From 88cc732dc7bfffba9f086bd0d77f0487b56bd0bb Mon Sep 17 00:00:00 2001 From: Catalin Burcea Date: Thu, 9 Apr 2020 10:30:04 +0300 Subject: [PATCH] BAEL-3649 Quick Guide to Spring Cloud Circuit Breaker (#8819) --- .../spring-cloud-circuit-breaker/README.md | 5 ++ .../spring-cloud-circuit-breaker/pom.xml | 55 ++++++++++++++ .../baeldung/circuitbreaker/AlbumService.java | 40 +++++++++++ .../baeldung/circuitbreaker/Controller.java | 18 +++++ .../baeldung/circuitbreaker/SpringApp.java | 71 +++++++++++++++++++ .../main/resources/fallback-album-list.json | 12 ++++ 6 files changed, 201 insertions(+) create mode 100644 spring-cloud/spring-cloud-circuit-breaker/README.md create mode 100644 spring-cloud/spring-cloud-circuit-breaker/pom.xml create mode 100644 spring-cloud/spring-cloud-circuit-breaker/src/main/java/com/baeldung/circuitbreaker/AlbumService.java create mode 100644 spring-cloud/spring-cloud-circuit-breaker/src/main/java/com/baeldung/circuitbreaker/Controller.java create mode 100644 spring-cloud/spring-cloud-circuit-breaker/src/main/java/com/baeldung/circuitbreaker/SpringApp.java create mode 100644 spring-cloud/spring-cloud-circuit-breaker/src/main/resources/fallback-album-list.json diff --git a/spring-cloud/spring-cloud-circuit-breaker/README.md b/spring-cloud/spring-cloud-circuit-breaker/README.md new file mode 100644 index 0000000000..040eb0ccee --- /dev/null +++ b/spring-cloud/spring-cloud-circuit-breaker/README.md @@ -0,0 +1,5 @@ +## Spring Cloud Circuit Breaker + +This module contains articles about Spring Cloud Circuit Breaker + +### Relevant Articles: diff --git a/spring-cloud/spring-cloud-circuit-breaker/pom.xml b/spring-cloud/spring-cloud-circuit-breaker/pom.xml new file mode 100644 index 0000000000..188fc4bf8e --- /dev/null +++ b/spring-cloud/spring-cloud-circuit-breaker/pom.xml @@ -0,0 +1,55 @@ + + + 4.0.0 + spring-cloud-circuit-breaker + spring-cloud-gateway + jar + + + com.baeldung.spring.cloud + spring-cloud + 1.0.0-SNAPSHOT + .. + + + + + spring-snapshots + Spring Snapshots + https://repo.spring.io/libs-snapshot + + true + + + false + + + + + + + + org.springframework.boot + spring-boot-dependencies + 2.2.4.RELEASE + pom + import + + + + + + + org.springframework.cloud + spring-cloud-starter-circuitbreaker-resilience4j + 1.0.2.RELEASE + + + org.springframework.boot + spring-boot-starter-web + + + + diff --git a/spring-cloud/spring-cloud-circuit-breaker/src/main/java/com/baeldung/circuitbreaker/AlbumService.java b/spring-cloud/spring-cloud-circuit-breaker/src/main/java/com/baeldung/circuitbreaker/AlbumService.java new file mode 100644 index 0000000000..67163c8c9a --- /dev/null +++ b/spring-cloud/spring-cloud-circuit-breaker/src/main/java/com/baeldung/circuitbreaker/AlbumService.java @@ -0,0 +1,40 @@ +package com.baeldung.circuitbreaker; + +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; +import org.springframework.beans.factory.annotation.Autowired; +import org.springframework.cloud.client.circuitbreaker.CircuitBreaker; +import org.springframework.cloud.client.circuitbreaker.CircuitBreakerFactory; +import org.springframework.stereotype.Service; +import org.springframework.web.client.RestTemplate; + +import java.nio.file.Files; +import java.nio.file.Paths; + +@Service +public class AlbumService { + + private static final Logger LOGGER = LoggerFactory.getLogger(AlbumService.class); + + @Autowired + private CircuitBreakerFactory circuitBreakerFactory; + + private RestTemplate restTemplate = new RestTemplate(); + + public String getAlbumList() { + CircuitBreaker circuitBreaker = circuitBreakerFactory.create("circuitbreaker"); + String url = "https://jsonplaceholder.typicode.com/albums"; + + return circuitBreaker.run(() -> restTemplate.getForObject(url, String.class), throwable -> getDefaultAlbumList()); + } + + private String getDefaultAlbumList() { + try { + return new String(Files.readAllBytes(Paths.get(getClass().getClassLoader().getResource("fallback-album-list.json").toURI()))); + } catch (Exception e) { + LOGGER.error("error occurred while reading the file", e); + } + return null; + } + +} diff --git a/spring-cloud/spring-cloud-circuit-breaker/src/main/java/com/baeldung/circuitbreaker/Controller.java b/spring-cloud/spring-cloud-circuit-breaker/src/main/java/com/baeldung/circuitbreaker/Controller.java new file mode 100644 index 0000000000..10f7c57a7a --- /dev/null +++ b/spring-cloud/spring-cloud-circuit-breaker/src/main/java/com/baeldung/circuitbreaker/Controller.java @@ -0,0 +1,18 @@ +package com.baeldung.circuitbreaker; + +import org.springframework.beans.factory.annotation.Autowired; +import org.springframework.web.bind.annotation.GetMapping; +import org.springframework.web.bind.annotation.RestController; + +@RestController +public class Controller { + + @Autowired + private AlbumService service; + + @GetMapping("/albums") + public String albums() { + return service.getAlbumList(); + } + +} \ No newline at end of file diff --git a/spring-cloud/spring-cloud-circuit-breaker/src/main/java/com/baeldung/circuitbreaker/SpringApp.java b/spring-cloud/spring-cloud-circuit-breaker/src/main/java/com/baeldung/circuitbreaker/SpringApp.java new file mode 100644 index 0000000000..f891e7693f --- /dev/null +++ b/spring-cloud/spring-cloud-circuit-breaker/src/main/java/com/baeldung/circuitbreaker/SpringApp.java @@ -0,0 +1,71 @@ +package com.baeldung.circuitbreaker; + +import io.github.resilience4j.circuitbreaker.CircuitBreakerConfig; +import io.github.resilience4j.timelimiter.TimeLimiterConfig; +import org.springframework.boot.SpringApplication; +import org.springframework.boot.autoconfigure.SpringBootApplication; +import org.springframework.cloud.circuitbreaker.resilience4j.Resilience4JCircuitBreakerFactory; +import org.springframework.cloud.circuitbreaker.resilience4j.Resilience4JConfigBuilder; +import org.springframework.cloud.client.circuitbreaker.Customizer; +import org.springframework.context.annotation.Bean; + +import java.time.Duration; + +@SpringBootApplication +public class SpringApp { + + public static void main(String[] args) { + SpringApplication.run(SpringApp.class, args); + } + + @Bean + public Customizer globalCustomConfiguration() { + TimeLimiterConfig timeLimiterConfig = TimeLimiterConfig.custom() + .timeoutDuration(Duration.ofSeconds(4)) + .build(); + CircuitBreakerConfig circuitBreakerConfig = CircuitBreakerConfig.custom() + .failureRateThreshold(50) + .waitDurationInOpenState(Duration.ofMillis(1000)) + .slidingWindowSize(2) + .build(); + + return factory -> factory.configureDefault(id -> new Resilience4JConfigBuilder(id) + .timeLimiterConfig(timeLimiterConfig) + .circuitBreakerConfig(circuitBreakerConfig) + .build()); + } + + @Bean + public Customizer specificCustomConfiguration1() { + + TimeLimiterConfig timeLimiterConfig = TimeLimiterConfig.custom() + .timeoutDuration(Duration.ofSeconds(4)) + .build(); + CircuitBreakerConfig circuitBreakerConfig = CircuitBreakerConfig.custom() + .failureRateThreshold(50) + .waitDurationInOpenState(Duration.ofMillis(1000)) + .slidingWindowSize(2) + .build(); + + return factory -> factory.configure(builder -> builder.circuitBreakerConfig(circuitBreakerConfig) + .timeLimiterConfig(timeLimiterConfig).build(), "circuitBreaker"); + } + + @Bean + public Customizer specificCustomConfiguration2() { + + TimeLimiterConfig timeLimiterConfig = TimeLimiterConfig.custom() + .timeoutDuration(Duration.ofSeconds(4)) + .build(); + CircuitBreakerConfig circuitBreakerConfig = CircuitBreakerConfig.custom() + .failureRateThreshold(50) + .waitDurationInOpenState(Duration.ofMillis(1000)) + .slidingWindowSize(2) + .build(); + + return factory -> factory.configure(builder -> builder.circuitBreakerConfig(circuitBreakerConfig) + .timeLimiterConfig(timeLimiterConfig).build(), + "circuitBreaker1", "circuitBreaker2", "circuitBreaker3"); + } + +} diff --git a/spring-cloud/spring-cloud-circuit-breaker/src/main/resources/fallback-album-list.json b/spring-cloud/spring-cloud-circuit-breaker/src/main/resources/fallback-album-list.json new file mode 100644 index 0000000000..001df7610a --- /dev/null +++ b/spring-cloud/spring-cloud-circuit-breaker/src/main/resources/fallback-album-list.json @@ -0,0 +1,12 @@ +[ + { + "userId": 1, + "id": 1, + "title": "quidem molestiae enim" + }, + { + "userId": 1, + "id": 2, + "title": "sunt qui excepturi placeat culpa" + } +] \ No newline at end of file