I need to implement a way for customers to download their invoice as a PDF via a link. Magento will generate the download link for an order’s invoice, and that link is then handed off to a third-party email service (not Magento) which actually sends the email to the customer. So the click happens completely outside of any Magento session — the customer clicks the link straight from their inbox while logged out.
The link should work without login, should trigger a direct PDF download rather than opening a page, shouldn’t be easy to guess or tamper with (e.g. swapping the order ID to get someone else’s invoice), and ideally should expire after some time. What’s the best approach in Magento 2 to generate such a link, secure it, and serve the PDF on request?
