Spring boot circuit breaker

README.md

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+On first Hit:
+
+<img width="746" alt="image" src="https://github.com/rahulvaish/SpringBoot-Java/assets/689226/fe749372-b6b8-45b9-8b42-6c82309c801f">
+<img width="488" alt="image" src="https://github.com/rahulvaish/SpringBoot-Java/assets/689226/06da2867-7279-4a96-a31e-88a4b51067ac">
+
+____________________________________________________________________
+
+
+When Service B is down:
+<br>
+Because sliding-window-size: 10 and failure-rate-threshold: 50 that means out of 10 if 5 failed the circuit will jump to Open state
+<img width="745" alt="image" src="https://github.com/rahulvaish/SpringBoot-Java/assets/689226/ca81ccae-1200-4d41-894d-338437e38f02">
+<img width="532" alt="image" src="https://github.com/rahulvaish/SpringBoot-Java/assets/689226/2fd290af-c52c-4210-978c-0621458dd849">
+
+____________________________________________________________________
+
+
+In Open state, after 5 seconds it turns into Half Open state, now try 3 times (because wait-duration-in-open-state: 5000ms and  permitted-number-of-calls-in-half-open-state: 3)
+<br>
+If 2/3 pass -> Circuit Open, else, Circuit Closed.
+<br>
+In my case, I kept Service B shut, so circuit got open:
+<br>
+<img width="519" alt="image" src="https://github.com/rahulvaish/SpringBoot-Java/assets/689226/72409ff0-eda0-4099-88fd-165b57720e2b">
+
+
+____________________________________________________________________
+
+Now, I turned the ServiceB up and running, and after 5 seconds (In Half Open state) I tried 3 times (because wait-duration-in-open-state: 5000ms and  permitted-number-of-calls-in-half-open-state: 3)
+<br>
+All 3/3 pass -> Circuit Closed.
+<img width="749" alt="image" src="https://github.com/rahulvaish/SpringBoot-Java/assets/689226/19049681-505e-4984-8dc9-5250efee70df">
+<img width="509" alt="image" src="https://github.com/rahulvaish/SpringBoot-Java/assets/689226/2a205c3f-fd31-45ad-9766-00ed37c18fab">
+
+Note: While n/3 hits were in attempt the circuit was in half open state.

ServiceA/.gitignore

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+HELP.md
+.gradle
+build/
+!gradle/wrapper/gradle-wrapper.jar
+!**/src/main/**/build/
+!**/src/test/**/build/
+
+### STS ###
+.apt_generated
+.classpath
+.factorypath
+.project
+.settings
+.springBeans
+.sts4-cache
+bin/
+!**/src/main/**/bin/
+!**/src/test/**/bin/
+
+### IntelliJ IDEA ###
+.idea
+*.iws
+*.iml
+*.ipr
+out/
+!**/src/main/**/out/
+!**/src/test/**/out/
+
+### NetBeans ###
+/nbproject/private/
+/nbbuild/
+/dist/
+/nbdist/
+/.nb-gradle/
+
+### VS Code ###
+.vscode/

ServiceA/build.gradle

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+plugins {
+	id 'org.springframework.boot' version '2.7.5'
+	id 'io.spring.dependency-management' version '1.0.15.RELEASE'
+	id 'java'
+}
+
+group = 'com.example.serviceA'
+version = '0.0.1-SNAPSHOT'
+sourceCompatibility = '17'
+
+repositories {
+	mavenCentral()
+}
+
+ext {
+	set('springCloudVersion', "2021.0.4")
+}
+
+dependencies {
+	implementation 'org.springframework.boot:spring-boot-starter-web'
+	implementation 'org.springframework.cloud:spring-cloud-starter-circuitbreaker-resilience4j'
+	testImplementation 'org.springframework.boot:spring-boot-starter-test'
+	implementation group: 'org.springframework.boot', name: 'spring-boot-starter-aop', version: '2.7.5'
+
+	implementation group: 'org.springframework.boot', name: 'spring-boot-starter-actuator', version: '2.7.5'
+}
+
+dependencyManagement {
+	imports {
+		mavenBom "org.springframework.cloud:spring-cloud-dependencies:${springCloudVersion}"
+	}
+}
+
+tasks.named('test') {
+	useJUnitPlatform()
+}

ServiceA/gradle/wrapper/gradle-wrapper.properties

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+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-7.5.1-bin.zip
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists