4 May 2017

Delivery Patterns

  • At-Most-Once : Messages may be lost, least desirable
  • At-Least-Once : Messages may be redelivered - no loss but may include duplicates
  • Exactly-Once : Messages are delivered once and only once - no loss and no duplicates, but difficult to guarantee

In order to manage state, messages may be stored in an embedded key-value store, a distributed file system, or use a higher level of abstraction.