Function probeHealthCheck

pkg/healthcheck/executor.go:67–123

probeHealthCheck executes the health check command inside the container context

(ctx context.Context, task containerd.Task, hc *Healthcheck, processSpec *specs.Process)

// probeHealthCheck executes the health check command inside the container context
func probeHealthCheck(ctx context.Context, task containerd.Task, hc *Healthcheck, processSpec *specs.Process) (*HealthcheckResult, error) {
	execID := "health-check-" + idgen.TruncateID(idgen.GenerateID())
	outputBuf := NewResizableBuffer(MaxOutputLen)

	process, err := task.Exec(ctx, execID, processSpec, cio.NewCreator(
		cio.WithStreams(nil, outputBuf, outputBuf),
	))
	if err != nil {
		log.G(ctx).Debugf("failed to exec health check: %v", err)
		return nil, fmt.Errorf("exec error: %w", err)
	}
	defer func() {
		if _, err := process.Delete(ctx); err != nil {
			log.G(ctx).WithError(err).Debug("failed to delete exec process")
		}
	}()

	if err := process.Start(ctx); err != nil {
		log.G(ctx).Debugf("failed to start health check: %v", err)
		return nil, fmt.Errorf("start error: %w", err)
	}

	exitStatusC, err := process.Wait(ctx)
	if err != nil {
		return nil, fmt.Errorf("failed to wait for health check: %w", err)
	}

	select {
	case <-time.After(hc.Timeout):
		_ = process.Kill(ctx, syscall.SIGKILL)
		<-exitStatusC
		process.IO().Wait()
		process.IO().Close()
		msg := fmt.Sprintf("Health check exceeded timeout (%v)", hc.Timeout)
		if out := outputBuf.String(); len(out) > 0 {
			msg = fmt.Sprintf("Health check exceeded timeout (%v): %s", hc.Timeout, out)
		}

		log.G(ctx).Debugf("health check timed out: %s", msg)

		return &HealthcheckResult{
			ExitCode: -1,
			Output:   msg,
			End:      time.Now(),
		}, nil

	case exitStatus := <-exitStatusC:
		process.IO().Wait()
		process.IO().Close()
		code, _, _ := exitStatus.Result()
		return &HealthcheckResult{
			ExitCode: int(code),
			Output:   outputBuf.String(),
			End:      time.Now(),
		}, nil
	}
}