Automatically update Advanced Custom Fields field groups via JSON

jp_sync_acf_fields.php

<?php
/**
 * Function that will automatically update ACF field groups via JSON file update.
 *
 * @link http://www.advancedcustomfields.com/resources/synchronized-json/
 */
function jp_sync_acf_fields($json_dirs) {
	$groups = acf_get_field_groups();
	if (empty($groups)) {
		return;
	}

	// find JSON field groups which have not yet been imported
	$sync 	= array();
	foreach ($groups as $group) {
		$local 		= acf_maybe_get($group, 'local', false);
		$modified 	= acf_maybe_get($group, 'modified', 0);
		$private 	= acf_maybe_get($group, 'private', false);

		// ignore DB / PHP / private field groups
		if ($local !== 'json' || $private) {
			// do nothing
		} elseif (! $group['ID']) {
			$sync[$group['key']] = $group;
		} elseif ($modified && $modified > get_post_modified_time('U', true, $group['ID'], true)) {
			$sync[$group['key']]  = $group;
		}
	}

	if (empty($sync)) {
		return;
	}
	foreach ($sync as $key => $group) { //foreach ($keys as $key) {
		// append fields
		if (acf_have_local_fields($key)) {
			$group['fields'] = acf_get_local_fields($key);
		}

		// import
		$field_group = acf_import_field_group($group);
	}

	// sync groups that have been deleted
	if (!is_array($json_dirs) || !$json_dirs) {
		throw new \Exception('JSON dirs missing');
	}
	$delete = array();
	foreach ($groups as $group) {
		$found = false;

		foreach ($json_dirs as $json_dir) {
			$json_file = rtrim($json_dir, '/') . '/' . $group['key'] . '.json';

			if (is_file($json_file)) {
				$found = true;

				break;
			}
		}

		if (!$found) {
			$delete[] = $group['key'];
		}
	}
	if (!empty($delete)) {
		foreach ($delete as $group_key) {
			acf_delete_field_group($group_key);
		}
	}
}

Hi, thanks for this good code.
I have modified it because that seems better to delete before to update. For example : you have three fields groups and so three json files and you delete this three json files, your code will be played until line 10 and will stop because $groups is empty. So in admin I still have three groups while there are no json files at all.
If I delete groups before update groups, I have no more groups in BO and no more json files.

That seems ok for you ? : https://gist.github.com/superpositif/85d14af60894520ab122f96e0fd046a6