degov-8.x-2.0/modules/degov_media_image/degov_media_image.module

<?php

use Drupal\degov_common\Common;

/**
 * Implements hook_preprocess().
 */
function degov_media_image_preprocess(&$variables, $hook, &$info) {
  // Add template suggestions and libraries implemented in this module.
  Common::addThemeSuggestions($variables, $hook, $info, [
    'module_name' => 'degov_media_image',
    'entity_type' => 'media',
    'entity_bundles' => ['image'],
    'entity_view_modes' => ['thumbnail', 'usage', 'preview', 'search', 'full', 'embedded'],
  ]);
}

/**
 * Implements hook_preprocess_type().
 */
function degov_media_image_preprocess_media__image(&$variables) {
  /** @var Drupal\media\Entity\Media $media */
  $media = $variables['elements']['#media'];
  $variables['created'] = $media->created->value;
  $variables['image_url'] = $media->url();

  // Add the download link only to full view mode.
  if (in_array($variables['elements']['#view_mode'], ['full', 'default'])) {
    // Add media type name to display.
    $bundle_definition = $media->getSource()->getPluginDefinition();
    $variables['content']['media_type_label'] = $bundle_definition['label'];
    // Check if the download of the video is allowed by media settings.
    $download_is_allowed = FALSE;
    if ($media->hasField('field_allow_download') && !$media->get('field_allow_download')->isEmpty()) {
      $download_is_allowed = $media->get('field_allow_download')->value ? TRUE : FALSE;
    }
    // If allowed let's prepare the links.
    if ($download_is_allowed) {
      // First check if the image is there.
      if (!$media->get('image')->isEmpty()) {
        /** @var \Drupal\file\FileInterface $sourceFile */
        $sourceFile = $media->get('image')->entity;
        $variables['content']['download'] = degov_common_file_download_render_array($sourceFile);
      }
      else {
        $variables['content']['download'] = [];
      }
    }
  }
}