Returns the extension for the given key

@param string $key
@return ArrayList
545294
public function getExtensions($key) {
		if ($this->extensions->has($key)) {
			return $this->extensions->get($key);
		}
		
		return [];
	}
453910
public function hGetAll($key) {
        return $this->send(['hgetall', $key], function ($response) {
            if ($response === null) {
                return null;
            }

            $size = \count($response);
            $result = [];

            for ($i = 0; $i < $size; $i += 2) {
                $result[$response[$i]] = $response[$i + 1];
            }

            return $result;
        });
    }
373184
public function downloadData($key)
    {
        $fileData = $this->getFileData($key);

        if (! $fileData)
            return false;

        return [
            'path' => $fileData['path'],
            'name' => $this->getLabel($key) . '.' . $fileData['extension']
        ];
    }
1006253
public function get($key)
    {
        $key = is_array($key) ? $key : [$key];
        $config = $this->data;
        while ($key) {
            $k = array_shift($key);
            $config = isset($config[$k]) ? $config[$k] : [];
        }
        return $config;
    }
1214596
public function keys(?string $key = null) : array
    {
        $value = $this->get($key);

        if (!is_array($value)) {
            throw new InvalidArgumentException(
                'method keys() should be called on array'
            );
        }

        return array_keys($value);
    }
992273
public function flatten(?string $key = null) : array
    {
        $array = new \RecursiveIteratorIterator(
            new \RecursiveArrayIterator((array) $this->get($key))
        );

        $tmp = [];
        foreach ($array as $value) {
            $tmp[] = $value;
        }

        return $tmp;
    }
992167
protected function getFileName($key)
    {
        $file = $this->getFilePath() . $this->encrypt($key) . $this->fileExtension;

        return $file;
    }
5233
public function paramsFor(string $key): array
    {
        $params = [];
        if (isset($this->params[$key])) {
            $params = $this->params[$key];
        }

        return $params;
    }
1035551
public function extract($key)
    {
        $extracted = [];

        foreach ($this->items as $item) {
            foreach (func_get_args() as $key) {
                if ($item instanceof CollectionInterface) {
                    $extracted[] = $item->get($key);
                } else if (is_object($item)) {
                    $extracted[] = $item->{$key};
                } else {
                    $extracted[] = $item[$key];
                }
            }
        }

        return $extracted;
    }
1361112
public function offsetGet($key)
    {
        $this->executeBeforeCallback();

        if (isset($this->items[$key])) {
            return $this->items[$key];
        }
    }
993404
protected function splitDictionaryRemainderAndPrefix(string $key): array
    {
        [$remainder, $prefix] = $this->splitRemainderAndPrefix($key);

        return [$this->dictionaries[$prefix], $remainder, $prefix];
    }
121497
protected function getNested(string $key)
    {
        $parts = explode('.', $key);
        $result = $this->settings[$parts[0]];

        for ($i = 1; $i < count($parts); ++$i) {
            $value = $parts[$i];

            if (is_array($result) && array_key_exists($value, $result)) {
                $result = $result[$value];
                continue;
            }

            $result = null;
            break;
        }

        return $result;
    }
22797
function findFieldByKey(string $key)
    {
        $this->checkFormIsBuilt();

        $fields = collect($this->fields);

        if(strpos($key, ".") !== false) {
            list($key, $itemKey) = explode(".", $key);
            $listField = $fields->where("key", $key)->first();

            return $listField->findItemFormFieldByKey($itemKey);
        }

        return $fields->where("key", $key)->first();
    }
966307
final protected function getArrayValue(string $key): array
    {
        $value = $this->getConfigValue($key);
        if (!$value || !\is_array($value)) {
            return [];
        }

        return $value;
    }
862497
protected function fetchKey($key)
    {
        if (str_contains($key, '.'))
        {
            $keys = explode('.', $key);
            $search = array_except($keys, 0);

            return array(array_get($keys, 0), implode('.', $search));
        }

        return array($key, null);
    }
357501
private function getNestedValueByKey($key)
    {
        if (isset($this->nestedKeyCache[$key])) {
            return $this->nestedKeyCache[$key];
        }

        // Check to see if this is targeting an instance of ArrayContainer and grab it from the nested container
        $keyParts = explode('.', $key);
        if ($this->get($keyParts[0]) instanceof self && $arrayContainer = $this->get($keyParts[0])) {
            array_shift($keyParts);
            /* @var ArrayContainer $arrayContainer */
            $value = $arrayContainer->get(implode('.', $keyParts));
        } else {
            $value = $this->items;
            foreach (explode('.', $key) as $keyPart) {
                if ((! is_array($value) || ! $value instanceof self)) {
                    if (is_object($value) && method_exists($value, 'arrayAccessByKey')) {
                        if ($value = $value->arrayAccessByKey($keyPart)) {
                            break;
                        } else {
                            return null;
                        }
                    }
                }

                if (! isset($value[$keyPart])) {
                    return null;
                }

                if (is_array($value[$keyPart]) && ! array_key_exists($keyPart, $value)) {
                    return null;
                }
                $value = $value[$keyPart];
            }
        }

        $this->nestedKeyCache[$key] = $value;

        return $value;
    }
1160528
protected function getIndex($key)
    {
        $index = array_search($key, $this->keys, true);

        if ($index === false) {
            throw new \InvalidArgumentException("Index not found in map keys");
        }

        return $index;
    }