The Circuit Breaker pattern
One approach to FT involves retries, as we have just seen. But, when a failure due to communication with an external component is likely to be long-lasting, using a retry mechanism can affect the responsiveness of the application. We might be wasting time and resources trying to repeat a request that’s likely to fail. This is where another pattern can be useful: the Circuit Breaker pattern.
With the Circuit Breaker pattern, you wrap a fragile function call, or an integration point with an external service, in a special (circuit breaker) object, which monitors for failures. Once the failures reach a certain threshold, the circuit breaker trips and all subsequent calls to the circuit breaker return with an error, without the protected call being made at all.
Real-world examples
In life, we can think of a water or electricity distribution circuit where a circuit breaker plays an important role.
In software, a circuit breaker is used in the...
