how to remove unhandledPromiseRejectionWarning?

[Lancernix]

When I was testing whether the select function I wrote was correct, I deliberately wrote a wrong column name. Then the console output the corresponding error, but there was an unhandledpromiserejectionwarning. I added try...catch to all async functions, but warning still existed. It seems to be promise.js in mysql2 omits the handle of promise rejection? Or just there are something incorrect with my code? This warning does not affect the operation of the function, but how can I successfully remove the unhandledpromiserejectionwarning?

code:

console:

[flipperlite]

Why would you want to remove it? It's an error that needs to be handled gracefully for the user. In your two functions, you have in your catch block throw error; which is correct IMHO. That means you're bubbling up the error and need to ultimately catch it at a higher level. If it goes unhandled, it may crash your app. For example if you were using NodeJS Express, you'd have a higher level try/catch block in your middleware function that would do a return next(error);. You could then have Express handle the error or use your own middleware function to scrub the raw error and display a user friendly error like "Oops. Something went wrong." so you're not sending out sensitive information. BTW, the try/catch block in your two functions are not necessary since you're not doing anything with the error object and you could remove the try/catch blocks assuming you catch the error upstream.

Here's a link on how to handle errors in NodeJS Express. If you're using another backend stack, the concepts are similar.

[sidorares]

@Lancernix I agree with @flipperlite comment - it's likely a sign of a problem in your code and need to be addressed as such ( adding an error handler, fixing actual error etc ). Closing the issue for now but feel free to post follow up questions here