Discord bot UnhandledPromiseRejectionWarning in production ( HEROKU)-CodePudding

I deployed my discord bot to Heroku but It is giving an error of unhandled promise rejection Here are the logs

2021-09-10T20:50:26.000000 00:00 app[api]: Build started by user codertanishq@gmail.com
2021-09-10T20:50:45.558185 00:00 app[api]: Deploy c608c194 by user codertanishq@gmail.com
2021-09-10T20:50:45.558185 00:00 app[api]: Release v11 created by user codertanishq@gmail.com
2021-09-10T20:50:46.000000 00:00 app[api]: Build succeeded
2021-09-10T20:50:46.978335 00:00 heroku[web.1]: State changed from crashed to starting
2021-09-10T20:50:48.877754 00:00 heroku[web.1]: Starting process with command `npm start`
2021-09-10T20:50:51.529490 00:00 app[web.1]: 
2021-09-10T20:50:51.529505 00:00 app[web.1]: > start@1.0.0 start /app
2021-09-10T20:50:51.529506 00:00 app[web.1]: > node ./src/bot.js
2021-09-10T20:50:51.529506 00:00 app[web.1]: 
2021-09-10T20:50:51.762757 00:00 app[web.1]: (node:22) UnhandledPromiseRejectionWarning: ReferenceError: AbortController is not defined
2021-09-10T20:50:51.762758 00:00 app[web.1]:     at RequestHandler.execute (/app/node_modules/discord.js/src/rest/RequestHandler.js:172:15)
2021-09-10T20:50:51.762758 00:00 app[web.1]:     at RequestHandler.execute (/app/node_modules/discord.js/src/rest/RequestHandler.js:176:19)
2021-09-10T20:50:51.762758 00:00 app[web.1]:     at RequestHandler.push (/app/node_modules/discord.js/src/rest/RequestHandler.js:50:25)
2021-09-10T20:50:51.762759 00:00 app[web.1]:     at async WebSocketManager.connect (/app/node_modules/discord.js/src/client/websocket/WebSocketManager.js:128:9)
2021-09-10T20:50:51.762759 00:00 app[web.1]:     at async Client.login (/app/node_modules/discord.js/src/client/Client.js:245:7)
2021-09-10T20:50:51.762759 00:00 app[web.1]: (Use `node --trace-warnings ...` to show where the warning was created)
2021-09-10T20:50:51.763064 00:00 app[web.1]: (node:22) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). To terminate the node process on unhandled promise rejection, use the CLI flag `--unhandled-rejections=strict` (see https://nodejs.org/api/cli.html#cli_unhandled_rejections_mode). (rejection id: 2)
2021-09-10T20:50:51.763091 00:00 app[web.1]: (node:22) [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.
2021-09-10T20:50:51.847328 00:00 heroku[web.1]: Process exited with status 0
2021-09-10T20:50:51.902780 00:00 heroku[web.1]: State changed from starting to crashed

CodePudding user response：

You would have to upgrade your node version. You may add the following to your package.json:

"engines": {
    "node": "16.9.1",
  }

And redeploy your project and it would work

CodePudding user response：

Discord.js v13 needs AbortController to function, but it was only introduced in node versions 16 and above. You have two options to fix this error:

Upgrade your node version on heroku to 16 or above
Use a polyfill for your AbortController , AbortController-polyfill is a package to do that, you may utilise it like so:

const { AbortController } = require('abortcontroller-polyfill/dist/cjs-ponyfill');
global.AbortController = AbortController;