Retries without duplicate sends: idempotency keys, atomic transitions and the double click

You send a request that triggers an e-mail, a push notification, an SMS or a payment. The connection drops. You do not know whether the server received it. Do you send it again? If you retry, you may send the message twice. If you don't, you may send it zero times. Over a network, the honest answer is that you must retry, so the real work is... Weiterlesen: Retries without duplicate sends: idempotency keys, atomic transitions…