[PYTHON] Let's execute the command on time with the bot of discord

The point

• Develop in python using discord.py.
• Implement a background loop with discord.ext.tasks. Code
• Use croniter to determine whether or not a job needs to be fired in each loop (timing). Code
• Command.invoke () enables bots to execute bot commands To do. Code

What is discord.py?

Discord has Bot Development Library for Many Languages and a library for python [discord.py](https:: //pypi.org/project/discord.py/).

I tried it

Use discord.py to create a bot that can be used when recruiting online game quests and matchmaking opponents, and actually use it for about a month. I've seen it, so I'll write it as an article.

Outline specifications

Set of code

Click here for the code rather than the theory. https://github.com/coleyon/discord-partypoll

What kind of function?

Roughly speaking, it is a bot that consists of the following two functions.

• PartyPoll-Similar to SimplePoll, a function that allows you to publicize the event and recruit participants.
• Cron --PartyPoll command to the bot itself, cron Scheduling and scheduled execution with a similar setting format Function to make

What kind of environment is it?

Bot as a Python program is configured to run on a Docker container.

Environment

Prepare the server and OS

For example, set up ʻUbuntu 18.04 LTS x86-64` on EC2. The free tier is sufficient.

Install Docker server environment

Install docker and compose.

• https://docs.docker.com/engine/install/ubuntu/
• https://docs.docker.com/compose/install/

Install Docker server environment

I think it looks like this.

$ docker --version
Docker version 19.03.12, build 48a66213fe
$ docker-compose --version
docker-compose version 1.27.2, build 18f557f9
$ id
uid=1000(ubuntu) gid=1000(ubuntu),
#Omission...
,999(docker)
$ 

Build a Docker container

$ git clone  https://github.com/coleyon/discord-partypoll.git
Cloning into 'discord-partypoll'...
...
Resolving deltas: 100% (136/136), done.
$ cd discord-partypoll/
$ docker-compose build
$ docker images | grep partypoll
discord-partypoll_discord-bot  latest ...
$ 

Invite the bot to the Discord server

Make a Discord app

Create an application on the Developer Portal (https://discord.com/developers/applications).

Set the bot's OAuth2 Token in the bot program

Get the Client Secret from the app's General Information menu and set it to DISCORD_BOT_TOKEN in docker-compose.yml.

version: "3"
services:
  discord-bot:
    restart: always
    build: .
    environment: 
      DISCORD_BOT_TOKEN: "yourtoken"

Invite the bot to the Discord server

Get the OAuth2 URL where Scopes is BOT from the ʻOAuth2menu of the app. For Permissions, giveSend Messages, Manage Messages, ʻAttach Files, Mention Everyone, ʻAdd Reactions`.

Invite the bot to the Discord server

Access the OAuth2 URL in your browser and invite the bot to the Discord server.

Launch the bot program

Generate dependent libraries for Bot programs

Generate requirements.yml from Pipfile.

$ pipenv lock -r > requirements.txt

Launch the bot program

Start the Bot program (Docker container as the execution environment).

$ docker-compose up -d
$ docker-compose logs -f
Attaching to discord-partypoll_discord-bot_1
discord-bot_1  | -----Logged in info-----
discord-bot_1  | {BOT_NAME}
discord-bot_1  | {BOT_ID}
discord-bot_1  | {DISCORDPY_VERSION}
discord-bot_1  | ------------------------
discord-bot_1  | Poll Extension Enabled.
discord-bot_1  | Cron Extension Enabled.
^CERROR: Aborting.
$ 

Launching the Bot program brings the bot on Discord online and ready for use.

Try using the party recruitment command ppoll

Recruitment that can limit the total number of recruitment

This command is for recruiting parties with a maximum of 20 people in total for the entire team. / ppoll total 20 people 3 teams 20 TeamA TeamB TeamC

Recruitment that can limit the number of people for each recruitment item

This command is for recruiting parties for up to 4 people in total for each team. / ppoll each 4 people 3 teams [4] TeamA [4] TeamB [4] TeamC

Help command

See the / ppoll help command description or the Git repository readme.md for more information.

Try using the scheduled execution command cron

Execution time zone specification

You can set the execution timezone. The default is Japan time (Asia / Tokyo), but you can set it to something like Eastern Time (EST).

Job definition and activation

• Define a Job.
• `/ cron add" Job A "* / 1 * * * mon-fri / ppoll each 4 people 3 team party ({{1.days}} held!) [4] TeamA [4] TeamB [4] TeamC ``
• Bring cron up and running (assuming you ran it at 23:11 on October 30, 2020)
• /cron enable

Job operation example

It will be like this. See the / cron help command description or the Git repository readme.md for more information.

Reference material

Basically, Official Docs is the bible, but the members of the online game introduced the following books during the making.

When I read it, it was very easy to understand and it was useful because there were many contents that I could not grasp in the official manual, so it is recommended for those who are interested in making Discord bots.

• Introduction to Discord Bot development practice made with Python
• https://techbookfest.org/product/5755158612934656?productVariantID=5633838124367872