gistfile1.php

<?php
/**
 * @file
 * Apache Solr external index module - example module for using external data.
 */

/**
 * implements hook_apachesolr_query_alter().
 */
function apachesolr_external_index_apachesolr_query_alter(DrupalSolrQueryInterface $query) {
  
  // Check if this is an 'external' environment...
  $is_external = apachesolr_environment_variable_get(
    $query->solr('getId'), 'is_external', FALSE);
  
  // and alter the query accordingly
  if($is_external) {
    
    // Get external fields.
    $query->replaceParam('fl',
       array('id', 'obj_desc', 'obj_type',
             'provider', 'species', 'src_url',
             'timestamp', 'score', 'shard:[shard]'
       )
    );
    
    // Specify the field to use for highlighting
    $query->replaceParam('hl.fl', 'obj_desc');
  }
}
/**
 * implements hook_apachesolr_search_result_alter().
 */
function apachesolr_external_index_apachesolr_search_result_alter($doc, $extra, $query) {
  
  // Check if this is an 'external' environment...
  $is_external = apachesolr_environment_variable_get(
    $query->solr('getId'), 'is_external', FALSE);
  
  // and alter the results accordingly
  if($is_external) {
    
    // Hacking our results into a format expected by apachesolr
    $doc->content     = $doc->obj_desc;
    $doc->teaser      = $doc->obj_desc;
    
    $doc->ds_created  = $doc->timestamp;
    $doc->ds_changed  = $doc->timestamp;
    $doc->tos_name    = 'tos';
    
    $doc->label       = $doc->id; // Pretty label
    $doc->path        = $doc->src_url; // URL put on label
    
    // apachesolr_search module expects entity_type to be set.
    $doc->entity_type = $doc->obj_type[0];
  }
}
/**
 * Adds the 'external' option in the settings of any environment, if
 * set, tweaks the environment a bit...
 */
function apachesolr_external_index_form_apachesolr_environment_edit_form_alter(&$form, &$form_state, $form_id) {

  // If the environment already exists, we can lookup the existing
  // value of 'is_external', else use FALSE
  $is_external = FALSE;
  if (count($form_state['build_info']['args'])) {
    $environment = reset($form_state['build_info']['args']);
    $is_external = apachesolr_environment_variable_get(
      $environment['env_id'], 'is_external', FALSE);
  }

  $form['make_external'] = array(
    '#type' => 'checkbox',
    '#title' => t('Make this environment \'external\''),
    '#default_value' => $is_external,
    '#description' => t('Note, the external index will always be read-only.'),
  );

  // and store it appropriately in the form...
  $form['actions']['save']['#submit'][] =
    'apachesolr_external_index_environment_edit_submit';
  $form['actions']['save_edit']['#submit'][] =
    'apachesolr_external_index_environment_edit_submit';
}
/**
 * Submit callback for saving an environment to make it 'external'
 */
function apachesolr_external_index_environment_edit_submit($form, &$form_state) {
  $env_id = $form_state['values']['env_id'];

  if ($form_state['values']['make_external']) {
    apachesolr_environment_variable_set($env_id, 'is_external', TRUE);

    // We also tweak the environment configuration here too...
    apachesolr_environment_variable_set($env_id, 'apachesolr_read_only', 1);
    
    // If we have facetapi installed, define our custom facets...
    if(module_exists('facetapi')){
      apachesolr_environment_variable_set($env_id, 'facet callbacks',
        // See callback below
        array('apachesolr_external_index_facet_callback'));
    }
  }
  else {
    apachesolr_environment_variable_del(
      $env_id, 'is_external');
  }
}
/**
 * Implements an environment-specific facet callback called from
 * apachesolr_facetapi_facet_info()
 *
 * Returns the same values as used by hook_facetapi_facet_info(). We
 * could use that hook, but then our facets would be added to rather
 * than replace the defaults defined by the apachesolr module.
 *
 * @param array $searcher_info
 *   The definition of the searcher that facets are being collected for.
 *
 * @return array
 *   An associative array keyed by unique name of the facet.
 */
function apachesolr_external_index_facet_callback($searcher_info) {
  $facets = array();

  $facets['obj_type'] = array(
    'label' => t('Data type'),
    'description' => t('Filter by data type.'),
    'field' => 'obj_type',
    'facet mincount allowed' => TRUE,
  );
  
  $facets['species'] = array(
    'label' => t('Species'),
    'description' => t('Filter by species.'),
    'field' => 'species',
    'facet mincount allowed' => TRUE,
  );

  $facets['provider'] = array(
    'label' => t('Database'),
    'description' => t('Filter by database.'),
    'field' => 'provider',
    'facet mincount allowed' => TRUE,
  );
  
  return $facets;
}