Snippet to allow setting BackWPup settings via wp-config.php constants

mainwp-backwpup.php

<?php 

/**
 * Allows setting BackWPup settings via wp-config.php constants
 *
 * Usefull for setting AWS S3 Access/Secret Keys in a constant instead of saving it in the database
 * Set the constant BACKWPUP_SETTINGS with configuration per jobid(!) like this:
 * ```php
 * define('BACKWPUP_SETTINGS', [
 *  '1' => [ // jobid
 *      's3accesskey' => 'accesskey',
 *      's3secretkey' => 'secretkey'
 *  ]
 * ]);
 * ```
 *
 * For available keys setup a job via UI and look at the serialized value in the database
 * s3region, s3accesskey, s3secretkey, s3bucket, s3dir
 *
 * Hooked on `site_option_backwpup_jobs`
 * because BackWPup uses site_option and site_option calls this filter even if it's not a multisite
 */
function mwp_mergeBackWPupSettings($value)
{
    if (!is_array($value)) {
        return $value;
    }

    if (!defined('BACKWPUP_SETTINGS') || !BACKWPUP_SETTINGS) {
        return $value;
    }

    foreach ($value as $k => $job) {
        $jobid = $job['jobid'];
        if (!isset(BACKWPUP_SETTINGS[$jobid])) {
            continue;
        }
        $value[$k] = array_merge($job, BACKWPUP_SETTINGS[$jobid]);
    }

    return $value;
}
add_filter('site_option_backwpup_jobs', 'mwp_mergeBackWPupSettings');

/**
 * Prevents from overwriting BackWPup settings defined via constants in the backend UI
 *
 * Loops through all jobs and optionKeys and checks if they are defined in the constant,
 * if yes an empty string is saved to the database
 *
 * Hooked on `pre_update_site_option_backwpup_jobs`
 * because BackWPup uses site_option and site_option calls this filter even if it's not a multisite
 */
function mwp_mergeBackWPupSettingsOnSave($value)
{
    if (!is_array($value)) {
        return $value;
    }

    if (!defined('BACKWPUP_SETTINGS') || !BACKWPUP_SETTINGS) {
        return $value;
    }

    foreach ($value as $k => $job) {
        $jobid = $job['jobid'];
        if (!isset(BACKWPUP_SETTINGS[$jobid])) {
            continue;
        }

        foreach ($job as $optionKey => $optionValue) {
            if (isset(BACKWPUP_SETTINGS[$jobid][$optionKey])) {
                $value[$k][$optionKey] = ''; // reset to empty
            }
        }
    }

    return $value;
}
add_filter('pre_update_site_option_backwpup_jobs', 'mwp_mergeBackWPupSettingsOnSave'); #

/**
 * Makes the constant-defined settings readonly/disabled in the backend UI
 *
 */
function mwp_printBackWPupJavaScript()
{

    $jobid = (int)$_GET['jobid'];
    if (!defined('BACKWPUP_SETTINGS') || !BACKWPUP_SETTINGS || !isset(BACKWPUP_SETTINGS[$jobid])) {
        return;
    }

    $readableKeys = array_keys(BACKWPUP_SETTINGS[$jobid]);
    if (empty($readableKeys)) {
        return;
    }
    $readableKeysSelectorString = implode(',', array_map(function ($k) {
        return "#$k, input[name='$k']";
    }, $readableKeys));
?>
    <script>
        (function($) {
            $("<?php echo $readableKeysSelectorString; ?>").attr("readonly", true).attr("disabled", true);
        })(jQuery)
    </script>
<?php
}
add_action('admin_footer-backwpup-pro_page_backwpupeditjob', 'mwp_printBackWPupJavaScript');
add_action('admin_footer-backwpup_page_backwpupeditjob', 'mwp_printBackWPupJavaScript');