Spring Cloud Openfeign on application starting time call openfeign with circuitbreaker and loadbalancer stuck main thread

example project test-cloud without circuitbreaker will working .

like issues #921 spring-framework issues

Feign client

package com.example.demo;

import org.springframework.cloud.openfeign.FeignClient;
import org.springframework.web.bind.annotation.GetMapping;

@FeignClient(value = "USER-TEST"
        ,fallbackFactory = TestClientFeignServiceFallBackFactory.class)
public interface TestClient {
    @GetMapping("/index")
    String test();
}

bean init

package com.example.demo;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

@Configuration
public class BeanConfig {
    @Autowired
    private TestClient testClient;

    @Bean
    public TestBean testBean() {
        System.out.println("start testBean");
        final String test = testClient.test();
        System.out.println("test = " + test);
        return new TestBean();
    }


}

the feign call will stuck until circuitbreaker timeout.

main thread waiting on condition

"main" prio=0 tid=0x0 nid=0x0 waiting on condition
     java.lang.Thread.State: WAITING
 on java.util.concurrent.CompletableFuture$Signaller@1fd76930
    at java.base@17.0.6/jdk.internal.misc.Unsafe.park(Native Method)
    at java.base@17.0.6/java.util.concurrent.locks.LockSupport.park(LockSupport.java:211)
    at java.base@17.0.6/java.util.concurrent.CompletableFuture$Signaller.block(CompletableFuture.java:1864)
    at java.base@17.0.6/java.util.concurrent.ForkJoinPool.unmanagedBlock(ForkJoinPool.java:3463)
    at java.base@17.0.6/java.util.concurrent.ForkJoinPool.managedBlock(ForkJoinPool.java:3434)
    at java.base@17.0.6/java.util.concurrent.CompletableFuture.waitingGet(CompletableFuture.java:1898)
    at java.base@17.0.6/java.util.concurrent.CompletableFuture.get(CompletableFuture.java:2072)
    at app//org.springframework.cloud.circuitbreaker.resilience4j.Resilience4jBulkheadProvider.lambda$decorateCallable$2(Resilience4jBulkheadProvider.java:148)
    at app//org.springframework.cloud.circuitbreaker.resilience4j.Resilience4jBulkheadProvider$$Lambda$825/0x00000008010b3b78.call(Unknown Source)
    at app//io.github.resilience4j.circuitbreaker.CircuitBreaker.lambda$decorateCallable$4(CircuitBreaker.java:168)
    at app//io.github.resilience4j.circuitbreaker.CircuitBreaker$$Lambda$826/0x00000008010b3da0.call(Unknown Source)
    at app//org.springframework.cloud.circuitbreaker.resilience4j.Resilience4JCircuitBreaker.getAndApplyFallback(Resilience4JCircuitBreaker.java:164)
    at app//org.springframework.cloud.circuitbreaker.resilience4j.Resilience4JCircuitBreaker.run(Resilience4JCircuitBreaker.java:125)
    at app//org.springframework.cloud.openfeign.FeignCircuitBreakerInvocationHandler.invoke(FeignCircuitBreakerInvocationHandler.java:113)
    at app/jdk.proxy2/jdk.proxy2.$Proxy77.test(Unknown Source)
    at app//com.example.demo.BeanConfig.testBean(BeanConfig.java:15)
    at app//com.example.demo.BeanConfig$$SpringCGLIB$$0.CGLIB$testBean$0(<generated>)
    at app//com.example.demo.BeanConfig$$SpringCGLIB$$FastClass$$1.invoke(<generated>)
    at app//org.springframework.cglib.proxy.MethodProxy.invokeSuper(MethodProxy.java:258)
    at app//org.springframework.context.annotation.ConfigurationClassEnhancer$BeanMethodInterceptor.intercept(ConfigurationClassEnhancer.java:331)
    at app//com.example.demo.BeanConfig$$SpringCGLIB$$0.testBean(<generated>)
    at java.base@17.0.6/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at java.base@17.0.6/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77)
    at java.base@17.0.6/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.base@17.0.6/java.lang.reflect.Method.invoke(Method.java:568)
    at app//org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:140)
    at app//org.springframework.beans.factory.support.ConstructorResolver.instantiate(ConstructorResolver.java:651)
    at app//org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:489)
    at app//org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1336)
    at app//org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1166)
    at app//org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:563)
    at app//org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:523)
    at app//org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:325)
    at app//org.springframework.beans.factory.support.AbstractBeanFactory$$Lambda$358/0x0000000800e18f68.getObject(Unknown Source)
    at app//org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:234)
    at app//org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:323)
    at app//org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199)
    at app//org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:254)
    at app//org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1441)
    at app//org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1348)
    at app//org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.resolveFieldValue(AutowiredAnnotationBeanPostProcessor.java:769)
    at app//org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:752)
    at app//org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:145)
    at app//org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessProperties(AutowiredAnnotationBeanPostProcessor.java:493)
    at app//org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1420)
    at app//org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:600)
    at app//org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:523)
    at app//org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:325)
    at app//org.springframework.beans.factory.support.AbstractBeanFactory$$Lambda$358/0x0000000800e18f68.getObject(Unknown Source)
    at app//org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:234)
    at app//org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:323)
    at app//org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199)
    at app//org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:973)
    at app//org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:946)
    at app//org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:616)
    at app//org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:146)
    at app//org.springframework.boot.SpringApplication.refresh(SpringApplication.java:753)
    at app//org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:455)
    at app//org.springframework.boot.SpringApplication.run(SpringApplication.java:323)
    at app//org.springframework.boot.SpringApplication.run(SpringApplication.java:1342)
    at app//org.springframework.boot.SpringApplication.run(SpringApplication.java:1331)
    at app//com.example.demo.HelloApplication.main(HelloApplication.java:22)

pool-2-thread-1 blocked

"pool-2-thread-1" prio=0 tid=0x0 nid=0x0 blocked
     java.lang.Thread.State: BLOCKED
 on java.util.concurrent.ConcurrentHashMap@2a631f26 owned by "main" Id=1
    at app//org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:217)
    at app//org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:323)
    at app//org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:274)
    at app//org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199)
    at app//org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:254)
    at app//org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1441)
    at app//org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1348)
    at app//org.springframework.beans.factory.support.ConstructorResolver.resolveAutowiredArgument(ConstructorResolver.java:911)
    at app//org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:789)
    at app//org.springframework.beans.factory.support.ConstructorResolver.autowireConstructor(ConstructorResolver.java:241)
    at app//org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.autowireConstructor(AbstractAutowireCapableBeanFactory.java:1356)
    at app//org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1193)
    at app//org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:563)
    at app//org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:523)
    at app//org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:325)
    at app//org.springframework.beans.factory.support.AbstractBeanFactory$$Lambda$358/0x0000000800e18f68.getObject(Unknown Source)
    at app//org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:234)
    at app//org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:323)
    at app//org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199)
    at app//org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:973)
    at app//org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:946)
    at app//org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:616)
    at app//org.springframework.cloud.context.named.NamedContextFactory.createContext(NamedContextFactory.java:138)
    at app//org.springframework.cloud.context.named.NamedContextFactory.getContext(NamedContextFactory.java:122)
    at app//org.springframework.cloud.context.named.NamedContextFactory.getInstances(NamedContextFactory.java:236)
    at app//org.springframework.cloud.openfeign.loadbalancer.FeignBlockingLoadBalancerClient.execute(FeignBlockingLoadBalancerClient.java:115)
    at app//feign.SynchronousMethodHandler.executeAndDecode(SynchronousMethodHandler.java:100)
    at app//feign.SynchronousMethodHandler.invoke(SynchronousMethodHandler.java:70)
    at app//org.springframework.cloud.openfeign.FeignCircuitBreakerInvocationHandler.lambda$asSupplier$1(FeignCircuitBreakerInvocationHandler.java:140)
    at app//org.springframework.cloud.openfeign.FeignCircuitBreakerInvocationHandler$$Lambda$807/0x00000008010ae378.get(Unknown Source)
    at app//org.springframework.cloud.circuitbreaker.resilience4j.Resilience4JCircuitBreaker$$Lambda$840/0x00000008010b86c8.call(Unknown Source)
    at java.base@17.0.6/java.util.concurrent.FutureTask.run(FutureTask.java:264)
    at java.base@17.0.6/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1136)
    at java.base@17.0.6/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:635)
    at java.base@17.0.6/java.lang.Thread.run(Thread.java:833)

Comment From: OlgaMaciaszek

The issue seems to be with the testClient.test() call being done from within the TestBean definition method (there's no issue while calling http GET :8082/index on a running application). This might be too early to use it. CC @ryanjbaxter.

Comment From: ryanjbaxter

It seems to be the combination of Spring Cloud OpenFeign and Spring Cloud CircuitBreaker that is the problem. If I just use Spring Cloud Circuit Breaker without the Feign client it works, and if I just use OpenFeign without Spring Cloud Circuit Breaker it works.

What is the real life use case here of making an HTTP request during bean initialization?

Comment From: sdandroid

It seems to be the combination of Spring Cloud OpenFeign and Spring Cloud CircuitBreaker that is the problem. If I just use Spring Cloud Circuit Breaker without the Feign client it works, and if I just use OpenFeign without Spring Cloud Circuit Breaker it works.

What is the real life use case here of making an HTTP request during bean initialization?

init SecurityFilterChain call HTTP request load rules from other service.

Comment From: ryanjbaxter

In general we discourage the use of Feign when initializing beans, see https://docs.spring.io/spring-cloud-openfeign/reference/spring-cloud-openfeign.html#early-initialization-errors We recommend you create the bean and then fetch the data when you actually need it.