Example on how to migrate webform/submissions

this would be great!

Well, I recently had my first shot at migrating webform submissions (note there is no migration path currently implemented for webforms themselves, I manually rebuilt them). Here's a class derived from migrate_d2d's DrupalMigration (this was a D6-to-D7 deal), scrubbed of some customer-specific stuff, with extra comments for the general audience. It's key to note that this is the migration for the submissions to a single webform.

class ExampleWebformMigration extends DrupalMigration {
  public function __construct($arguments) {
    parent::__construct($arguments);
    $this->dependencies[] = 'User';

    // These are the form_key values from webform_component - never got around to giving them nice labels
    $fields = array(
      'username' => 'username',
      'first_name' => 'first_name',
      'last_name' => 'last_name',
      'email_address' => 'email_address',
      'date_of_event' => 'date_of_event',
      'city__state' => 'city__state',
      'number_of_tickets_purchased' => 'number_of_tickets_purchased',
      'guests' => 'guests',
    );
    $this->source = new MigrateSourceSQL($this->query(), $fields, NULL,
      array('map_joinable' => FALSE));
    // Find the destination webform by title
    $nodes = node_load_multiple(array(), array('type' => 'webform',
      'title' => 'Example Sign Up'));
    $node = reset($nodes);
    $this->destination = new MigrateDestinationWebformSubmission($node);
    $this->map = new MigrateSQLMap($this->machineName,
       array(
         'sid' => array('type' => 'int',
                        'unsigned' => TRUE,
                        'not null' => TRUE,
                        'description' => 'Webform submission ID',
                        'alias' => 's',
                       ),
       ),
       MigrateDestinationWebformSubmission::getKeySchema()
    );

    $this->addSimpleMappings(array('submitted', 'remote_addr'));
    $this->addFieldMapping('uid', 'uid')
         ->sourceMigration('User');
    $this->addFieldMapping('is_draft')
         ->defaultValue(0);
    // On the destination side we get these unintuitive form keys
    $this->addFieldMapping('data_new_1346960272729', 'username');
    $this->addFieldMapping('data_new_1346960598775', 'first_name');
    $this->addFieldMapping('data_new_1346960634561', 'last_name');
    $this->addFieldMapping('data_new_1346960673212', 'email_address');
    $this->addFieldMapping('data_new_1346960718925', 'date_of_event');
    $this->addFieldMapping('data_new_1346961121117', 'city__state');
    $this->addFieldMapping('data_new_1346961266027', 'number_of_tickets_purchased');
    $this->addFieldMapping('data_new_1346961351618', 'guests');

    $this->addUnmigratedDestinations(array(
      'data_new_1346959782966',
      'sid',
    ));
  }

  protected function query() {
    // We're only interested in one webform, with the known legacy nid 8346
    $query = Database::getConnection('default', 'legacy')
             ->select('webform_submissions', 's')
             ->fields('s', array('sid', 'uid', 'submitted', 'remote_addr'))
             ->condition('nid', 8346);
    return $query;
  }

  public function prepareRow($row) {
    $query = Database::getConnection('default', 'legacy')
             ->select('webform_submitted_data', 'd')
             ->fields('d', array('data'))
             ->condition('sid', $row->sid);
    $query->innerJoin('webform_component', 'c', 'd.nid=c.nid AND d.cid=c.cid');
    $query->fields('c', array('form_key'));
    $result = $query->execute();
    foreach ($result as $data_row) {
      $row->{$data_row->form_key} = $data_row->data;
    }
  }
}

Ain't that pretty, but it works.

note there is no migration path currently implemented for webforms themselves, I manually rebuilt them

Is this still the case? are we just dealing with submissions here?

Hi, Ryan Weal.

I haven't seen this format in use on any migrate modules.

You can simply debug this if you inspect MigrateDestinationWebformSubmission, because addFieldMapping() always is about destination object, so MigrateDestinationWebformSubmission has override for public function __construct, here method adds 'data_' prefix to the destination field name.

@Ryan Weal:
You just need to have a separate migration for each webform, same as you might do for dirfferent node types or different field collections etc. They can still be all together in the same module.

My last migration was just users from a spreadsheet and it required about a dozen migrations to get it all in due to profile2, field collection etc.

Wow, that sounds fantastic and will be great for the migrate suite.

Thanks for the work, I'm sure it will make my life easier at some point.

And for D7 -> D8, use https://www.drupal.org/project/webform_migrate