src/Control/Middleware/HTTPCacheControlMiddleware.php
protected function generateExpiresHeader()
    {
        $maxAge = $this->getDirective('max-age');
        if ($maxAge === false) {
            return null;
        }

        // Add now to max-age to generate expires
        $expires = DBDatetime::now()->getTimestamp() + $maxAge;
        return gmdate('D, d M Y H:i:s', $expires) . ' GMT';
    }
protected function generateExpiresHeader()
    {
        $maxAge = $this->getDirective('max-age');
        if ($maxAge === false) {
            return null;
        }

        // Add now to max-age to generate expires
        $expires = DBDatetime::now()->getTimestamp() + $maxAge;
        return gmdate('D, d M Y H:i:s', $expires) . ' GMT';
    }
protected function generateExpiresHeader ( ) { $ maxAge = $ this -> getDirective ( 'max-age' ) ; if ( $ maxAge === false ) { return null ; } // Add now to max-age to generate expires $ expires = DBDatetime :: now ( ) -> getTimestamp ( ) + $ maxAge ; return gmdate ( 'D, d M Y H:i:s' , $ expires ) . ' GMT' ; }
Generate Expires http header

@return null|string
Generate Expires http header