Method countFailure

modules/caddyhttp/reverseproxy/healthchecks.go:587–640

countFailure is used with passive health checks. It remembers 1 failure for upstream for the configured duration. If passive health checks are disabled or failure expiry is 0, this is a no-op.

(upstream *Upstream)

// duration. If passive health checks are disabled or
// failure expiry is 0, this is a no-op.
func (h *Handler) countFailure(upstream *Upstream) {
	// only count failures if passive health checking is enabled
	// and if failures are configured have a non-zero expiry
	if h.HealthChecks == nil || h.HealthChecks.Passive == nil {
		return
	}
	failDuration := time.Duration(h.HealthChecks.Passive.FailDuration)
	if failDuration == 0 {
		return
	}

	// count failure immediately
	err := upstream.Host.countFail(1)
	if err != nil {
		if c := h.HealthChecks.Active.logger.Check(zapcore.ErrorLevel, "could not count failure"); c != nil {
			c.Write(
				zap.String("host", upstream.Dial),
				zap.Error(err),
			)
		}
		return
	}

	// forget it later
	go func(host *Host, failDuration time.Duration) {
		defer func() {
			if err := recover(); err != nil {
				if c := h.HealthChecks.Active.logger.Check(zapcore.ErrorLevel, "passive health check failure forgetter panicked"); c != nil {
					c.Write(
						zap.Any("error", err),
						zap.ByteString("stack", debug.Stack()),
					)
				}
			}
		}()
		timer := time.NewTimer(failDuration)
		select {
		case <-h.ctx.Done():
			if !timer.Stop() {
				<-timer.C
			}
		case <-timer.C:
		}
		err := host.countFail(-1)
		if err != nil {
			if c := h.HealthChecks.Active.logger.Check(zapcore.ErrorLevel, "could not forget failure"); c != nil {
				c.Write(
					zap.String("host", upstream.Dial),
					zap.Error(err),
				)
			}
		}
	}(upstream.Host, failDuration)
}