我正在使用IBM Bluemix IOT Foundation中提供的Node-red。它附带了node-red-node-cf-cloudant软件包，可以轻松处理Cloudant数据库操作。 Cloudant out节点运行良好。我的边界是 Cloudant out节点没有输出，如果插入/更新操作成功，它可以告诉流程。现在我只能假设它总是成功的。有人和我一样有问题吗？你的解决方案是什么？感谢。
答案 0 :(得分：0)
我认为，哲学是有一个Catch节点的概念可以添加到流中。有关标记为input的节点，请参阅catch类别。阅读此节点的文档，它指出如果同一选项卡/页面/工作流上的任何节点抛出错误，它将被触发。我假设如果Cloudant out节点正确实现，那么如果它失败，它将抛出一些Node-RED格式的错误，导致Catch节点被触发，这样你就可以获得控制来执行任何错误处理，记录或其他可能适用的补救工作。
我猜测跟踪创建的Node-RED Github问题以及可以在其中阅读更多关于该功能的问题可以在这里找到：
答案 1 :(得分：0)
我有一个答案，虽然它不是一个非常有用的答案。
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检查此代码。我可以使用catch节点捕获从Cloudant输出节点抛出的任何错误，并将其设置为流上下文对象。因此，原始路径可以在短暂延迟之后检查上下文中是否存在错误对象。如果在上下文中找不到错误，则假定更新成功。
但是，这不是一个有用的解决方案。在同一个Node-red实例中收到多个请求时，会出现并发问题。并且错误对象中没有会话标识符。我无法将错误消息与导致错误的消息相关联。希望有人能找到改进此解决方案的方法。