Discord.py Variables Not Constant Throughout The Code

I am currently developing a bot using discord.py and in this case using a JSON file to store the bots prefixes for each server that it is in. ( + is the bots default prefix ) With

Solution 1:

Your code makes no sense to me in many places, because you use ctx in a message event, which is not possible at first. Also, when copying the code, I get an error with prefixes = prefix, so it is questionable why this supposedly works for you.

Your on_guild_join also makes no sense to me, because everyone has the default prefix. The event may be relevant for your changeprefix command, but that can be done better.

I rewrote your changeprefix command a bit and adjusted your on_message event.

Take a look at the following code:

@bot.eventasyncdefon_message(message):
    if message.content.startswith("What is the prefix for this guild?"):
        withopen('prefix.json', 'r', encoding='utf-8') as fp:
            custom_prefixes = json.load(fp)
        try:
            prefix = custom_prefixes[f"{message.guild.id}"] 
            await message.channel.send(f'Hi my prefix for this server is **{prefix}**')
        except KeyError:
            returnawait message.channel.send("You have not set a new prefix.") # No JSON entryawait bot.process_commands(message)


@bot.command()asyncdefsetprefix(ctx, prefixes: str):
    withopen('prefix.json', 'r', encoding='utf-8') as fp:
        custom_prefixes = json.load(fp)

    try:
        custom_prefixes[f"{ctx.guild.id}"] = prefixes # If the guild.id already existsexcept KeyError: # If there is no JSON entry
        new = {ctx.guild.id: prefixes} # New prefix with command input
        custom_prefixes.update(new) # Add guild.id and prefixawait ctx.send(f"Prefix set to: `{prefixes}`")

    withopen('prefix.json', 'w', encoding='utf-8') as fpp:
        json.dump(custom_prefixes, fpp, indent=2)

As your on_guild_join event also contains errors we have to determine the prefix in a different way. We can achieve that if we append the set prefix to the default one.

Have a look at the following code:

defdetermine_prefix(bot, msg):
    guild = msg.guild
    base = [DEFAULT_PREFIX]

    withopen('prefix.json', 'r', encoding='utf-8') as fp: # Open the JSON
        custom_prefixes = json.load(fp) # Load the custom prefixesif guild: # If the guild existstry:
            prefix = custom_prefixes[f"{guild.id}"] # Get the prefix
            base.append(prefix) # Append the new prefixexcept KeyError:
            passreturn base

[...](command.prefix = determine_prefix) # Where you defined your bot