id: mom_files
label: Files for Media
migration_group: mom
source:
  plugin: mom_files
  constants:
    source_base_path: 'sites/default/files/'
    old_files_path: 'sites/default/files/migration-files/'
process:
  filename: id
  source_full_path:
    -
      plugin: concat
      delimiter: /
      source:
        - constants/old_files_path
        - filepath
    -
      plugin: urlencode
  uri:
    plugin: file_copy
    source:
      - '@source_full_path'
      - uri
  created:
    plugin: callback
    source: created
    callable: strtotime
  changed: '@created'
  fid: id

destination:
  plugin: entity:file
  migration_dependencies:
    required:
      - mom_teachers

<?php

namespace Drupalmom_migratePluginmigratesource;

use DrupalmigratePluginmigratesourceSqlBase;
use DrupalmigrateRow;

/**
 * Source plugin for Mom files.
 *
 * @MigrateSource(
 *   id = "mom_files",
 * )
 */
class MomFiles extends SqlBase {

  /**
   * {@inheritdoc}
   */
  public function query() {
    $query = $this->select('images', 'im')
      ->fields('im', ['id', 'created']);

    return $query;
  }

  /**
   * {@inheritdoc}
   */
  public function prepareRow(Row $row) {
    if ($value = $row->getSourceProperty('id')) {
      $row->setSourceProperty('filename', $id);
      $row->setSourceProperty('uri', substr($id, -1) . '/');
    }
    return parent::prepareRow($row);
  }

  /**
   * {@inheritdoc}
   */
  public function fields() {
    return array(
      'id' => $this->t('File ID'),
      'filename' => $this->t('File name'),
      'uri' => $this->t('The URI to access the file'),
      'created' => $this->t('The time that the file was added.'),
    );
  }

  /**
   * {@inheritdoc}
   */
  public function getIds() {
    $ids['id']['type'] = 'integer';
    return $ids;
  }

}

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