multifeeder/simpledatabase.py

from os import environ, mkdir
from os.path import exists
from pathlib import Path 
from logging import DEBUG, INFO, basicConfig, getLogger 
from json import dumps, loads 

class SimpleDatabase(dict):
	"""A simple database.
	It is a dictionary which saves to disk on all writes. It is optimised for
	ease of hacking and accessibility and not for performance or efficiency.

	Written by decentral1se, as part of:
	https://git.vvvvvvaria.org/decentral1se/xbotlib/src/branch/main/xbotlib.py
	"""

	def __init__(self, filename, log, *args, **kwargs):
		"""Initialise the object."""
		self.filename = Path(filename).absolute()
		self.log = getLogger(__name__)

		self._loads()
		self.update(*args, **kwargs)

	def _loads(self):
		"""Load the database."""
		if not exists(self.filename):
			return

		try:
			with open(self.filename, "r") as handle:
				self.update(loads(handle.read()))
		except Exception as exception:
			message = f"Loading file storage failed: {exception}"
			self.log.error(message, exc_info=exception)
			exit(1)

	def _dumps(self):
		"""Save the databse to disk."""
		try:
			with open(self.filename, "w") as handle:
				handle.write(dumps(self, indent=4, sort_keys=True))
		except Exception as exception:
			message = f"Saving file storage failed: {exception}"
			self.log.error(message, exc_info=exception)
			exit(1)

	def __setitem__(self, key, val):
		"""Write data to the database."""
		super().__setitem__(key, val)
		self._dumps()

	def __delitem__(self, key):
		"""Remove data from the database."""
		super().__delitem__(key)
		self._dumps()

	def update(self, *args, **kwargs):
		"""Update the database."""
		for k, v in dict(*args, **kwargs).items():
			self[k] = v
		self._dumps()