README.md

Circuit Breaker with Camel

 +--------------------+           +---------------------+ 
 |                    |           |                     | 
 |  REST Service      |<+-------+-+   Client Service    | 
 |                    |           |                     | 
 +--------------------+           +---------------------+ 

How to

Simple case (no circuit breaker)

Run application

mvn spring-boot:run

Timeout case (no circuit breaker)

Set timeout 3 sec in RestService.java

    public static void waitDelay(Exchange exchange) throws InterruptedException {
        Thread.sleep(3000);
    }

Run application

mvn spring-boot:run

Timeout case (with circuit breaker)

Keep timeout 3 sec in RestService.java

public static void waitDelay(Exchange exchange) throws InterruptedException {
    Thread.sleep(3000);
}

Uncomment Hystrix configuration in ClientService.java

from("timer:demo?period=1s").routeId("consumer")
        .hystrix()
        .hystrixConfiguration()
        .executionTimeoutInMilliseconds(1000)  an execution timeout for actions inside the hystrix block
        .circuitBreakerRequestVolumeThreshold(2) the circuit breaker request volume threshold. This is the minimum number of requests that must be received a minimum before the circuit can be opened due to failures
        .metricsRollingPercentileWindowInMilliseconds(60000)   the duration of percentile rolling window in milliseconds. This is period of time that is analyzed to determine if the circuit should be opened due to failures.
        .circuitBreakerSleepWindowInMilliseconds(15000)  the time in milliseconds after the circuit breaker trips open that it should wait before trying requests again
        .circuitBreakerErrorThresholdPercentage(50)  the error percentage threshold (as whole number such as 50) at which point the circuit breaker will trip open and reject requests
        .end()
        .to("http4:localhost:8080/api/products?socketTimeout=1000")
        .onFallback().process(this::fallback)
        .endHystrix()
        .log("${body}");

Run application

mvn spring-boot:run