tterrag1098/k9

A Discord bot with some useful commands.

K9

A Discord bot with some useful commands.

It uses Discord4J, an awesome Java library for the Discord API.

About

K9 was originally created for a server about Minecraft modding, and its first command was to look up MCP mappings. It still has this feature, but there is now much more!

• Custom pings for arbitrary regex (!ping)
  • Ever wanted to be pinged for something other than your username? Want to make sure to catch every time someone says your name, because you're a creepy bastard with nothing better to do? Then this is the command for you!
• A command to manage "information" channels
  • Allows any administrator to update the content of an information channel from an outside source.
• A Clojure REPL emulator (!clj)
  • If you know what this means, then you're probably a nerd.
• The ability to create custom commands (called "tricks") which can process user input and execute code (!trick)
  • I don't have a funny quip for this one, but trust me, it's neat!
• Look up CurseForge projects and download counts for any username (!cf)
  • You're so vain, I bet you'll run this command on yourself.
• Lets you keep track of the best quotes from your server, and even battle them together head-to-head! (!quote)
  • Because everything is funnier out of context.
• The ability to change the command prefix
  • What do you mean other bots already use an exclamation mark?
• Create drama (!drama)
• Slap people (!slap)
• More to come!

It also features a complete help system, so figuring out how to use a command is as simple as !help [command].

How do I get K9 in my server already?

Well, if you're lucky enough to know me, just ask. Currently the instance of K9 I run is private, so only I can invite it to servers I personally know the owners of. However, K9 is open source and the build server I use is public, so it's easy to set up your own instance! See the next section for a how-to.

So you want to run your own K9

Great! Before doing anything, make sure you have the latest version of Java 8 installed on the machine that will be running the bot.

1. Download the bot from Jenkins. Make sure to grab the -all jar, it includes all the libraries needed to run K9 inside it.
2. Create a Discord App. Give it an appropriate name, and make sure to click the "Create a Bot User" button. After that, make sure to copy the bot token, you'll need it for the next step!
3. That's all the setup! Make sure the bot jar is inside a clean directory (it will create some folders for storing data), and then you can run it with the syntax: java -jar [jar name] -a [bot token]. You might want to do this inside a screen or similar.

And that's all! You should see a lot of console output, and then the bot will be running! To invite it to a server, use the "Generate OAuth2 URL" button on the app page. What permissions you give the bot is up to you, but it does not (currently) need any more than these:

I know this sounds impossible, but I think K9 can be better. How can I help?

See the CONTRIBUTING.md file.

k9's Issues

When listing mappings, K9 does not list overloaded functions.

TO REPRODUCE:
Use the command !moj bon.a, and notice how there is only one of method instead of the multiple that are there

The help command doesn't take the server's command prefix into account

See here:

tricks not showing thrown exceptions

creating a trick like:
!trick -at clj trickname (throw (Exception. "Hi"))
will output:
Error evaluating trick: null
whereas
!clj (throw (Exception. "Hi"))
will output the expected
Could not process command: java.security.PrivilegedActionException: java.lang.Exception: Hi

Please put exact matches first when listing mappings

Doing !yc Feature puts the class whose name is exactly Feature on the 10th page...

trick parameters starting with a numeric character that are not numbers error

Input: ?trick echo 4D
Expected output: ("4D")
actual output: Error evaluating trick: Invalid number: 4D

Add high five feature from the Chisel IMC server

I miss the old feature from the chisel IMC where if two people typed o/ or \o in a row, the bot would mention the high five and increment their counter. Would be a nice feature to include in K9

Prevent info channel command from pinging users/roles

Currently, from my reading of the code and anecdotal evidence from cpw's last updating of the #rules channel on Forgecord, whenever a channel is updated using K9's info command, it pings any users or roles within the message text (excluding embeds, because pings do not work in embeds).

This presents a difficulty whenever a server owner or administrator is updating such channels using the info command and the text contains mentions of roles or users (such as listing the staff roles of the server), because any update will cause a ping to be sent to all users, which means that server owners/administrators have to coordinate with these pinged users to make sure they know that this ping is due to an update of the rules channel (to avoid inciting irritation or anger from those users who hate pings with a passion unrivaled).

However, I have found a solution residing in the Discord Developer documentation for Channels, for the Allowed Mentions Object.
The Allowed Mentions object in messages allows granular control whether what mentions in a message will actually cause a ping to be sent to users. It allows controlling mentions for: roles, users, @everyone/@here, specific roles, and specific users.
As a side effect, it also disables the yellow background in messages with pings.

Image of my bot using the Allowed Mentions feature to prevent a ping to myself

Image of my bot using the Allowed Mentions feature to prevent a ping to another user, with their confirmation

The yellow background of the bot's message is due to it being a reply message (with mention) to my own command.

Discord4J implements this through MessageCreateSpec#setAllowedMentions(AllowedMentions), taking in an AllowedMentions object, built using its own Builder class which defaults to (to my understanding) an empty AllowedMentions object which prevents all mentions from becoming pings.
As a reference, JDA implements this feature through MessageAction#allowedMentions(Collection<Message.MentionType>) and other related methods when sending messages. To implement this in my bot, I have passed in an empty collection, and the results of that are shown above.

This feature will be very useful to servers that use K9's info command to manage rules channels, so their owners/administrators can update the rules for e.g. spelling mistakes or minor clarifications, without having to ping and disturbed those mentioned users/roles. ^{(cough Forgecord cough)}

Search results by MCP and srg name differs

Check this screenshot:
First command result does not include TileEntity class
Is this intended?

Easy quoting

Feature request: automatically quote anything reacted to with 💾 (or a custom "quote" emoji if you want to get fancy).

Exception thrown during mcpm command

Just execute !mcpm func_77659_a 1.7.10
It will throw this exception:

This happens on my instance and on sponge server instance.

Spigot mapping support

Would it be possible to add support for spigot's mappings as well? This discord bot seems very useful, but the thing is I would need to be able to use spigot's mappings as well. Is this something that could possibly be added?

No natives in -all package from jenkins

I got this error:

14:21:02 [elastic-2] i.n.u.i.NativeLibraryLoader Unable to load the library 'netty_transport_native_epoll_x86_64', trying other loading mechanism.
java.lang.UnsatisfiedLinkError: no netty_transport_native_epoll_x86_64 in java.library.path

X in quote list (and possibly ping list) vanishing

This issue exists mostly as a reminder to myself to look into this later.
While browsing the list of quotes in the Forge server, the X disappeared!

https://discord.com/channels/313125603924639766/540691915373412393/780213820110012446

I have no idea what caused it.

Security manager

Is it still needed? My old command line has it

K9 spamming ping notifications in guild chats

Message link

For some reason, K9 started sending ping notifications seemingly matching the regex /.*/ to guild channels in Fabric discord. We have no idea why or how it started doing this

All threads deadlocked immediately after starting

Another reminder to myself to look into this.
I booted it up like normal, but after listing the servers it's in..

16:01:47 [boundedElastic-6] com.tterrag.k9.K9   Guinevere Central  
16:01:47 [boundedElastic-6] com.tterrag.k9.K9   yeetum-bots  
16:01:47 [boundedElastic-6] com.tterrag.k9.K9   The Dugre project  
16:01:47 [boundedElastic-6] com.tterrag.k9.K9   Bolb Quarantine  
16:01:47 [boundedElastic-6] com.tterrag.k9.K9   Gemwire Randomness  
16:01:47 [boundedElastic-6] com.tterrag.k9.K9   Curle Army   
16:02:17 [parallel-5] c.t.k.c.a.CommandRegistrar Saving all command data.  
16:07:17 [parallel-5] c.t.k.c.a.CommandRegistrar Saving all command data.

It dropped off the user list and doesn't respond to commands.
Thread dump says that all threads are deadlocked, waiting for each other.
https://paste.gemwire.uk/view/raw/504a12ca

not handling disconnects properly

https://gist.github.com/phit/31feb41cd9d1ced92d620b5fd48ba005

Not sure whats going on, I guess discord is having issues? This is the second time I had to
kill -9 pid the process, as it wasn't responding to ctrl C or sending sigterm.

I was running build 236, updated to 240 as I saw D4J was updated, not sure if that will fix it. Figured I'll make an issue anyway if it doesn't.

[Suggestion] xkcd linking

(Idea from BobbyTablesBot on Reddit.)

Suggestion: If a user ran !xkcd 303, K9 would post the link to xkcd 303 in the chat (keeping the embed). Same if they ran !xkcd Compiling or !xkcd compiling.
No idea how hard this would be to implement, but it'd be really neat 😄

Bot admin

Currently bot has hardcoded admin id, can this be changed?

Trick prefixes mild UX annoyance

The trick prefix is mildly irritating when you forget if it's ?! or !?

Can we instead change it to a double prefix? e.g. if your commands are configured to use ! the trick shortcut is !! ?

Otherwise just being able to configure prefixes for tricks would be cool.

(Feature request) Pings pinging while actively engaged in conversation.

Pings with the !ping command ping you even while you're actively engaged in conversation. Instead, K9 should check if you've been active in the channel in the last couple of minutes and only ping if you haven't.

CommandCustomPing is vulnerable to ReDOS

There is no timeout for the regex matching here, leaving the bot vulnerable to malicious regexes that take excessive time to evaluate.

Comments at the end of tricks cause EOF errors

A trick like

;;start of trick
(+ 1 1)
;;end of trick, we have calculated 1 + 1

Will cause an EOF error despite being, as far as I know, valid clojure

[Enhancement] Tricks Info Channel

Just a quick feature idea i had today, this could be implemented in multiple ways, here's a couple:

1. Allow the creation of a channel (similar to the !info command) that contains a current list of Tricks registered with the bot and their output, have this list update whenever a trick is updated

2. Add a flag to the trick execution command to allow it to remain "updated", so whenever the command is updated the output is also updated.

3. Similar to 1, but allow for only select tricks in the channel (to avoid "prank" tricks/etc in the channel)

Allow authentication to be supplied via file path rather than on the command line

The discord token is on the command line, bare. This could be considered a security risk and is generally incompatible with things like docker secrets (without hacks).

Allow passing a file containing the secret instead, for much securityness..

Hidden strings trigger pings

https://github.com/tterrag1098/K9/blob/master/src/main/java/com/tterrag/k9/commands/CommandCustomPing.java#L81
Looks like things like emoji and channel names trigger pings. It's very annoying when someone does <:any_string_they_want:emote id> since the Discord client renders the emoji but you get the ping

[Improvement] Rewrite this bot in JDA

JDA>Discord4J
:^)

(Feature request) Allow adding cutsom info to tricks

For documentation, telling the purpose, or anything like that. Could be done with an --add-info flag or something. I dunno I haven't given it too much thought.

[enhancement] allow any message by K9 to be deleted with a reaction

I think that K9 should delete any message that it sends if reacted to with ❌.

Bot does not work

I'm self hosting this bot. Today it broke, so i restarted it, but it didn't help.
I updated it to 0.6.0-367, but it still doesn't work.
I guess it's related to mappings website shutdown, right?
How can i fix this issue?

!mcp func_151000_E
BOT K9: Unexpected error processing command: No such srg version: Unknown

Slap

Tagging @k9 in !slap does not slap the user

(Feature request) Make quotes use Discord's new markdown support for quotes.

like a quote

Question: Mojang proguard obfuscation map

Since 19w36a, Mojang has released proguard obfuscation map. The map allows for "private use" and disallows any distribution.

So two questions:

1. Is it legal for K9 to add a mojang mapping lookup feature?
2. If it is legal, will K9 have such a feature?

Cannot start bot - Disallowed intent(s)

The bot fails to start.
Version: 0.6.0-364-all
Log output: https://pastebin.com/fJU8swu6

[QUESTION] More Mappings?

K9 has got Yarn, K9 Has got MCP. When will K9 get Mojang Mappings?

[Enhancement] Trick Aliases

Pretty simple, allow for tricks to have aliases. One thing that commonly tricks me up is a trick name being plural or not. Having aliases would be useful to solve this

Preserve removed and modified messages

Listen channels for message modification and save differences in dedicated channel.

1. If someone removes message, repost it in special channel
2. If someone modifies message, send diff in special channel

Field types

Show field type in mcpf command output.
May be useful

Suggestion: add a !react command

Add a !react command that takes a message link and emoji name as a parameter, and adds the reaction to the message, then removes it after 30 seconds. During this time, the person who used the command can click the reaction and add theirs, allowing non-nitro users to react with any emoji from a server K9 is on.

Bot stopped form working

I'm running 0.6.0-358

User: !mcpm getAliases 1.12.2
K9: Unexpected error processing command: com.google.gson.JsonSyntaxException: java.lang.IllegalStateException: Expected BEGIN_OBJECT but was STRING at line 1 column 1 path $

Some embed tricks are broken

Example (In sponge discord): https://discordapp.com/channels/142425412096491520/401643018773463040/591169260684836869 (and a few messages above)

Dunno why, but the bot is reportin "incorrect number of arguments".

(Enhancement) require a "battle" on quote creation to not have so many awful quotes.

On the battle side of things I'd maybe not allow whitenames or bluenames who haven't been on the server for at least six months to vote? There are also people like Redfire who vote randomly, they should be banned from voting in battles.

Old style embeds

After bot update, i noticed that mappings response is plain text.
Is it possible to switch to embeds as it was in older versions?

Command names are ambiguous and confusing

1. None of their names actually describe what they do. The bot just assumes everyone will immediately know that !yc means !lookup_class
2. Some of them have multiple meanings (i.e. mcage can be m_cage or mc_age)
3. Running !help command doesn't do what help commands normally do (That's put under !commands for some reason, which does what !list would normally do)
4. Relating to 1: running !commands does not provide any description of what any of the commands actually do.

Suggested changes:
!commands -> help (and add descriptions as per !help [command]

(keep originals as aliases)
!yc -> !class
!ym -> !method
!yf -> !field
!yp -> !param
!clj -> !eval
!mcage -> !mc_age
!yv -> !yarn_version
!lmgtfy (imgur?) -> !google

Allow quote authors to remove their own quotes

!cf is broked

Curse redesign thingie seems to have broken the cf command

K9 0.5.0.260 (on the moddedmc server)

[Quote Battle] Keep the winning quote in chat while voting for death or save

As the title says, it would be great if we could see the winning quote in chat and the amount of votes for/against while the voting for death or spare is still active.

Perhaps where the arrow is it could say something like ... "against Quote # by x votes`. It would be nice to be able to see the quote which was deemed better than the one that lost and by how much.