private function getCacheKey(ServerRequestInterface $request)
    {
        $id = base64_encode((string) $request->getUri());
        $hints = $this->getClientHints($request);

        if ($hints) {
            $id .= '.'.base64_encode(json_encode($hints));
        }

        return $id;
    }
private function getCacheKey(ServerRequestInterface $request)
    {
        $id = base64_encode((string) $request->getUri());
        $hints = $this->getClientHints($request);

        if ($hints) {
            $id .= '.'.base64_encode(json_encode($hints));
        }

        return $id;
    }
private function getCacheKey ( ServerRequestInterface $ request ) { $ id = base64_encode ( ( string ) $ request -> getUri ( ) ) ; $ hints = $ this -> getClientHints ( $ request ) ; if ( $ hints ) { $ id .= '.' . base64_encode ( json_encode ( $ hints ) ) ; } return $ id ; }
Generates the key used to save the image in cache.

@param ServerRequestInterface $request

@return string
Generates the key used to save the image in cache .