如果最后一个操作以异常方式完成,则Kotlin协程将立即给出异常

当我试图通过改型登录我的服务时。当我的服务关闭时,单击按钮10秒后,我得到一个 SocketTimeoutException 例外。 到目前为止一切正常,但再次,我点击了按钮后,错误立即给出了相同的错误。发生了什么?

interface LoginService {

    @FormUrlEncoded
    @POST("/login")
    fun login(@Field("id") id: String, @Field("pw") pw: String): Deferred<Response<User>>

}

class LoginViewModel : ViewModel() {

    private var job: Job = Job()
    private val scope: CoroutineScope = CoroutineScope(Dispatchers.Main + job)
    private val service by lazy { RetrofitApiFactory().create(LoginService::class.java) }
    private val excHandler = CoroutineExceptionHandler { _, throwable ->
        Timber.e(throwable);
    }

    fun doLogin(id: String, pw: String) {
        scope.launch(excHandler) {
            val response = service.login(id, pw).await()
            if (response.isSuccessful) {
                response.body()
                        ?.let { user -> doOnSuccess(user) }
                        ?: doOnError(InvalidUserException())
            } else doOnError(Exception())
        }
    }

    private fun CoroutineScope.doOnError(e: Throwable) {
        excHandler.handleException(coroutineContext, e)
    }

    private fun doOnSuccess(user: User) {
        ...
    }

    override fun onCleared() {
        job.cancel()
    }

}