比如报错:
(node:50751) UnhandledPromiseRejectionWarning: Unhandled promise rejection (rejection id: 2): TypeError: Cannot read property '_id' of undefined
(node:50751) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.
完全不知道哪里出了问题。
我最后发现,要大量使用 try catch,。暂时无更好的方法