dkan_datastore.module

<?php
/**
 * @file
 * Creates DKAN Datastore.
 */

// Datastore is created for a given resource.
define('DKAN_DATASTORE_EMPTY', 0);
// Datastore is created for a given resource.
define('DKAN_DATASTORE_EXISTS', 1);
// File is attached to a resource, but not added to the datastore.
define('DKAN_DATASTORE_FILE_EXISTS', 2);
// File is attached to a resource, but cannot be added to the datastore.
define('DKAN_DATASTORE_WRONG_TYPE', 3);

include_once "dkan_datastore.features.inc";

/**
 * Implements hook_menu().
 */
function dkan_datastore_menu() {
  $items['node/%dkan_datastore_resource/download'] = array(
    'title callback' => 'dkan_datastore_download_title',
    'title arguments' => array(1),
    'page callback' => 'dkan_datastore_download',
    'page arguments' => array(1),
    'access callback' => 'dkan_datastore_download_access',
    'access arguments' => array('view', 1),
    'file' => 'dkan_datastore.pages.inc',
    'weight' => '20',
    'type' => MENU_LOCAL_TASK,
  );
  
  $items['node/%dkan_datastore_resource/data'] = array(
    'page callback' => 'dkan_datastore_proxy',
    'page arguments' => array(1),
    'access callback' => 'dkan_datastore_download_access',
    'access arguments' => array('view', 1),
    'file' => 'dkan_datastore.pages.inc',
    'type' => MENU_CALLBACK,
  );

  $items['node/%node/api'] = array(
    'title' => 'Data API',
    'page callback' => 'dkan_datastore_datastore_api',
    'page arguments' => array(1),
    'access callback' => 'dkan_datastore_datastore_api_access',
    'access arguments' => array(1),
    'file' => 'dkan_datastore.pages.inc',
    'weight' => '25',
    'type' => MENU_LOCAL_TASK,
  );
  $items['node/%node/datastore'] = array(
    'title' => 'Manage Datastore',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('dkan_datastore_import_tab_form', 1),
    'access callback' => 'dkan_datastore_feeds_access',
    'access arguments' => array('import', 1),
    'file' => 'dkan_datastore.pages.inc',
    'weight' => '15',
    'type' => MENU_LOCAL_TASK,
  );
  $items['node/%node/datastore/import'] = array(
    'title' => 'Import',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('dkan_datastore_import_tab_form', 1),
    'access callback' => 'dkan_datastore_feeds_access',
    'access arguments' => array('import', 1),
    'file' => 'dkan_datastore.pages.inc',
    'weight' => 10,
    'type' => MENU_DEFAULT_LOCAL_TASK,
  );
  $items['node/%node/datastore/delete-items'] = array(
    'title' => 'Delete items',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('dkan_datastore_delete_tab_form', NULL, 1),
    'access callback' => 'dkan_datastore_feeds_access',
    'access arguments' => array('clear', 1),
    'file' => 'dkan_datastore.pages.inc',
    'weight' => 11,
    'type' => MENU_LOCAL_TASK,
  );
  $items['node/%node/datastore/unlock'] = array(
    'title' => 'Unlock',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('dkan_datastore_unlock_tab_form', NULL, 1),
    'access callback' => 'dkan_datastore_feeds_access',
    'access arguments' => array('unlock', 1),
    'file' => 'dkan_datastore.pages.inc',
    'weight' => 11,
    'type' => MENU_LOCAL_TASK,
  );
  $items['node/%node/datastore/drop'] = array(
    'title' => 'Drop Datastore',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('dkan_datastore_drop_tab_form', 1),
    'access callback' => 'dkan_datastore_feeds_access',
    'access arguments' => array('drop', 1),
    'file' => 'dkan_datastore.pages.inc',
    'weight' => 12,
    'type' => MENU_LOCAL_TASK,
  );
  return $items;
}

/**
 * Retrieves the url to the physical resource and 
 * the type of it.
 */
function dkan_datastore_resource_link_type($node) {
  $node_wrapper = entity_metadata_wrapper('node', $node);
  $file_field = dkan_datastore_file_upload_field();
  $remote_file_field = dkan_datastore_file_link_field();
  $api_field = dkan_datastore_api_link_field();
  $type = dkan_datastore_node_type();

  if($node->type == $type && $file = $node_wrapper->{$file_field}->value()) {
    $uri = isset($file->uri) ? $file->uri : $file['uri'];
    $url = file_create_url($uri);
    return array('url' => $url, 'type' => 'upload');
  } else if($remote_file = $node_wrapper->{$remote_file_field}->value()) {
    return array('url' => $remote_file['uri'], 'type' => 'remote');
  } else if($link = $node_wrapper->{$api_field}->value()){
    return array('url' => $link['url'], 'type' => 'link');
  } else {
    drupal_set_message(t('No download available for this resource'));
    return array('type' => 'upload');
  }  
}

/**
 * Title callback to change the download link text
 * based on the type of the resource link.
 */
function dkan_datastore_download_title($node) {
  $resource_link_type = dkan_datastore_resource_link_type($node);
  return ($resource_link_type['type'] == 'link') ? t('Go to resource') : t('Download');
}

/**
 * Implements hook_menu_alter().
 */
function dkan_datastore_menu_alter(&$items) {
  // Removing these here, readding in hook_menu().
  unset($items['node/%node/delete-items']);
  unset($items['node/%node/import']);
  unset($items['node/%node/unlock']);
}

/**
 * Copy of feeds_access.
 */
function dkan_datastore_feeds_access($action, $node) {
  if (!in_array($action, array('import', 'clear', 'unlock', 'drop'))) {
    // If $action is not one of the supported actions, we return access denied.
    return FALSE;
  }
  if ($action == 'drop' && user_access('manage datastore')) {
    return TRUE;
  }
  if ($action != 'import') {
    if ($importer_ids = feeds_get_importer_ids($node->type, $node->nid)) {
      foreach ($importer_ids as $importer_id) {
        $source_config = feeds_source($importer_id, $node->nid);
        $fetcher = get_class($source_config->importer->fetcher);
        $source = isset($source_config->config[$fetcher]['source']) ? $source_config->config[$fetcher]['source'] : '';
        if ($source) {
          return TRUE;
        }
      }
      return FALSE;
    }
    else {
      return FALSE;
    }
  }

  if (is_string($node)) {
    $importer_id = $node;
  }
  elseif ($node->type) {
    $importer_id = feeds_get_importer_id($node->type);
  }

  // Check for permissions if feed id is present, otherwise return FALSE.
  if ($importer_id) {
    if (user_access('administer feeds') || user_access("{$action} {$importer_id} feeds")) {
      return TRUE;
    }
  }
  return FALSE;
}

/**
 * Access callback for Download.
 */
function dkan_datastore_download_access($action, $resource) {
  $type = dkan_datastore_node_type();
  $node = is_object($resource) ? $resource : node_load($resource);

  if ($node->type != $type) {
    return FALSE;
  }

  return node_access('view', $node);
}

/**
 * Access callback for Data API instructions.
 */
function dkan_datastore_datastore_api_access($resource) {
  $status = dkan_datastore_status($resource);
  if ($status == DKAN_DATASTORE_FILE_EXISTS && !user_access('manage datastore')) {
    return FALSE;
  }
  if ($status != DKAN_DATASTORE_WRONG_TYPE) {
    $file_field = dkan_datastore_file_upload_field();
    $link_field = dkan_datastore_file_link_field();
    $type = dkan_datastore_node_type();
    $node = is_object($resource) ? $resource : node_load($resource);
    $upload = '';
    $link = '';
    if (isset($node->$file_field) && $node->$file_field) {
      $upload = isset($node->{$file_field}[$node->language]) ? $node->{$file_field}[$node->language] : $node->{$file_field}['und'];
    }
    if (isset($node->{$link_field}) && $node->{$link_field}) {
      $link = isset($node->{$link_field}[$node->language]) ? $node->{$link_field}[$node->language] : $node->{$link_field}['und'];
    }
    if ($node->type == $type && ($upload || $link)) {
      return node_access('view', $node);
    }
    else {
      return FALSE;
    }
  }
  return FALSE;
}

/**
 * Load node by id or uuid.
 */
function dkan_datastore_resource_load($id) {
  try {
    // Id is a nid.
    if (is_numeric($id)) {
      return node_load($id);
    }
    // Id is a uuid and uuid is installed.
    else if (function_exists('entity_uuid_load')) {
      $node = entity_uuid_load('node', array($id));
      return ($node) ? reset($node) : FALSE;
    }

  }
  catch (Exception $e) {
    return FALSE;
  }

  return FALSE;
}

/**
 * Access callback for back link.
 */
function dkan_datastore_back_access($node) {
  if ($node->type != 'resource') {
    return FALSE;
  }
  else {
    return node_access('view', $node);
  }
}

/**
 * Access callback for 'Add Resource' tab.
 */
function dkan_add_resource($node) {
  if ($node->type != 'dataset') {
    return FALSE;
  }
  else {
    return _node_add_access();
  }
}

/**
 * Implements hook_node_update().
 */
function dkan_datastore_node_insert($node) {
  $type = dkan_datastore_node_type();
  if ($node->type == $type) {
    if (!isset($node->feeds)) {
      // Feeds only saves if there is a form present. We want this to work
      // programmatically as well.
      feeds_node_prepare($node);
      feeds_node_update($node);
    }
  }
}

/**
 * Implements hook_node_update().
 */
function dkan_datastore_node_update($node) {
  $type = dkan_datastore_node_type();
  if ($node->type == $type) {
    $file_field = dkan_datastore_file_upload_field();
    $link_field = dkan_datastore_file_link_field();
    // See if we have a file link or upload.
    $wrapper = entity_metadata_wrapper('node', $node);
    $file = $wrapper->{$file_field}->value();
    if (!$file) {
      $link = $wrapper->{$link_field}->value();
      if (isset($link) && isset($link['fid'])) {
        $file = file_load($link['fid']);
      }
      elseif (isset($link) && isset($link->fid)) {
        $file = $link;
      }
      else {
        $file = '';
      }
    }
    if ($file) {
      if (!isset($node->feeds)) {
        // Feeds only saves if there is a form present. We want this to work
        // programmatically as well.
        feeds_node_prepare($node);
      }
      // Remove node from feeds list if not csv.
      elseif ($file->filemime != 'text/csv') {
        feeds_node_delete($node);
      }
    }
  }
}

/**
 * Implements hook_permission().
 */
function dkan_datastore_permission() {
  return array(
    'manage datastore' => array(
      'title' => t('Manage Datastore'),
    ),
    'manage datastore settings' => array(
      'title' => t('Manage Datastore Settings')
    )
  );
}

/**
 * Implements hook_node_view().
 */
function dkan_datastore_node_view($node, $view_mode, $langcode) {

  $type = dkan_datastore_node_type();
  if ($node->type == $type) {
    $status = dkan_datastore_status($node);
    if (user_access('manage datastore') && $status && $view_mode == 'full') {
      if ($status == DKAN_DATASTORE_FILE_EXISTS) {
        drupal_set_message(t('Your file for this resource is not added to the datastore. Click "Manage Datastore" to import file into the datastore.'));
      }
      elseif ($status == DKAN_DATASTORE_EXISTS) {
        drupal_set_message(t('Your file for this resource has been added to the datastore.'));
      }
    }
  }
}

/**
 * Determines status of datastore attached to resource node.
 */
function dkan_datastore_status($node) {
  if($file = dkan_datastore_file_field($node)) {
    if(dkan_datastore_is_importable($file)){
      $node = entity_metadata_wrapper('node', $node);
      if($status = $node->field_datastore_status->value()) {
        return $status;
      } else {
        return DKAN_DATASTORE_FILE_EXISTS;
      }
    } else {
      return DKAN_DATASTORE_WRONG_TYPE;
    }
  } else {
    return DKAN_DATASTORE_EMPTY;
  }
}

/**
 * Determines if a resource can be imported
 */
function dkan_datastore_is_importable($file) {
  return (is_object($file) && $file->filemime == 'text/csv') || (is_array($file) && array_key_exists('filemime', $file) && $file['filemime'] == 'text/csv');
}

/**
 * Determines if records exist in a datastore.
 *
 * @param string $nid
 *   Node id for resource node.
 */
function dkan_datastore_records($nid) {
  if (function_exists('dkan_datastore_api_get_feeds_source')) {
    $source_id = dkan_datastore_api_get_feeds_source($nid);
    if ($table = feeds_flatstore_processor_table_name($source_id, $nid)) {
      if (db_table_exists($table)) {
        $query = db_select($table, 't')
          ->fields('t', array('timestamp'))
          ->range(0, 1);
        if ($result = $query->execute()) {
          return TRUE;
        }
      }
    }
  }
  return FALSE;
}

/**
 * Retrieves loaded file from resource node.
 */
function dkan_datastore_file_field($node) {
  $type = dkan_datastore_node_type();
  if (isset($node->type) && $node->type == $type) {
    $file_field = dkan_datastore_file_upload_field();
    $link_field = dkan_datastore_file_link_field();
    $wrapper = entity_metadata_wrapper('node', $node);
    $file = isset($wrapper->{$file_field}) ? $wrapper->{$file_field}->value() : '';
    $link = isset($wrapper->{$link_field}) ? $wrapper->{$link_field}->value() : '';
    if (isset($file)) {
      return $file;
    }
    elseif ($link) {
      return $link;
    }
  }
  return FALSE;
}

/**
 * Implements hook_field_formatter_info().
 */
function dkan_datastore_field_formatter_info() {
  $formatters = array(
    'dkan_datastore_status_formatter' => array(
      'label' => t('Datastore Status'),
      'field types' => array('recline_field'),
    ),
  );
  return $formatters;
}

/**
 * Implements hook_field_formatter_view().
 */
function dkan_datastore_field_formatter_view($entity_type, $entity, $field, $instance, $langcode, $items, $display) {

  $element = array();

  foreach ($items as $delta => $item) {
    $item['entity'] = $entity;
    $element[$delta] = array(
      '#theme' => 'dkan_datastore_status_formatter',
      '#item' => $item,
    );
  }

  return $element;
}

/**
 * Implements hook_theme().
 */
function dkan_datastore_theme() {
  return array(
    'dkan_datastore_status_formatter' => array(
      'variables' => array('item' => NULL),
    ),
  );
}

/**
 * Returns HTML for an recline field formatter.
 *
 * @param array $variables
 *   An associative array containing:
 *   - item: Associative array of recline field.
 *
 * @ingroup themeable
 */
function theme_dkan_datastore_status_formatter(array $variables) {
  $status = dkan_datastore_status($variables['item']['entity']);
  if ($status === DKAN_DATASTORE_FILE_EXISTS) {
    return '<span class="circle false" title="' . t('A file has been uploaded but not added to the datastore') . '">' . t('Data ready to be added') . '</span>';
  }
  elseif ($status === DKAN_DATASTORE_EXISTS) {
    return '<span class="circle true">' . t('Datastore enabled') . '</span>';
  }
  return '<span class="circle na">' . t('Correct file type not attached to resource') . '</span>';
}

/**
 * Gets a datastore instance.
 *
 * @param string $id
 *   The unique id of the importer object.
 *
 * @return Datastore
 *   A Datastore object or an object of a class defined by the Drupal
 *   variable 'dkan_datastore_class'. There is only one importer object
 *   per $id system-wide.
 */
function dkan_datastore_go($id = NULL, $class = NULL) {
  if (!$class) {
    $class = variable_get('dkan_datastore_class', 'DkanDatastore');
  }
  return Datastore::instance($class, $id);
}

/**
 * Returns name of upload field.
 */
function dkan_datastore_file_upload_field() {
  static $field;
  if (!$field) {
    $field = 'field_upload';
    drupal_alter('dkan_datastore_file_upload_field', $field);
  }
  return $field;
}

/**
 * Returns name of link api field.
 */
function dkan_datastore_api_link_field() {
  static $field;
  if (!$field) {
    $field = 'field_link_api';
    drupal_alter('dkan_datastore_field_link_api', $field);
  }
  return $field;
}

/**
 * Returns name of remote file field.
 */
function dkan_datastore_file_link_field() {
  static $field;
  if (!$field) {
    $field = 'field_link_remote_file';
    drupal_alter('dkan_datastore_field_link_remote_file', $field);
  }
  return $field;
}

/**
 * Returns name of node type that the Datastore is attached to.
 */
function dkan_datastore_node_type() {
  static $node_type;
  if (!$node_type) {
    $node_type = 'resource';
    drupal_alter('dkan_datastore_node_type', $node_type);
  }
  return $node_type;
}

/**
 * Implements hook_feeds_after_import().
 */
function dkan_datastore_feeds_after_import(FeedsSource $source) {
  $importer_id = $source->importer->id;
  $importers = array('dkan_file', 'dkan_link');
  if(empty($source->exception) && in_array($importer_id, $importers)) {
    $node = node_load($source->feed_nid);
    $node = entity_metadata_wrapper('node', $node);
    $node->field_datastore_status->set(DKAN_DATASTORE_EXISTS);
    $node->save();
  }
}

/**
 * Implements hook_node_presave().
 */
function dkan_datastore_node_presave($node) {
  if(is_object($node) && $node->type == 'resource') {
    $wrap = entity_metadata_wrapper('node', $node);
    $wrap->field_datastore_status->set(dkan_datastore_status($node));
  }
}

/**
 * Implements hook_cron_queue_info().
 */
function dkan_datastore_cron_queue_info() {
  $queues['dkan_datastore_queue'] = array(
     'worker callback' => 'dkan_datastore_queue_import_worker',
     'time' => 120,
     'skip on cron' => FALSE,
  );

  return $queues;
}

/**
 * Utility function for add a new resource to datastore queue.
 */
function dkan_datastore_queue_import($uuid, $fid) {
  $item = array(
    'uuid' => $uuid,
    'fid' => $fid
  );
  DrupalQueue::get('dkan_datastore_queue')->createItem($item);
  watchdog('dkan_datastore', t('Added %file to queue for import into datastore', array('%file' => $fid)));
}

/**
 * Callback used with queue for index content into datastore.
 */
function dkan_datastore_queue_import_worker($item) {
  $file = file_load($item['fid']);
  $uri = $file->uri;
  $file_path = file_create_url($uri);
  $datastore = dkan_datastore_go($item['uuid']);
  $datastore->updateByFile($file_path);
}