Convert Advanced Custom Fields Pro configuration from PHP to JSON.

acf-php-to-json.php

<?php
/**
 * Plugin Name: Convert ACF PHP to JSON
 * Description: Convert Advanced Custom Fields Pro configuration from PHP to JSON.
 */

namespace ConvertAcfPhpToJson;

/**
 * Add submenu item under 'Custom Fields'
 */
function admin_menu() {
    add_submenu_page('edit.php?post_type=acf-field-group', 'Convert PHP fields to JSON', 'PHP to JSON', 'manage_options', 'acf-php-to-json', __NAMESPACE__ . '\\admin_page');
}
add_action('admin_menu', __NAMESPACE__ . '\\admin_menu', 20);

/**
 * Output the admin page
 */
function admin_page() {
    ?>
    <div class="wrap">
        <h1>Convert PHP fields to JSON</h1>
        <?php

        if (!isset($_GET['continue']) || $_GET['continue'] !== 'true') {
            admin_page_intro();
        }
        else {
            admin_page_convert();
        }
        ?>
    </div>
    <?php
}

/**
 * Output the introductory page
 */
function admin_page_intro() {
    $groups = get_groups_to_convert();

    if (empty($groups)) {
        echo '<p>No PHP field group configuration found. Nothing to convert.</p>';
        return;
    }
    else {
        echo sprintf('<p>%d field groups will be converted from PHP to JSON configuration.</p>', count($groups));
        echo '<a href="edit.php?post_type=acf-field-group&page=acf-php-to-json&continue=true" class="button button-primary">Convert Field Groups</a>';
    }
}

/**
 * Convert the field groups and output the conversion page
 */
function admin_page_convert() {
    $groups = get_groups_to_convert();

    echo sprintf('<p>Converting %d field groups from PHP to JSON configuration...</p>', count($groups));

    echo '<ol>';
    foreach ($groups as $group) {
        if (convert_group($group)) {
            echo sprintf('<li>Converted: <strong>%s</strong> (%s)</li>', $group['title'], $group['key']);
        }
        else {
            echo sprintf('<li><strong>Failed to convert: %s</strong> (%s)</li>', $group['title'], $group['key']);
        }
    }
    echo '</ol>';

    echo '<p>Done. Now remove the PHP field group configuration.</p>';
}

/**
 * Get the PHP field groups which will be converted.
 *
 * @return array
 */
function get_groups_to_convert() {
    $groups = acf_get_local_field_groups();
    if (!$groups) return [];
    return array_filter($groups, function($group) {
        return $group['local'] == 'php';
    });
}

/**
 * Convert a field group to JSON
 *
 * @param array $group
 * @return bool
 */
function convert_group($group) {
    $group['fields'] = acf_get_fields($group['key']);
    return acf_write_json_field_group($group);
}

This seemed to work but it looks like it took clone fields and compressed them somehow - the exported PHP is different and results in a structure that causes all sorts of problems.
Before import:

			'label' => 'Accessibility',
			'name' => 'accessability',
			'type' => 'clone',
			'instructions' => '',
			'required' => 0,
			'conditional_logic' => 0,
			'wrapper' => array(
				'width' => '',
				'class' => '',
				'id' => '',
			),
			'clone' => array(
				0 => 'field_5b058cc491a9c',
			),
			'display' => 'seamless',
			'layout' => 'block',
			'prefix_label' => 1,
			'prefix_name' => 1,

After import and re-export:

			'label' => 'Accessibility Accordion Items',
			'name' => 'accessability_items',
			'type' => 'repeater',
			'instructions' => '',
			'required' => 1,
			'conditional_logic' => 0,
			'wrapper' => array(
				'width' => '',
				'class' => '',
				'id' => '',
			),
			'collapsed' => 'field_5b058cd191a9d',
			'min' => 1,
			'max' => 0,
			'layout' => 'block',
			'button_label' => 'Add Item',
			'_clone' => 'field_5df01d8a5312e',
			'__key' => 'field_5b058cc491a9c',
			'__name' => 'items',
			'__label' => 'Accordion Items',
			'sub_fields' => array(
			),

Noting that the original PHP was written awhile back and possibly a few minor versions ago, so it's possible that the format has changed in the meantime - however the expectation is that the field machine names (by which I'm actually pulling the field values) shouldn't change, but they are and that breaks a lot of stuff. Anyone else having similar issues?

NOTE: Getting this error for each group that is imported:

Undefined index: ID in /wp-content/plugins/advanced-custom-fields-pro/includes/local-json.php on line 215

This just seems to be a check-for-existing-fieldgroup-post that isn't properly null-coalesced, so not crucial to the issue above.

Hi @bigheadzach

I haven't used WordPress for several years now, so am not best placed to help figure out why that's happened in your case. However, I wonder if it could be related to the issue AdvancedCustomFields/acf#266.

Within this plugin, the conversion from PHP to JSON happens in the convert_group function:

function convert_group($group) {
    $group['fields'] = acf_get_fields($group['key']);
    return acf_write_json_field_group($group);
}

The functions acf_get_fields and acf_write_json_field_group are provided by ACF itself. This plugin essentially just acts as the glue between those two functions – but it doesn't perform any conversion logic of its own, as that's all handled by those ACF functions.

I hope that helps!

Thanks a lot!!

@ollietreend Thank you for this!

I'm getting failed to convert error. I've check acf json and file permission already.