Remove without field

[chrisvanpatten]

I did a bit of experimentation with a PR but wasn't quite able to get it to work, so I thought I'd take this to an issue to look for some ideas on how to implement :)

Given the sample document, I'm interested in being able to use remove() without providing a field, e.g. removing all matching paths.

Essentially supporting something like this:

$jsonObject = new JsonObject($json);

$jsonObject->remove("$..book[?(@.category == 'fiction')]");

$results = $jsonObject->toValue();

// $results with all fiction books removed.

I tried a simple unset($element); in the remove code but PHP's unset only unsets the reference, not the original value, so it doesn't quite work.

[Galbar]

Hi there! Sounds like a good addition.

Have you tried passing an optional parameter to getReal() stating the action, ie.remove, and have the remove logic happen when traversing the internal array? Instead of appending the match to $selection you could unset it from its parent.

[fbruno93]

Hi !
Here some workarround

$exploded = explode(".",  $fieldName);
$field = array_pop($exploded);
$imploded = implode(".", $exploded);
$jsonPath = "$";
if (!empty($imploded)) {
    $jsonPath .= ".".$imploded;
}
$jsonPathObject->remove($jsonPath, $field);

It's works on simple cases like $.store.bicycle.price

[artpol]

Hi! I solved this problem by comparing the found pointers with the pointers in the original data array. Minimal PHP version for this code is 8.1.

I made my class an inheritor of JsonObject and implemented the removePath($JsonPath) method in it, which can remove element just by path.

use JsonPath\JsonPath;

/**
 * Расширенный класс для удаления элементов из JSON
 */
class JsonObjectExtend extends \JsonPath\JsonObject
{
    /**
     * Удаляет элемент из массива согласно jsonPath
     *
     * @param string $json_path Запрос в формате jsonPath
     *
     * @return \JsonPath\JsonObject
     */
    public function removePath($json_path)
    {
        list($result, $_) = JsonPath::get($this->getValue(), $json_path);
        $this->recursiveRemove($this->getValue(), $result);
        return $this;
    }

    /**
     * Возвращает true, если $a и $b ссылаются на один и тот же участок памяти
     *
     * @param mixed $a переменная A
     * @param mixed $b переменная B
     * @return bool|void
     */
    protected function isSame(&$a, &$b) {
        $compare = [ &$a, &$b ];
        return
            \ReflectionReference::fromArrayElement($compare, 0)->getId() ===
            \ReflectionReference::fromArrayElement($compare, 1)->getId();
    }

    /**
     * Рекурсивно обходит исходный массив и удаляет в нем элементы,
     * которые содержатся в массиве $for_delete
     *
     * @param array $json исходный JSON
     * @param array $for_delete массив элементов, которые нужно удалить
     * @return void
     */
    protected function recursiveRemove(&$json, $for_delete)
    {
        if (is_array($json)) {
            $is_numeric_keys = array_is_list($json);
            $before_count = count($json);
            foreach($json as $key => &$value) {
                $deleted = false;
                foreach($for_delete as &$delete) {
                    if ($this->isSame($value, $delete)) {
                        unset($json[$key]);
                        $deleted = true;
                        break;
                    }
                }

                if (!$deleted && is_array($value)) {
                    $this->recursiveRemove($value, $for_delete);
                }
            }

            //Восстанавливаем порядок ключей в нумерованных массивах
            if ($is_numeric_keys && $before_count != count($json)) {
                $json = array_values($json);
            }
        }
    }
}

This library works very fast compared to others working with JSONPath, so I want it to live and develop. Thanks to the author.