tripal/tripal_feature/includes/tripal_feature.chado_node.inc

<?php 

/**
 * Implementation of hook_form
 * 
 * @param  $node
 * @param  $param
 * 
 * @return 
 *   Drupal form array
 *   
 * @ingroup tripal_feature
 */
function chado_feature_form($node, &$form_state) {

  $form = array();

  // Default values can come in the following ways:
  //
  // 1) as elements of the $node object.  This occurs when editing an existing feature
  // 2) in the $form_state['values'] array which occurs on a failed validation or
  //    ajax callbacks from non submit form elements
  // 3) in the $form_state['input'[ array which occurs on ajax callbacks from submit
  //    form elements and the form is being rebuilt
  //
  // set form field defaults
  $feature      = null;
  $feature_id   = null;
  $uniquename   = '';
  $fname        = '';
  $feature_type = '';
  $organism_id  = '';  
  $residues     = '';
  $is_obsolete  = '';
  $analyses     = '';
  $references   = '';
  $synonyms     = '';
  
  // if we are editing an existing node then the feature is already part of the node
  if (property_exists($node, 'feature')) {
    $feature = $node->feature;
    $feature = tripal_core_expand_chado_vars($feature, 'field', 'feature.residues');
    $feature_id   = $feature->feature_id;
    $uniquename   = $feature->uniquename;
    $fname        = $feature->name;
    $feature_type = $feature->type_id->name;
    $organism_id  = $feature->organism_id->organism_id;
    $residues     = $feature->residues;
    $is_obsolete  = $feature->is_obsolete;
    
    // get the synonyms from a previous post
    $synonyms = '';
    if(property_exists($node, 'synonyms')) {
      $synonyms = $node->synonyms;
    }
    
    // get synonyms from the database if we don't already have them
    if (!$synonyms) {
      $options = array('return_array' => 1);
      $feature = tripal_core_expand_chado_vars($feature, 'table', 'feature_synonym', $options);
      $feature_synonyms = $feature->feature_synonym;      
      foreach ($feature_synonyms as $index => $synonym) {
        $synonyms .= $synonym->synonym_id->name . "\n";
      }
    }
    // keep track of the feature id 
    $form['feature_id'] = array(
      '#type' => 'value',
      '#value' => $feature_id,
    );
  }
  // if we are re constructing the form from a failed validation or ajax callback
  // then use the $form_state['values'] values
  if (array_key_exists('values', $form_state)) {
    $uniquename   = $form_state['values']['uniquename'];
    $fname        = $form_state['values']['fname'];
    $feature_type = $form_state['values']['feature_type'];
    $organism_id  = $form_state['values']['organism_id'];
    $residues     = $form_state['values']['residues'];
    $is_obsolete  = $form_state['values']['is_obsolete'];
    $synonyms     = $form_state['values']['synonyms'];
  }
  // if we are re building the form from after submission (from ajax call) then
  // the values are in the $form_state['input'] array
  if (array_key_exists('input', $form_state) and !empty($form_state['input'])) {
    $uniquename   = $form_state['input']['uniquename'];
    $fname        = $form_state['input']['fname'];
    $feature_type = $form_state['input']['feature_type'];
    $organism_id  = $form_state['input']['organism_id'];
    $residues     = $form_state['input']['residues'];
    $is_obsolete  = array_key_exists('is_obsolete', $form_state['input']) ? $form_state['input']['is_obsolete'] : FALSE;
    $synonyms     = $form_state['input']['synonyms'];
  }

  $form['fname']= array(
    '#type' => 'textfield',
    '#title' => t('Feature Name'),
    '#required' => TRUE,
    '#default_value' => $fname,
    '#description' => t('Enter the name used by humans to refer to this feature.'),
    '#maxlength' => 255
  );
  $form['uniquename']= array(
    '#type' => 'textfield',
    '#title' => t('Unique Feature Name'),
    '#required' => TRUE,
    '#default_value' => $uniquename,
    '#description' => t('Enter a unique name for this feature.  This name must be unique for the organism and feature type.'),
    '#maxlength' => 255
  );
  // get the sequence ontology CV ID
  $values = array('name' => 'sequence');
  $cv = tripal_core_chado_select('cv', array('cv_id'), $values);
  $cv_id = $cv[0]->cv_id;

  $form['feature_type'] = array(
   '#title'       => t('Feature Type'),
   '#type'        => 'textfield',
   '#description' => t("Choose the feature type."),
   '#required'    => TRUE,
   '#default_value' => $feature_type,
   '#autocomplete_path' => "admin/tripal/tripal_cv/cvterm/auto_name/$cv_id",
  );

  // get the list of organisms
  $sql = "SELECT * FROM {Organism} ORDER BY genus, species";
  $org_rset = chado_query($sql);
  $organisms = array();
  $organisms[''] = '';
  while ($organism = $org_rset->fetchObject()) {
    $organisms[$organism->organism_id] = "$organism->genus $organism->species ($organism->common_name)";
  }
  $form['organism_id'] = array(
    '#title'       => t('Organism'),
    '#type'        => t('select'),
    '#description' => t("Choose the organism with which this feature is associated"),
    '#required'    => TRUE,
    '#default_value' => $organism_id,
    '#options'     => $organisms,
  );

  // Get synonyms
  $syn_text = '';
  if ($synonyms) {
    if (is_array($synonyms)) {
      foreach ($synonyms as $synonym) {
        $syn_text .= "$synonym->name\n";
      }
    }
    else {
      $syn_text = $synonyms;
    }
  }
  $form['synonyms']= array(
    '#type' => 'textarea',
    '#title' => t('Synonyms'),
    '#required' => FALSE,
    '#default_value' => $syn_text,
    '#description' => t('Enter alternate names (synonmys) for this feature to help in searching and identification. You may enter as many alternate names as needed each on different lines.'),
  );

  $form['residues']= array(
    '#type' => 'textarea',
    '#title' => t('Residues'),
    '#required' => FALSE,
    '#default_value' => $residues,
    '#description' => t('Enter the nucelotide sequences for this feature'),
  );

  $checked = '';
  if ($is_obsolete == 't') {
    $checked = '1';
  }
  $form['is_obsolete']= array(
    '#type' => 'checkbox',
    '#title' => t('Is Obsolete'),
    '#required' => FALSE,
    '#default_value' => $checked,
    '#description' => t('Check this box if this sequence should be retired'),
  );
  return $form;
}

/**
 * Implementation of hook_validate
 * 
 * This validation is being used for three activities:
 *   CASE A: Update a node that exists in both drupal and chado
 *   CASE B: Synchronizing a node from chado to drupal
 *   CASE C: Inserting a new node that exists in niether drupal nor chado
 *
 * @param $node
 *  
 *
 * @ingroup tripal_feature
 */
function chado_feature_validate($node, $form, &$form_state) {
  // remove surrounding white-space on submitted values
  $node->uniquename   = trim($node->uniquename);
  $node->fname        = trim($node->fname);
  $node->feature_type = trim($node->feature_type); 
  $node->residues     = trim($node->residues);
  
  // if this is a delete then don't validate
  if($node->op == 'Delete') {
    return;
  }
  
  // we are syncing if we do not have a node ID but we do have a feature_id. We don't
  // need to validate during syncing so just skip it.
  if (is_null($node->nid) and property_exists($node, 'feature_id') and $node->feature_id != 0) {
    return;
  }

  // Validating for an update
  if (property_exists($node, 'nid')) {
    
    // make sure the feature type is a real sequence ontology term
    $type = tripal_cv_get_cvterm_by_name($node->feature_type, NULL, 'sequence');
    if (!$type) {
      form_set_error('feature_type', t("The feature type is not a valid name from the Sequence Ontology."));
    }
    
    // if this is an update, we want to make sure that a different feature for
    // the organism doesn't already have this uniquename. We don't want to give
    // two sequences the same uniquename
    if (property_exists($node, 'feature_id') and $node->feature_id != 0) {
      $sql = "
        SELECT *
        FROM {feature} F
          INNER JOIN {cvterm} CVT ON F.type_id = CVT.cvterm_id
        WHERE
          F.uniquename     = :uname AND
          F.organism_id    = :organism_id AND
          CVT.name         = :cvtname AND
          NOT f.feature_id = :feature_id
      ";
      $args = array(':uname' => $node->uniquename, ':organism_id' => $node->organism_id,
        ':cvtname' => $node->feature_type, ':feature_id' => $node->feature_id);
      $result = chado_query($sql, $args)->fetchObject();
      if ($result) {
        form_set_error('uniquename', t("Feature update cannot proceed. The feature name '$node->uniquename' is not unique for this organism. Please provide a unique name for this feature."));
      }
    }
  }
  // Validating for an insert
  else {
      
    // make sure the feature type is a real sequence ontology term
    $type = tripal_cv_get_cvterm_by_name($node->feature_type, NULL, 'sequence');
    if (!$type) {
      form_set_error('feature_type', t("The feature type is not a valid name from the Sequence Ontology."));
    }
    
    // if this is an insert then we just need to make sure this name doesn't
    // already exist for this organism if it does then we need to throw an error
    $sql = "
      SELECT *
      FROM {feature} F
        INNER JOIN {cvterm} CVT ON F.type_id = CVT.cvterm_id
      WHERE
        F.uniquename  = :name AND
        F.organism_id = :organism_id AND
        CVT.name      = :cvtname
    ";
    $args = array(':name' => $node->uniquename, ':organism_id' => $node->organism_id, ':cvtname' => $node->feature_type);
    $result = chado_query($sql, $args)->fetchObject();
    if ($result) {
      form_set_error('uniquename', t("Feature insert cannot proceed. The feature name '$node->uniquename' already exists for this organism. Please provide a unique name for this feature."));
    }
  }
}


/**
 * Implement hook_access().
 *
 * This hook allows node modules to limit access to the node types they define.
 *
 *  @param $node
 *  The node on which the operation is to be performed, or, if it does not yet exist, the
 *  type of node to be created
 *
 *  @param $op
 *  The operation to be performed
 *
 *  @param $account
 *  A user object representing the user for whom the operation is to be performed
 *
 *  @return
 *  If the permission for the specified operation is not set then return FALSE. If the
 *  permission is set then return NULL as this allows other modules to disable
 *  access.  The only exception is when the $op == 'create'.  We will always
 *  return TRUE if the permission is set.
 *
 * @ingroup tripal_feature
 */
function chado_feature_node_access($node, $op, $account) {
  if ($op == 'create') {
    if (!user_access('create chado_feature content', $account)) {
      return FALSE;
    }
    return TRUE;
  }

  if ($op == 'update') {
    if (!user_access('edit chado_feature content', $account)) {
      return FALSE;
    }
  }
  if ($op == 'delete') {
    if (!user_access('delete chado_feature content', $account)) {
      return FALSE;
    }
  }
  if ($op == 'view') {
    if (!user_access('access chado_feature content', $account)) {
      return FALSE;
    }
  }
  return NULL;
}
/**
 *  When a new chado_feature node is created we also need to add information
 *  to our chado_feature table.  This function is called on insert of a new node
 *  of type 'chado_feature' and inserts the necessary information.
 *
 * @ingroup tripal_feature
 */
function chado_feature_insert($node) {

  $node->uniquename   = trim($node->uniquename);
  $node->fname        = trim($node->fname);
  $node->feature_type = trim($node->feature_type);
  $node->residues     = trim($node->residues);

  // remove spaces, newlines from residues
  $residues = preg_replace("/[\n\r\s]/", "", $node->residues);
  $obsolete = 'FALSE';
  if ($node->is_obsolete) {
    $obsolete = 'TRUE';
  }

  $feature_id = '';

  // if there is an feature_id in the $node object then this must be a sync so
  // we can skip adding the feature as it is already there, although
  // we do need to proceed with the rest of the insert
  if (!property_exists($node, 'feature_id')) {
    $values = array(
      'organism_id' => $node->organism_id,
      'name' => $node->fname,
      'uniquename' => $node->uniquename,
      'residues' => $residues,
      'seqlen' => drupal_strlen($residues),
      'is_obsolete' => $obsolete,
      'type_id' => $type[0]->cvterm_id,
      'md5checksum' => md5($residues)
    );
    $feature = tripal_core_chado_insert('feature', $values);
    if (!$feature) {
      drupal_set_message(t('Unable to add feature.'), 'warning');
      watchdog('tripal_feature', 'Insert feature: Unable to create feature where values: %values',
      array('%values' => print_r($values, TRUE)), WATCHDOG_WARNING);
      return;
    }
    $feature_id = $feature->feature_id;

    // add the genbank accession and synonyms
    chado_feature_add_synonyms($node->synonyms, $node->feature_id);
  }
  else {
    $feature_id = $node->feature_id;
  }

  // Make sure the entry for this feature doesn't already exist in the
  // chado_feature table if it doesn't exist then we want to add it.
  $check_org_id = chado_get_id_for_node('feature', $node->nid);
  if (!$check_org_id) {
    $record = new stdClass();
    $record->nid = $node->nid;
    $record->vid = $node->vid;
    $record->feature_id = $feature_id;
    drupal_write_record('chado_feature', $record);
  }
}

/**
 *
 *
 * @ingroup tripal_feature
 */
function chado_feature_update($node) {

  $node->uniquename   = trim($node->uniquename);
  $node->fname        = trim($node->fname);
  $node->feature_type = trim($node->feature_type);
  $node->residues     = trim($node->residues);


  $residues = preg_replace("/[\n\r\s]/", "", $node->residues);
  $obsolete = 'FALSE';
  if ($node->is_obsolete) {
    $obsolete = 'TRUE';
  }

  // get the feature type id
  $values = array(
    'cv_id' => array(
      'name' => 'sequence'
    ),
    'name' => $node->feature_type
  );
  $type = tripal_core_chado_select('cvterm', array('cvterm_id'), $values);

  $feature_id = chado_get_id_for_node('feature', $node->nid) ;

  if (sizeof($type) > 0) {
    $match = array(
      'feature_id' => $feature_id,
    );
    $values = array(
      'organism_id' => $node->organism_id,
      'name' => $node->fname,
      'uniquename' => $node->uniquename,
      'residues' => $residues,
      'seqlen' => drupal_strlen($residues),
      'is_obsolete' => $obsolete,
      'type_id' => $type[0]->cvterm_id,
      'md5checksum' => md5($residues)
    );
    $options = array('return_record' => TRUE);
    $status = tripal_core_chado_update('feature', $match, $values, $options);

    // add the genbank synonyms
    chado_feature_add_synonyms($node->synonyms, $feature_id);
  }
  else {
    drupal_set_message(t('Unable to update feature.'), 'warning');
    watchdog('tripal_feature',
    'Update feature: Unable to update feature where values: %values',
    array('%values' => print_r($values, TRUE)),
    WATCHDOG_WARNING
    );
  }


}
/**
 *
 *
 * @ingroup tripal_feature
 */
function chado_feature_delete($node) {

  $feature_id  = chado_get_id_for_node('feature', $node->nid);

  // if we don't have a library id for this node then this isn't a node of
  // type chado_library or the entry in the chado_library table was lost.
  if (!$feature_id) {
    return;
  }

  // remove the drupal content
  $sql_del = "DELETE FROM {chado_feature} WHERE nid = :nid AND vid = :vid";
  db_query($sql_del, array(':nid' => $node->nid, ':vid' => $node->vid));
  $sql_del = "DELETE FROM {node} WHERE nid = :nid AND vid = :vid";
  db_query($sql_del, array(':nid' => $node->nid, ':vid' => $node->vid));
  $sql_del = "DELETE FROM {node_revision} WHERE nid = :nid AND vid = :vid";
  db_query($sql_del, array(':nid' => $node->nid, ':vid' => $node->vid));


  // Remove data from feature tables of chado database.  This will
  // cause a cascade delete and remove all data in referencing tables
  // for this feature
  chado_query("DELETE FROM {feature} WHERE feature_id = :feature_id", array(':feature_id' => $feature_id));

  drupal_set_message(t("The feature and all associated data were removed from") .
  "chado");

}

/**
 *
 *
 * @ingroup tripal_feature
 */
function chado_feature_add_synonyms($synonyms, $feature_id) {

  // separate synomys by carriage returns
  $synonyms = preg_replace("/[\n\r]+/", " ", $synonyms);
  // split the synonyms into an array based on a space as the delimieter
  $syn_array = array();
  $syn_array = explode(" ", $synonyms);


  // remove any old synonyms
  $feature_syn_dsql = "DELETE FROM {feature_synonym} WHERE feature_id = :feature_id";
  if (!chado_query($feature_syn_dsql, array(':feature_id' => $feature_id))) {
    watchdog('tripal_feature', "Could not remove synonyms from feature. ", array(), WATCHDOG_ERROR);
    return;
  }

  // return if we don't have any synonmys to add
  if (!$synonyms) {
    return;
  }
  // iterate through each synonym and add it to the database
  foreach ($syn_array as $syn) {
    // skip this item if it's empty
    if (!$syn) {
      break;
    }

    // check to see if we have this accession number already in the database
    // if so then don't add it again. it messes up drupal if the insert fails.
    // It is possible for the accession number to be present and not the feature
    $synonym_sql = "SELECT synonym_id FROM {synonym} WHERE name = :name";
    $synonym = chado_query($synonym_sql, array(':name' => $syn))->fetchObject();
    if (!$synonym) {
      $synonym_isql = "
        INSERT INTO {synonym} (name, synonym_sgml, type_id)
        VALUES (:name, :synonym_sgml,
          (SELECT cvterm_id
           FROM {cvterm} CVT
             INNER JOIN {cv} ON CVT.cv_id = CV.cv_id
           WHERE CV.name = 'feature_property' and CVT.name = 'synonym')
          )
      ";
      if (!chado_query($synonym_isql, array(':name' => $syn, ':synonym_sgml' => $syn))) {
        watchdog('tripal_feature', "Could not add synonym. ", array(), WATCHDOG_WARNING);
        return;
      }
      // now get the synonym we just added
      $synonym_sql = "SELECT synonym_id FROM {synonym} WHERE name = :name";
      $synonym = chado_query($synonym_sql, array(':name' => $syn))->fetchObject();
    }

    // now add in our new sysnonym
    $feature_syn_isql = "
      INSERT INTO {feature_synonym} (synonym_id,feature_id,pub_id)
      VALUES (:synonym_id, :feature_id, :pub_id)";
    $args = array(':synonym_id' => $synonym->synonym_id, ':feature_id' => $feature_id, ':pub_id'=> 1);
    if (!chado_query($feature_syn_isql, $args)) {
      watchdog('tripal_feature', "Could not associate synonym with feature. ", array(), WATCHDOG_WARNING);
      return;
    }
  }
}

/**
 *  When a node is requested by the user this function is called to allow us
 *  to add auxiliary data to the node object.
 *
 * @ingroup tripal_feature
 */
function chado_feature_load($nodes) {

  foreach ($nodes as $nid => $node) {
    // find the feature and add in the details
    $feature_id = chado_get_id_for_node('feature', $nid);

    // build the feature variable
    $values = array('feature_id' => $feature_id);
    $feature = tripal_core_generate_chado_var('feature', $values);
    $nodes[$nid]->feature = $feature;

    // by default, the titles are saved using the unique constraint.  We will
    // keep it the same, but remove the duplicate name if the unique name and name
    // are identical. This doesn't change the title saved in the database, just what is shown
    // to the user on the page
    $title_type = variable_get('chado_feature_title', 'unique_constraint');
    if ($title_type == 'unique_constraint') {
      if (strcmp($feature->name, $feature->uniquename)==0) {
        $node->title = $feature->name . " (" . $feature->type_id->name . ") " . $feature->organism_id->genus . " " . $feature->organism_id->species ;
      }
      // in previous version of Tripal, the feature title was simply the unique name.
      // so, we recreate the title just to be sure all of our feature pages are consistent
      else {
        $node->title = $feature->name . ", " . $feature->uniquename . " (" . $feature->type_id->name . ") " . $feature->organism_id->genus . " " . $feature->organism_id->species ;
      }
    }
    // set the title to be the feature name or uniquename as configured
    if ($title_type == 'feature_name') {
      $node->title = $feature->name;
    }
    if ($title_type == 'feature_unique_name') {
      $node->title = $feature->uniquename;
    }
  }
}
/**
 *  Provide information to drupal about the node types that we're creating
 *  in this module
 *
 * @ingroup tripal_feature
 */
function tripal_feature_node_info() {
  $nodes = array();

  $nodes['chado_feature'] = array(
    'name'        => t('Feature'),
    'base'        => 'chado_feature',
    'description' => t('A feature from the chado database'),
    'has_title'   => FALSE,
    'title_label' => t('Feature'),
    'has_body'    => FALSE,
    'body_label'  => t('Feature Description'),
    'locked'      => TRUE
  );
  return $nodes;
}
/**
 *
 * @ingroup tripal_feature
 */
function tripal_feature_node_presave($node) {

  // set the title to ensure it is always unique
  switch ($node->type) {
  	case 'chado_feature':
  	  $values = array('organism_id' => $node->organism_id);
  	  $organism = tripal_core_chado_select('organism', array('genus', 'species'), $values);
  	  $node->title = $node->fname . ', ' . $node->uniquename . ' (' . $node->feature_type . ') ' . $organism[0]->genus . ' ' . $organism[0]->species;
  	  break;
  }
}

/**
 *
 * @ingroup tripal_feature
 */
function tripal_feature_node_insert($node) {

  // set the URL path after inserting.  We do it here because we do not
  // know the feature_id in the presave
  switch ($node->type) {
  	case 'chado_feature':
  	  if (!$node->feature_id) {
  	    $sql = "SELECT * FROM {chado_feature} WHERE nid = :nid";
  	    $chado_feature = db_query($sql, array(':nid' => $node->nid))->fetchObject();
  	    $node->feature_id = $chado_feature->feature_id;
  	  }

  	  // remove any previous alias
  	  db_query("DELETE FROM {url_alias} WHERE source = :source", array(':source' => "node/$node->nid"));

  	  // set the URL for this feature page
  	  $url_alias = tripal_feature_get_feature_url($node);
  	  $path_alias = array("source" => "node/$node->nid", "alias" => $url_alias);
  	  path_save($path_alias);
  	  break;
  }
}

/**
 *
 * @ingroup tripal_feature
 */
function tripal_feature_node_view($node, $view_mode, $langcode) {
  switch ($node->type) {
  	case 'chado_feature':
  	  // Show feature browser and counts
  	  if ($view_mode == 'full') {
  	    $node->content['tripal_feature_alignments'] = array(
  	      '#value' => theme('tripal_feature_alignments', array('node' => $node)),
  	    );
  	    $node->content['tripal_feature_analyses'] = array(
  	      '#value' => theme('tripal_feature_analyses', array('node' => $node)),
  	    );
  	    $node->content['tripal_feature_base'] = array(
  	      '#value' => theme('tripal_feature_base', array('node' => $node)),
  	    );
  	    $node->content['tripal_feature_featurepos'] = array(
  	      '#value' => theme('tripal_feature_featurepos', array('node' => $node)),
  	    );
  	    $node->content['tripal_feature_properties'] = array(
  	      '#value' => theme('tripal_feature_properties', array('node' => $node)),
  	    );
  	    $node->content['tripal_feature_publications'] = array(
  	      '#value' => theme('tripal_feature_publications', array('node' => $node)),
  	    );
  	    $node->content['tripal_feature_references'] = array(
  	      '#value' => theme('tripal_feature_references', array('node' => $node)),
  	    );
  	    $node->content['tripal_feature_relationships'] = array(
  	      '#value' => theme('tripal_feature_relationships', array('node' => $node)),
  	    );
  	    $node->content['tripal_feature_seqence'] = array(
  	      '#value' => theme('tripal_feature_sequence', array('node' => $node)),
  	    );
  	    $node->content['tripal_feature_synonyms'] = array(
  	      '#value' => theme('tripal_feature_synonyms', array('node' => $node)),
  	    );
  	    $node->content['tripal_feature_terms'] = array(
  	      '#value' => theme('tripal_feature_terms', array('node' => $node)),
  	    );
  	  }
  	  if ($view_mode == 'teaser') {
  	    $node->content['tripal_feature_teaser'] = array(
  	      '#value' => theme('tripal_feature_teaser', array('node' => $node)),
  	    );
  	  }
  	  break;
  	case 'chado_organism':
  	  // Show feature browser and counts
  	  if ($view_mode == 'full') {
  	    $node->content['tripal_organism_feature_counts'] = array(
  	      '#value' => theme('tripal_organism_feature_counts', array('node' => $node)),
  	    );
  	    $node->content['tripal_organism_feature_browser'] = array(
  	      '#value' => theme('tripal_organism_feature_browser', array('node' => $node)),
  	    );
  	  }
  	  break;
  	  // TODO: handle these node types. Should we also have a feature browser?
  	case 'chado_library':
  	  break;
  	case 'chado_stock':
  	  break;
  	case 'chado_analysis':
  	  break;
  }
}
/**
 *
 * @ingroup tripal_feature
 */
function tripal_feature_node_update($node) {

  // add items to other nodes, build index and search results
  switch ($node->type) {
  	case 'chado_feature':
  	  // remove any previous alias
  	  db_query("DELETE FROM {url_alias} WHERE source = :source", array(':source' => "node/$node->nid"));

  	  // set the URL for this feature page
  	  $url_alias = tripal_feature_get_feature_url($node);
  	  $path_alias = array("source" => "node/$node->nid", "alias" => $url_alias);
  	  path_save($path_alias);
  	  break;
  }
}