file['query'] );

		if ( $file['query'] ) {
			return true;
		}

		return false;
	}

	/**
	 * Sets the current file extension and minify key
	 *
	 * @since 3.1
	 * @author Remy Perona
	 *
	 * @param string $extension Current file extension.
	 * @return void
	 */
	public function set_extension( $extension ) {
		$this->extension  = $extension;
		$this->minify_key = $this->options->get( 'minify_' . $this->extension . '_key' );
	}

	/**
	 * Gets the CDN zones.
	 *
	 * @since 3.1
	 * @author Remy Perona
	 *
	 * @return array
	 */
	public function get_zones() {
		return [ 'all', 'css_and_js', $this->extension ];

	}

	/**
	 * Gets the cache URL for the static file
	 *
	 * @since 3.1
	 * @author Remy Perona
	 *
	 * @param string $filename Filename for the static file.
	 * @return string
	 */
	protected function get_cache_url( $filename ) {
		$cache_url = $this->busting_url . $filename;

		switch ( $this->extension ) {
			case 'css':
				// This filter is documented in inc/classes/optimization/css/class-abstract-css-optimization.php.
				$cache_url = apply_filters( 'rocket_css_url', $cache_url );
				break;
			case 'js':
				// This filter is documented in inc/classes/optimization/css/class-abstract-js-optimization.php.
				$cache_url = apply_filters( 'rocket_js_url', $cache_url );
				break;
		}

		return $cache_url;
	}

	/**
	 * Gets content from an URL
	 *
	 * @since 3.1
	 * @author Remy Perona
	 *
	 * @param string $url URL to get the content from.
	 * @return string|bool
	 */
	protected function get_url_content( $url ) {
		$content  = wp_remote_retrieve_body( wp_remote_get( $url ) );

		if ( ! $content ) {
			return false;
		}

		return $content;
	}
}