What experience do you have in managing the file upload process?

In managing the file upload process, I used the following approaches:

• Validation of file type and size before upload to prevent uploading inappropriate or too large files.
• Using temporary directories to store uploaded files with subsequent verification and moving to permanent storage.
• Error handling and informing the user about the upload status.
• When necessary — implementing chunked upload for large files.

Example in PHP:

if (isset($_FILES['upload'])) {
    $file = $_FILES['upload'];
    if ($file['error'] === UPLOAD_ERR_OK) {
        $allowedTypes = ['image/jpeg', 'image/png'];
        if (in_array($file['type'], $allowedTypes) && $file['size'] < 5 * 1024 * 1024) {
            move_uploaded_file($file['tmp_name'], '/uploads/' . basename($file['name']));
            echo "File uploaded successfully.";
        } else {
            echo "Invalid file type or size.";
        }
    } else {
        echo "Error during file upload.";
    }
}