Spring-Cloud-Alibaba/spring-cloud-alibaba-docs/src/main/asciidoc/circuitbreaker-sentinel.adoc

=== Circuit Breaker: Spring Cloud Circuit Breaker With Sentinel & Configuring Sentinel Circuit Breakers

==== Default Configuration

To provide a default configuration for all of your circuit breakers create a `Customizer` bean that is passed a
`SentinelCircuitBreakerFactory` or `ReactiveSentinelCircuitBreakerFactory`.
The `configureDefault` method can be used to provide a default configuration.

====
[source,java]
----
@Bean
public Customizer<SentinelCircuitBreakerFactory> defaultCustomizer() {
	return factory -> factory.configureDefault(id -> new SentinelConfigBuilder(id)
			.build());
}
----
====

You can choose to provide default circuit breaking rules via `SentinelConfigBuilder#rules(rules)`.
You can also choose to load circuit breaking rules later elsewhere using
`DegradeRuleManager.loadRules(rules)` API of Sentinel, or via Sentinel dashboard.

===== Reactive Example

====
[source,java]
----
@Bean
public Customizer<ReactiveSentinelCircuitBreakerFactory> defaultCustomizer() {
	return factory -> factory.configureDefault(id -> new SentinelConfigBuilder(id)
			.build());
}
----
====

==== Specific Circuit Breaker Configuration

Similarly to providing a default configuration, you can create a `Customizer` bean this is passed a
`SentinelCircuitBreakerFactory`.

====
[source,java]
----
@Bean
public Customizer<SentinelCircuitBreakerFactory> slowCustomizer() {
	String slowId = "slow";
	List<DegradeRule> rules = Collections.singletonList(
		new DegradeRule(slowId).setGrade(RuleConstant.DEGRADE_GRADE_RT)
			.setCount(100)
			.setTimeWindow(10)
		);
	return factory -> factory.configure(builder -> builder.rules(rules), slowId);
}
----
====

===== Reactive Example

====
[source,java]
----
@Bean
public Customizer<ReactiveSentinelCircuitBreakerFactory> customizer() {
	List<DegradeRule> rules = Collections.singletonList(
		new DegradeRule().setGrade(RuleConstant.DEGRADE_GRADE_RT)
			.setCount(100)
			.setTimeWindow(10)
		);
	return factory -> factory.configure(builder -> builder.rules(rules), "foo", "bar");
}
----
====