Drupal 7: Set Default Image to Content with Update Hook

Here is the update hook to add default image to article content:

/**
 * Update default image on field base.
 */
function mymodule_update_7300() {
  $field_name = 'field_fb_article_image';
  $filename = 'images.png';
  $source = drupal_get_path('module', 'mymodule') . '/includes/images' . '/' . $filename;
  // Load field info.
  $field = field_info_field($field_name);
  // Create new file object and get new fid.
  if (file_exists($source)) {
    $file = new stdClass;
    $file->filename = $filename;
    $file->timestamp = REQUEST_TIME;
    $file->uri = $source;
    $file->filemime = file_get_mimetype($source);
    $file->uid = 1;
    $file->status = 1;
    $file = file_copy($file, 'public://files', FILE_EXISTS_REPLACE);
    $fid = $file->fid;
    // Replace old fid with new fid.
    $field['settings']['default_image'] = (string) $fid;
    // Update field.
    field_update_field($field);
  }
}
 

Drupal 7: How to create update hook

Step 1: Go to the following path and create update hook to perform the action.

sites/all/modules/custom/mymodule/mymodule.install

/**
 * Disabled PSL Newsletter module
 * Implements hook_update_N()
 */
function mymodule_update_7300(&$sandbox) {
   module_disable(array('newsletter'));
   return 'Newsletter has been disabled';
}
 

Step 2: Go to project root path and run drush updb -y

Drupal 7: Calling Session Variable with Javascript

Step 1: Prepare hook menu to call getSession function. Return the $result variable after this line $result = $_SESSION['_custom_variables'];

sites/all/modules/custom/mymodule/mymodule.module

/** Comment **/ 
/**
 * Implements hook_menu().
 */
function mymodule_menu() {
  // track url
  $items['getSession'] = array(
    'page callback'    => 'mymodule_getSession_ajax',
    'access callback' => TRUE
  );
  return $items;
}
/**
 * Called by ajax request to getSession
 */
function mymodule_getSession_ajax() {
  if(isset($_POST['action'])) {
    $action = $_POST['action'];
    unset($_POST['action']);
  }
  else {
    $action = 'default';
  }
  mymodule_getSession('ajax', $action, $_POST);
}
/**
 *
 * @param string $type ajax|server This informs the function if it should use the current request or REFERER as the url
 * @param string $action action to send
 * @param array $vars Associative array of variables to send as custom vars
 */
function mymodule_getSession($type, $action, $vars=array()){
  $url = $_SERVER['HTTP_REFERER'];
  $params = parse_url($url);
  $result = array();
  $customVariable = ['MemberID', 'EmailID', 'SpecialtyID'];
  if(isset($params['query'])){
    parse_str($params['query'], $query);
    foreach ($query as $key => $value) {
      if(in_array($key, $customVariable))
      {
        $_SESSION['_custom_variables'][$key] = $value;
      }
    }
  }
  $result = $_SESSION['_custom_variables'];
  print drupal_json_output($result);
  exit();
}

Step 2: Call hook menu with ajax, return the result after success call.

sites/all/themes/mytheme/js/mytheme.js

/** Comment **/ 
(function ($) {
jQuery(document).ready(function() {
  var mysession = getSession(); 
  console.log(mysession);
/*
   * Get Session Function
   * @action is the name of the page
   * @actionType is either 'page_view' or 'link'
   */
  function getSession() {
    // add action and action type
    var data = {action:'custom_variables'};
    var basePath = '';
    var result;
    if ( (Drupal.settings.basePath != undefined) && (Drupal.settings.basePath != '/') ) {
      basePath = Drupal.settings.basePath;
    }
    basePath = basePath + '/getSession';
    basePath = basePath.replace('//', '/');
    jQuery.ajax({
      url: basePath,
      type:'POST',
      dataType:'json',
      data:data,
      async:(jQuery.browser.safari || jQuery.browser.mozilla) ? false : true,
      success: function(data) {
        // for this current implementation, there is no need for action upon success
        result = data;
        },
      error: function(xhr, status, error) {
        // error
      }
    });
    return result;
  }
})
}
)(jQuery);