Contributors: Teemu Suoranta

Tags: polylang, media, attachments, translations

License: GPLv2 or later

Polylang Translate existing media is an add-on for the multilingual WordPress plugin Polylang. This add-on let's you bulk translate and replace all existing media in content, featured image and meta fields you enable translations in media. This plugin is based on my other Polylang plugin polylang-copy-content.

When to use:

• When turning existing site to multi-lingual
• When enabling media translations when you already have media uploaded and added to content

Basic feature list:

• Translate all media (images and galleries) that are inside content, meta fields and featured image
• Takes care all post types (that are not 'attachment', 'revision', 'acf-field', 'acf-field-group', 'nav_menu_item', 'polylang_mo')
• Image translations are linked automatically
• You can add your own custom fields that have image IDs
• Uses Polylang's functions, no messing around

This is open source and I cannot give you any guarantees, though it has worked for me in many projects. Please, report issues and contribute!

How-to use (takes around 5 minutes):

• Take a backup of your database
• Download plugin and activate (you will need Polylang active)
• Enable Media translations in Polylang Settings
• Set all content without language to default language from "Languages" admin page
• Click "1. Translate the whole media library" from the admin notice
• Click through steps (50 posts at a time). Each step will take some time.
• Click "2. Translate existing images in content" from the admin notice
• Click through steps (50 posts at a time). Each step will take some time.
• Deactivate and delete plugin when you have gone through all the steps

Composer:

$ composer aucor/polylang-translate-existing-media

With composer.json:

{
  "require": {
    "aucor/polylang-translate-existing-media": "*"
  },
  "extra": {
    "installer-paths": {
      "htdocs/wp-content/plugins/{$name}/": ["type:wordpress-plugin"]
    }
  }
}

Add your own custom fields that have images saved as IDs:

function prefix_custom_fields_to_translate($custom_fields) {
	// return keys of your custom fields with image id
  return array(
    'my_custom_image_field',
    'other_custom_image_field'
  );
}
add_filter( 'polylang-translate-existing-media-custom-fields-with-image-id', 'prefix_custom_fields_to_translate' );

Issues:

(No known issues, yet)

To-do:

• Include terms and their custom fields
• Replacing count might be off, make it more informative

• PHP 7.2. compatibility

• New Feature: Translate whole media library
• New Feature: API for custom_fields that save the image as ID
• New Feature: Add filter to excluded post types polylang-translate-existing-media-skip-post-types
• Improvement: Include all post_status
• Bugfix: Don't copy featured image, just translate the existing one