper->field_image[$i]->file->save();
}

// Just for dev: Check if the values have been saved
$node_wrapper = entity_metadata_wrapper('node', $nid);
dsm($node_wrapper->field_bild->value());

Erroneously I used the save() call on the whole node wrapper, but as files are their own entities, the call needs to be on the file, as eikes suggested.

Additionally, I noticed that calling $node_wrapper = entity_metadata_wrapper('node', $nid); after the above code doesn't reflect the changes (for checking). It seems I need to reload the entity first.

Thanks a lot to both of you!

Answer 2

This is my solution to access and update 2 nested levels deep on unlimited values on field collections fields

  function set_descuentos_pagos_action($nid) {
  // $raw_node = node_load($nid);  AVOID THIS
  $node = entity_metadata_wrapper('node', $nid);
  // dpm($node->getPropertyInfo());
  // dpm($node);
  $raw_ana = $node->field_ana->value();
  // dpm($raw_ana);
  $num_cotizaciones = count($raw_ana);

  // $i ES EL ITEM DE  CADA COTIZACION
  for ($i=0 ; $i < $num_cotizaciones  ; $i++ ) {
    
    $ana[$i] = entity_metadata_wrapper('field_collection_item', $raw_ana[$i]);
    $fp = $ana[$i]->field_m_fc_pago_texto->value();
    if($fp == 'Trimestral'){
      // get values from parent field collection
      $prima_descuento[$i] = $ana[$i]->field_m_fc_prima_neta_descuento->value();
      $prima_original[$i] = $ana[$i]->field_m_fc_prima_neta->value();
      $factor[$i] = $prima_descuento[$i] / $prima_original[$i];

      // get child field collection
      $raw_recibos = $ana[$i]->field_m_fc_recibo->value();
      $num_recibos[$i] = count($raw_recibos);

      // $j SON LOS PAGOS DE LA ITERACION $i
      for ($j=0; $j < $num_recibos[$i]; $j++) {

        // get current child field collection object
        $value[$j] = $ana[$i]->field_m_fc_recibo[$j]->value();

        // $pago[$j] ES EL PAGO OBJETO
        $pago[$j] = entity_metadata_wrapper('field_collection_item', $value[$j]);
         // dpm($pago[$j]->value());
         // get field value, set value on other field
         $prima = $pago[$j]->field_m_fc_prima_total->value();
         $nuevo_valor = $prima * $factor[$i];
         $pago[$j]->field_m_fc_prima_total_descuento->set($nuevo_valor);
         $pago[$j]->save();
      }

    }
  }

} // end  set_descuento_pagos_cotizacion