Lesson 03.5
Dead-letter queues & poison messages
A poison message is one that fails every time it is processed; a dead-letter queue sets such messages aside after a few tries so the rest can keep flowing.
One bad order in the pile
Ava works through the cookie orders on the computer one at a time, in order. Order ② has a smudged address the computer can't read, so it fails every time Ava tries it.
What should Ava do with it, so orders ③ to ⑧ still get done?
In this lesson you'll
- 1Watch the problem pile at work.
- 2Guess what happens if Ava keeps trying forever.
- 3Find the rule that loses nothing and never gets stuck.