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javahystrixcircuit-breaker

How to force a Hystrix circuit breaker open?


I would like to programmatically force a circuit breaker to open for a particular group. I thought I might be able to do that by setting the config on a command in a group to force open, and running that command. However, that doesn't seem to work. Is this possible? Should I take a different approach? Here's the test I tried that fails on the 2nd assertEquals call.

import com.netflix.hystrix.HystrixCommand;
import com.netflix.hystrix.HystrixCommandGroupKey;
import com.netflix.hystrix.HystrixCommandProperties;
import org.junit.Test;
import static org.junit.Assert.assertEquals;

public class ForceCircuitBreakerCommandTest {

    @Test
    public void testForceOpen(){

        assertEquals(Boolean.TRUE, new FakeCommand().execute());

        new OpenCircuitBreakerCommand().execute();

        assertEquals(Boolean.FALSE, new FakeCommand().execute());

    }

    private class FakeCommand extends HystrixCommand<Boolean> {

        public FakeCommand(){
            super(Setter.withGroupKey(HystrixCommandGroupKey.Factory.asKey("TestGroup")));
        }

        @Override
        public Boolean run(){return Boolean.TRUE;}

        @Override
        public Boolean getFallback() {return Boolean.FALSE;}
    }

    private class OpenCircuitBreakerCommand extends HystrixCommand<Boolean> {

        public OpenCircuitBreakerCommand(){
            super(Setter.withGroupKey(HystrixCommandGroupKey.Factory.asKey("TestGroup"))
                    .andCommandPropertiesDefaults(HystrixCommandProperties.Setter()
                                    .withCircuitBreakerForceOpen(true)));
        }

        @Override
        public Boolean run(){return Boolean.TRUE;}

        @Override
        public Boolean getFallback() {return Boolean.FALSE;}
    }
}

Solution

  • I have set custom properties such as "hystrix.command.HystrixCommandKey.circuitBreaker.forceOpen" using

    import com.netflix.config.ConfigurationManager;
    
    ConfigurationManager.getConfigInstance()
        .setProperty("hystrix.command.HystrixCommandKey.circuitBreaker.forceOpen",
        true);
    

    ConfigurationManager is the Archaius instance that is used internally.