Add WPML translations to WP2Static v7

wp2static_v7_wpml.php

<?php
/**
 * ------------------------------
 * | WP2Static WPML Integration |
 * ------------------------------
 * 
 * Important: The option WPML > Languages > "Adjust IDs for multilingual functionality" must be disabled.
 */

function wp2static_wpml_get_translated_posts_urls() {

    // Get all public custom post types
    $post_types = get_post_types( array( 'public' => true ), 'names' );

    // Fetch all post IDs across all translations and public post types
    $ids = get_posts( array(
        'fields'           => 'ids',
        'post_type'        => $post_types,
        'numberposts'      => -1,
        'suppress_filters' => true, // Get posts in all languages
    ) );

    $permalinks = array();

    foreach ( $ids as $id ) {
        $lang = apply_filters( 'wpml_post_language_details', NULL, $id );

        $permalink = get_permalink( $id );

        // Strip domain from permalink
        $permalink = parse_url( $permalink, PHP_URL_PATH );

        $permalinks[] = $permalink;
    }

    return $permalinks;
}

function wp2static_wpml_add_additional_urls( $url_queue ) {

    $translation_urls = wp2static_wpml_get_translated_posts_urls();

    $url_queue = array_merge(
        $url_queue,
        $translation_urls
    );

    return $url_queue;
}
add_filter( 'wp2static_modify_initial_crawl_list', 'wp2static_wpml_add_additional_urls' );

Please note: for this to work reliably, you need to go to WPML > Languages > and disable "Adjust IDs for multilingual functionality". Otherwise, the IDs get converted and you will be missing some pages during the crawl.

In fact.. if you disable that option you may not need this script at all.