func()

in ecs-init/engine/engine.go [227:274]

• 44 lines of code
• 10 McCabe index (conditional complexity)

func (e *Engine) StartSupervised() error {
	docker, err := getDockerClient()
	if err != nil {
		return dockerError(err)
	}
	agentExitCode := -1
	retryBackoff := backoff.NewBackoff(serviceStartMinRetryTime, serviceStartMaxRetryTime,
		serviceStartRetryJitter, serviceStartRetryMultiplier, serviceStartMaxRetries)
	for {
		err := docker.RemoveExistingAgentContainer()
		if err != nil {
			return engineError("could not remove existing Agent container", err)
		}

		log.Info("Starting Amazon Elastic Container Service Agent")
		agentExitCode, err = docker.StartAgent()
		if err != nil {
			return engineError("could not start Agent", err)
		}
		log.Infof("Agent exited with code %d", agentExitCode)

		switch agentExitCode {
		case upgradeAgentExitCode:
			err = e.upgradeAgent(docker)
			if err != nil {
				log.Error("could not upgrade agent", err)
			} else {
				// continuing here because a successful upgrade doesn't need to backoff retries
				continue
			}
		case containerFailureAgentExitCode:
			// capture the tail of the failed agent container
			log.Infof("Captured the last %s lines of the agent container logs====>\n", failedContainerLogWindowSize)
			log.Info(docker.GetContainerLogTail(failedContainerLogWindowSize))
			log.Infof("<====end %s lines of the failed agent container logs\n", failedContainerLogWindowSize)
		case TerminalFailureAgentExitCode:
			return &TerminalError{
				err:      "agent exited with terminal exit code",
				exitCode: TerminalFailureAgentExitCode,
			}
		case terminalSuccessAgentExitCode:
			return nil
		}
		d := retryBackoff.Duration()
		log.Warnf("ECS Agent failed to start, retrying in %s", d)
		time.Sleep(d)
	}
}