From e5b607eb9dd4f1110a1efcca8a23c0a8b2f290b3 Mon Sep 17 00:00:00 2001
From: Rikako Wu <496063163@qq.com>
Date: Fri, 21 Apr 2023 15:29:31 +0800
Subject: [PATCH] =?UTF-8?q?spring=20cloud=20circuit=20breaker=E6=96=87?=
 =?UTF-8?q?=E6=A1=A3=E9=98=85=E8=AF=BB?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .../Spring Cloud Circuit Breaker.md           | 78 +++++++++++++++++++
 1 file changed, 78 insertions(+)

diff --git a/spring/Spring Cloud/Spring Cloud Circuit Breaker.md b/spring/Spring Cloud/Spring Cloud Circuit Breaker.md
index 7541639..ea35c51 100644
--- a/spring/Spring Cloud/Spring Cloud Circuit Breaker.md	
+++ b/spring/Spring Cloud/Spring Cloud Circuit Breaker.md	
@@ -20,3 +20,81 @@ public Customizer<Resilience4JCircuitBreakerFactory> defaultCustomizer() {
 ```
 ### 自定义ExecutorService
 如果想要自定义执行circuit breaker的`ExecutorService`，可以通过Resilience4JCircuitBreakerFactor来指定。  
+例如，想要指定一个context aware ExecutorService，可以按如下所示：
+```java
+@Bean
+public Customizer<ReactiveResilience4JCircuitBreakerFactory> defaultCustomizer() {
+    return factory -> {
+        ContextAwareScheduledThreadPoolExecutor executor = ContextAwareScheduledThreadPoolExecutor.newScheduledThreadPool().corePoolSize(5)
+            .build();
+        factory.configureExecutorService(executor);
+    };
+}
+```
+### 指定Circuit Breaker 配置
+类似为所有Circuit Breakers指定默认配置，也能以如下方式为特定Circuit Breaker指定配置：
+```java
+@Bean
+public Customizer<Resilience4JCircuitBreakerFactory> slowCustomizer() {
+    return factory -> factory.configure(builder -> builder.circuitBreakerConfig(CircuitBreakerConfig.ofDefaults())
+            .timeLimiterConfig(TimeLimiterConfig.custom().timeoutDuration(Duration.ofSeconds(2)).build()), "slow");
+}
+```
+### Circuit Breaker属性配置
+可以在配置文件中指定`CircuitBreaker`和`TimeLimiter`配置，配置文件中指定的配置比Customizer中指定的配置优先级更高。  
+优先级从上到下递减：
+- 方法级别(id)配置 - 针对指定的方法或操作
+- service级别（group）配置 - 针对指定应用的service或操作
+- 全局默认配置
+
+#### 全局默认
+```yml
+resilience4j.circuitbreaker:
+    configs:
+        default:
+            registerHealthIndicator: true
+            slidingWindowSize: 50
+
+resilience4j.timelimiter:
+    configs:
+        default:
+            timeoutDuration: 5s
+            cancelRunningFuture: true
+```
+#### Configs Properties Configuration
+```yml
+resilience4j.circuitbreaker:
+    configs:
+        groupA:
+            registerHealthIndicator: true
+            slidingWindowSize: 200
+
+resilience4j.timelimiter:
+    configs:
+        groupC:
+            timeoutDuration: 3s
+            cancelRunningFuture: true
+```
+#### 实例属性设置
+```yml
+resilience4j.circuitbreaker:
+ instances:
+     backendA:
+         registerHealthIndicator: true
+         slidingWindowSize: 100
+     backendB:
+         registerHealthIndicator: true
+         slidingWindowSize: 10
+         permittedNumberOfCallsInHalfOpenState: 3
+         slidingWindowType: TIME_BASED
+         recordFailurePredicate: io.github.robwin.exception.RecordFailurePredicate
+
+resilience4j.timelimiter:
+ instances:
+     backendA:
+         timeoutDuration: 2s
+         cancelRunningFuture: true
+     backendB:
+         timeoutDuration: 1s
+         cancelRunningFuture: false
+```
\ No newline at end of file