idempotency

What are best practices for activation/registration/password-reset links in emails with nonce

Applications send out emails to verify user accounts or reset a password. I believe the following is the way it should be and I am asking for references and implementations. If an application has to send out a link in an email to verify the user's address, according to my view, the link and the application's processing of the link shoul...

How to ensure message idempotency with multiple competing consumers?

I have multiple distributed competing consumers each pulling messages off the same (transactional) queue. I want to implement each consumer as an Idempotent Receiver so I never process the same message more than once (across all consumers) even if a duplicate arrives. How can I accomplish this with multiple consumers? My first thought i...