Failure Handling with Actors

This lecture treats the most important characteristic of Actors, namely how they support handling failures in a principled fashion. Due to their encapsulation, failure is contained within the compartment of the system that is represented by each Actor. We therefore cover:

• how failure is communicated to a supervisor Actor in order to react to it
• how the supervisor decides its reaction
• helpful utilities offered by Akka for formulating supervision strategies
• how the various reactions (resume/restart/stop) affect the failed Actor
• how a restarted Actor can react to this event

We summarize these learnings by drawing a diagram of the Actor lifecycle.