I allow free 30-day trials for my subscriptions which is managed by cancel_at_period_end flag set to true. I also have a webhook listening for customer.subscription.deleted event. In this hook I need the way to know that subscription was deleted by stripe after 30-days trial? How can I do that without storing extra information in my DB. I assume when it gets deleted the next is correct eventObject.ended_at === eventObject.trial_end? Is it really safe to use?
Yes, you can use eventObject.ended_at === eventObject.trial_end to check whether a subscription ended/was cancelled at the end of the subscriptions trial.