README.md

Timed Diagnostic Alert

This project demonstrates the use of timed dagnostic alerts, using a circuit breaker from failsafe. The alertCondition is set up such that a call to logger.error records a failure in the circuit breaker, and after enough failures, the circuit "opens" for five seconds, causing logger.debug calls to pass the levelCondition. When there is no more remaining duration, the circuit closes again and goes back to the default logging level.

public class Main {

  private static final DiagnosticAlertManager alerts = new DiagnosticAlertManager(CircuitBreaker.builder()
          .withFailureThreshold(1)
          .withDelay(Duration.ofSeconds(5))
          .build(), Level.INFO, Level.TRACE);

  private static final Logger<?> logger = LoggerFactory.getLogger()
          .withCondition(alerts.levelCondition())
          .withCondition(alerts.alertCondition());

  public static void main(String[] args) throws InterruptedException {
    while (true) {
      try {
        logger.info("logging at INFO");   // enabled by the default threshold level
        logger.debug("logging at DEBUG"); // enabled when on diagnostic alert
        logger.trace("logging at TRACE"); // can never be enabled, logback.xml takes priority
        LocalTime now = LocalTime.now();
        int second = now.getSecond();
        if (second == 0 || second == 15 || second == 30 || second == 45) {
          throw new IllegalStateException("Oh no");
        }
      } catch (Exception e) {
        logger.error("Exception happened!", e);
      } finally {
        Thread.sleep(1000L);
      }
    }
  }
}