如何修复反应功能不起作用（机器人重新启动后）

Question

So I am working on a discord.js ticket system and I ran through a bug which I can't seem to fix by myself.

Basically, I work with reactions to open & close tickets, but if someone makes a ticket and then I restart the bot, the ticket created before the restart doesn't work. The reaction that should close the ticket, doesn't - but it does work on any tickets made after the reset

My code:

    else if(reaction.emoji.name === '🔒') {

        if(userTickets.has(user.id)) {
            if(reaction.message.channel.id === userTickets.get(user.id)) {
                reaction.remove(user);
                let embed = new RichEmbed();
                embed.setDescription("Ticket will be closed in 5 seconds.")
                reaction.message.channel.send(embed);
                setTimeout(() => {
                    reaction.message.channel.delete('closing ticket')
                    .then(channel => {
                        console.log("Deleted " + channel.name);
                    })
                    .catch(err => console.log(err));
                }, 5000);
            }
        }

        else if(reaction.message.guild.channels.some(channel => channel.name.toLowerCase() === user.username + 's-ticket')) {
            let embed = new RichEmbed();
            embed.setDescription("Ticket will be closed in 5 seconds.");
            reaction.message.channel.send(embed);
            setTimeout(() => {
                reaction.message.guild.channels.forEach(channel => {
                    if(channel.name.toLowerCase() === user.username + 's-ticket') {
                        channel.delete().then(ch => console.log('Deleted Channel ' + ch.id))
                    }
                });
            }, 5000);
        }
    }
});

Answer 1

You must handle events for uncached messages

The reason it doesn't work on reload is because the cache is cleared every time you restart the bot. Only new messages will be cached. Reaction events aren't triggered on unloaded messages.

To solve this problem, you will have to listen for raw events. It looks like this:

// check for reactions on unloaded messages and trigger the appropriate events
client.on('raw', packet => {
  if (!['MESSAGE_REACTION_ADD', 'MESSAGE_REACTION_REMOVE'].includes(packet.t)) return;
  const channel = client.channels.get(packet.d.channel_id);
  if (channel.messages.has(packet.d.message_id)) return;
  channel.fetchMessage(packet.d.message_id).then(message => {
    const emoji = packet.d.emoji.id ? `${packet.d.emoji.name}:${packet.d.emoji.id}` : packet.d.emoji.name;
    const reaction = message.reactions.get(emoji);
    if (packet.t === 'MESSAGE_REACTION_ADD') { client.emit('messageReactionAdd', reaction, client.users.get(packet.d.user_id)); }
    if (packet.t === 'MESSAGE_REACTION_REMOVE') { client.emit('messageReactionRemove', reaction, client.users.get(packet.d.user_id)); }
  });
});

I can't explain it better than how Évelyne Lachance does in the original guide i took this from , so if you want to understand how this works, read it there.

This snippet will automatically call the messageReactionAdd and messageReactionRemove events and pass on the necessary arguments, so you won't really need to do much apart from copy-pasting this in your main file.