Closed
Description
Hi.
Recently, I need to know is circuit breaker is half-opened? can I execute command?
@Test
public void can_read_state_of_HALF_OPEN() {
String commandKey = "test444";
executeBeforeCircuiteOpenLimit(commandKey); //
{
waitHealthUpdate();
CommandHelloWorld cmd = new CommandHelloWorld(commandKey, true); <- when second arg is true, throw execption
assertFalse(cmd.isCircuitBreakerOpen());
try {
// over 50% error!!
cmd.execute();
fail("Must throw exception");
} catch (HystrixRuntimeException ex) {
// ok, circuit is opened!
}
waitHealthUpdate();
assertTrue("Error ratio is over 50%, circuit must be opened", cmd.isCircuitBreakerOpen());
{
CommandHelloWorld cmdAllowRequest = new CommandHelloWorld(commandKey, true);
assertFalse("When circuit is opened, not allow request", cmdAllowRequest.allowRequest());
}
}
{
waitSleepTime();
waitHealthUpdate();
CommandHelloWorld cmd = new CommandHelloWorld(commandKey, false);
assertTrue("Over sleep time, but no request tried, no status change. So circuit status is opened, too", cmd.isCircuitBreakerOpen());
/* CHECK ALLOW */ assertTrue("But over sleep time, circuit is half opened, must allow request ", cmd.allowRequest());
}
{
CommandHelloWorld cmd = new CommandHelloWorld(commandKey, false); <- when second arg is false, not throw execption, success
/* HERE */ cmd.execute();
assertFalse("over sleep, first request is succcees, circut status must be changed", cmd.isCircuitBreakerOpen());
}
{
CommandHelloWorld cmd = new CommandHelloWorld(commandKey, false);
cmd.execute();
}
}
class CommandHelloWorld extends HystrixCommand<String> {
...
public boolean allowRequest() {
return circuitBreaker.allowRequest();
}
...
@Override
protected String run() {
if (error) {
throw new IllegalArgumentException("No");
}
return "Hello " + name + "!";
}
}
But this test is failed at /* HERE */ .
Result: Circuit is shorted
So I remove /* CHECK ALLOW */ line (remove call allowRequest ),
Test is success.
I trace into circuitBreaker.allowRequest(),
And found HystrixCircuitBreakerImpl allowSingleTest method
public boolean allowSingleTest() {
long timeCircuitOpenedOrWasLastTested = circuitOpenedOrLastTestedTime.get();
// 1) if the circuit is open
// 2) and it's been longer than 'sleepWindow' since we opened the circuit
if (circuitOpen.get() && System.currentTimeMillis() > timeCircuitOpenedOrWasLastTested + properties.circuitBreakerSleepWindowInMilliseconds().get()) {
// We push the 'circuitOpenedTime' ahead by 'sleepWindow' since we have allowed one request to try.
// If it succeeds the circuit will be closed, otherwise another singleTest will be allowed at the end of the 'sleepWindow'.
if (circuitOpenedOrLastTestedTime.compareAndSet(timeCircuitOpenedOrWasLastTested, System.currentTimeMillis())) {
// if this returns true that means we set the time so we'll return true to allow the singleTest
// if it returned false it means another thread raced us and allowed the singleTest before we did
return true;
}
}
return false;
}
At Seconds If statement, It change circuitOpenedOrLastTestedTime.
I think this is bug. I just call query method, but it change status.