Get response body from NoFallbackAvailableException in spring cloud circuit breaker resilience4j - spring-boot

Question

I want to call a third party API. I use spring cloud circuit breaker resilience4j.
Here is my service class :
package ir.co.isc.resilience4jservice.service;
import ir.co.isc.resilience4jservice.model.Employee;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.cloud.client.circuitbreaker.CircuitBreaker;
import org.springframework.cloud.client.circuitbreaker.CircuitBreakerFactory;
import org.springframework.cloud.client.circuitbreaker.NoFallbackAvailableException;
import org.springframework.stereotype.Service;
import org.springframework.web.client.RestTemplate;
#Service
public class EmployeeService {
#Autowired
private RestTemplate restTemplate;
#Autowired
private CircuitBreakerFactory circuitBreakerFactory;
public Employee getEmployee() {
try {
String url = "http://localhost:8090/employee";
CircuitBreaker circuitBreaker = circuitBreakerFactory.create("circuit-breaker");
return circuitBreaker.run(() -> restTemplate.getForObject(url, Employee.class));
} catch (NoFallbackAvailableException e) {
//I should extract error response body and do right action then return correct answer
return null;
}
}
}
ResilienceConfig:
package ir.co.isc.resilience4jservice.config;
import io.github.resilience4j.circuitbreaker.CircuitBreakerConfig;
import io.github.resilience4j.timelimiter.TimeLimiterConfig;
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 org.springframework.context.annotation.Configuration;
import java.time.Duration;
#Configuration
public class CircuitBreakerConfiguration {
#Bean
public Customizer<Resilience4JCircuitBreakerFactory> defaultCustomizer() {
CircuitBreakerConfig circuitBreakerConfig = CircuitBreakerConfig.custom()
.slidingWindowType(CircuitBreakerConfig.SlidingWindowType.COUNT_BASED)
.slidingWindowSize(10)
.minimumNumberOfCalls(10)
.failureRateThreshold(25)
.permittedNumberOfCallsInHalfOpenState(3)
.build();
TimeLimiterConfig timeLimiterConfig = TimeLimiterConfig.custom()
.timeoutDuration(Duration.ofSeconds(4))
.build();
return factory ->
factory.configureDefault(id -> new Resilience4JConfigBuilder(id)
.circuitBreakerConfig(circuitBreakerConfig)
.timeLimiterConfig(timeLimiterConfig)
.build());
}
}
in some situation third party api return ResponseEntity with statusCode = 500 and
body = {"errorCode":"CCBE"}.
response is look like this :
[503] during [POST] to [http://localhost:8090/employee]:[{"errorCode":"CCBE"}]
When I call this API and get internal server error with body, my catch block catchs api response.
In catch block I need retrieve response body and do some actions according to errorCode.
But I can not do this.
How can I extract body in this situation?