iris-discord-bot/bot/main.py

import logging, os
import discord
from discord.ext import commands
import asyncpg, asyncio


# Called when the database does not seem to exist.
def sql_db_does_not_exist():
	logging.error("Database does not exist. Doublecheck if it has been created, and the user has access.")
	quit()

# Called when SQL authentication fails.
def sql_authentication_error():
	logging.error("Database authentication failed. Doublecheck username & password, and if the user has been created.")
	quit()

# Called on settings issue.
def hint_quit():  # Hint how to edit the settings and quit
	logging.info("")
	logging.info("    edit local_settings.py")
	logging.info("")
	quit()

# Called when settings file is not present.
def missing_config():  # Copy or create settings file if missing
	logging.basicConfig(level=logging.DEBUG)
	if not os.path.exists("local_settings.py"):
		logging.error("Settings file not found.")
		logging.info("Copying local_settings_example.py to local_settings.py")
		try:
			os.system("cp local_settings_example.py local_settings.py")
		except FileNotFoundError:
			logging.info("local_settings_example.py not found, creating local_settings.py")
			with open("local_settings.py", "w") as settings_file:
				settings_file.writelines(
					[
						"import logging",
						"LOG_LEVEL = logging.INFO	# Options: CRITICAL, ERROR, WARNING, INFO, and DEBUG",
						"",
						"DATABASE_NAME = \"\"",
						"DATABASE_USER = \"\"",
						"DATABASE_HOST = \"\"",
						"DATABASE_PASSWORD = \"\"",
						"",
						"WEB_HOST = \"\"",
						"WEB_SCHEME = \"\"",
						"",
						"DISCORD_TOKEN = \"\"",
						"COMMAND_PREFIX = \"\"",
					]
				)
	logging.error("Settings undefined.")
	logging.info("Configure the settings:")
	hint_quit()

# Issue with specific setting
def correct_setting(setting):  # Hint to correct specific setting and quit
	logging.info("Correct the %s in local_settings.py", setting)
	hint_quit()


# Attempt to import the local settings and quit gracefully on failure
try:
	import local_settings as settings  # Environment dependant settings stored in local_settings.py, untracked by .gitinore
except ModuleNotFoundError:  # Local settings module import failure
	missing_config()  # Prepare for configuration and inform operator

async def main():
	# Set loglevel
	try:
		logging.basicConfig(level=settings.LOG_LEVEL)
	except AttributeError:
		missing_config()

	# Define robot
	intents = discord.Intents.default()
	intents.message_content = True
	intents.invites = True
	intents.members = True

	# Try being a bot
	try:
		bot = commands.Bot(
			command_prefix="/",
			description="Charlie's Angels bot",
			intents=intents,
			case_insensitive=True,
		)
	except AttributeError:
		missing_config()

	# Extensions
	default_extensions = [	# Define cogs
		"commands.admin",
		"commands.games",
		"commands.general",
		"commands.angels",
		"events.general", # Causes an errror on any slash command, even commands from other cogs
		"events.angels",
	]
	for ext in default_extensions:
		logging.info(f"Loading extension: {ext}")
		await bot.load_extension(ext)	# Load cog

	# Database connection
	async def create_db_pool():	 # Connect to database
		try:
			bot.pg = await asyncpg.create_pool(
				database=settings.DATABASE_NAME,
				user=settings.DATABASE_USER,
				host=settings.DATABASE_HOST,
				password=settings.DATABASE_PASSWORD,
			)
		except AttributeError:
			missing_config()
		except asyncpg.exceptions.InvalidPasswordError:
			sql_authentication_error()
		except asyncpg.exceptions.InvalidCatalogNameError:
			sql_db_does_not_exist()

	# Create database pool
	await create_db_pool()

	# Create database tables if they do not exist
	from query.initialise_database import init_db, check_db
	try:
		await check_db(bot.pg)	# TODO: Create a better check
	except asyncpg.exceptions.UndefinedTableError:
		logging.info("User table does not exists, assuming empty database. Populating database...")
		await init_db(bot.pg)

	await bot.start(settings.DISCORD_TOKEN)


# Run robot
try:
	asyncio.run(main())
except AttributeError:
	missing_config()
except discord.errors.LoginFailure:
	logging.error("Invalid discord token.")
	correct_setting("DISCORD_TOKEN")
except KeyboardInterrupt:
	logging.info("Received keyboard interrupt, exiting...")
	quit()