I have a script that takes an image and generates a resized version.
i.e. requesting /images/50x50-logo.png will call image-conroller.php which will then return a 50x50 version of logo.png
The image is returned using;
header('Content-Type: '.mime_content_type($sOutputPath));
readfile($sOutputPath);
As far as I'm aware, using this method to return the image, there is no safe way to check if the user already has a cached a version of this image. So how am I supposed to know if to send a 304 or serve the image?
Would someone please mind explaing if it's possible to achieve this. Or provide some direction to a soloution/workaround?
N.B. I can't think of a suitable title, any suggestions/edits would be apprecaited.