src/Concerns/HasMiddleware.php
protected function enableMiddleware(string $key = '', string $group = null)
    {
        $middleware = $this->getMiddleware($key, $group);
        if ($middleware instanceof Enableable) {
            $middleware->enable();
        }
        return $this;
    }
protected function enableMiddleware(string $key = '', string $group = null)
    {
        $middleware = $this->getMiddleware($key, $group);
        if ($middleware instanceof Enableable) {
            $middleware->enable();
        }
        return $this;
    }
Enable the given middleware.

@param string $key
@param string|null $group
@return $this