Discord bot for YouTube notifications throwing unhandled promise rejection

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1

I’m having trouble with my Discord bot that’s supposed to send YouTube notifications. It keeps throwing an UnhandledPromiseRejection error. Here’s what the error looks like:

UnhandledPromiseRejection: 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(). The promise rejected with the reason "#<Object>".

I got the code from GitHub but it’s not working as expected. It’s meant to check for new videos from a list of YouTube channels and post updates in a Discord channel.

Here’s a simplified version of what I’m trying to do:

const Discord = require('discord.js');
const YouTubeAPI = require('youtube-api-wrapper');

const bot = new Discord.Client();
const youtube = new YouTubeAPI(API_KEY);

async function checkNewVideos() {
  const channels = ['channel1', 'channel2', 'channel3'];
  
  for (const channelId of channels) {
    try {
      const latestVideo = await youtube.getLatestVideo(channelId);
      if (isNewVideo(latestVideo)) {
        sendDiscordNotification(latestVideo);
      }
    } catch (error) {
      console.error(`Error checking ${channelId}:`, error);
    }
  }
}

bot.on('ready', () => {
  console.log('Bot is ready');
  setInterval(checkNewVideos, 60000);
});

bot.login(BOT_TOKEN);

Any ideas on how to fix this error or improve the code?

2

The UnhandledPromiseRejection error typically occurs when an asynchronous operation fails without proper error handling. To address this, I’d recommend implementing a more robust error handling strategy throughout your code.

Consider adding a global unhandled rejection handler:

process.on('unhandledRejection', (reason, promise) => {
  console.error('Unhandled Rejection at:', promise, 'reason:', reason);
});

Also, ensure all async functions, including your main bot functionality, are properly wrapped in try-catch blocks. You might want to implement a custom error logging system to capture and analyze these errors more effectively.

Lastly, double-check your API key and bot token to ensure they’re valid and have the necessary permissions. Invalid credentials can often lead to unhandled rejections in API interactions.

3

hey, i had similar issue. try wrapping your bot.login and main function in try-catch so you catch async errors. hope that helps.

4

I’ve dealt with similar issues in my Discord bots. One thing that helped me was implementing a more robust error handling system. Instead of just logging errors, I started using a custom error handler that not only logs the error but also attempts to gracefully recover or restart the bot if needed.

Here’s a snippet of what worked for me:

function handleError(error, context) {
  console.error(`Error in ${context}:`, error);
  // Log to a file or external service
  // Attempt to recover or restart the bot
}

async function checkNewVideos() {
  try {
    // Your existing code here
  } catch (error) {
    handleError(error, 'checkNewVideos');
  }
}

bot.on('error', error => handleError(error, 'Discord client'));

// Wrap the entire bot initialization
try {
  bot.login(BOT_TOKEN);
} catch (error) {
  handleError(error, 'Bot login');
}

This approach has made my bots much more stable and easier to debug. It might be worth giving it a shot in your case too.