Convert an ACF Field Group from PHP to ACF-JSON

acf-field-group-php-to-json.php

<?php
add_action( 'acf/init', function() {
	// Get all the local field groups and loop through them for processing.
	$field_groups = acf_get_local_field_groups();

	foreach ( $field_groups as $group ) {
		// If the field group has fields, load them into the 'fields' key.
		if ( acf_have_local_fields( $group['key'] ) ) {
			$group_fields = acf_get_local_fields( $group['key'] );

			foreach ( $group_fields as $field_key => $field_options ) {
				if ( $field_options['type'] !== 'repeater' ) {
					continue;
				}

				if ( acf_have_local_fields( $field_key ) ) {
					$group_fields[ $field_key ]['sub_fields'] = acf_get_local_fields( $field_key );
				}
			}

			$group['fields'] = $group_fields;
		}

		// Write the group's JSON file.
		acf_write_json_field_group( $group );
	}
}, 99 );