php how to get image from url without knowing extension

Question

I would like to retrieve an image from a given url, i have the filename but the issue i have is that the extension is unknown. It could be either, jpg, gif or png.

This is how i have approached it but doesnt seem to be working:

$extensions = array('jpg', 'png', 'gif');
    foreach ($extensions as $ext) {
        if (file_exists('https://mytestimage.com/products/3c763dce-666b-4ba9-a05a-cca846391aea/thumb.' . $ext)) {
            echo 'Found filename.' . $ext;
            break;
        }
    }

Any suggestions?

Answer 1

Since the file is off-site, check if the URL exists instead.

$file = 'http://example.com/image.jpg';
$fileHeaders = @get_headers($file);
if( $fileHeaders[0]=='HTTP/1.1 404 Not Found')
{
    // File doesn't exist
}
else
{
    // File exists
}

You can apply this logic to your loop for the different extensions.

References: PHP.net & SO