lemon24

This gist tracks the creation of an almost fully functional sqlite3 server in Python 3, using only the multiprocessing.managers standard library module.

But why?

To see if it can be done.
To learn about multiprocessing managers.
Aside from whole-database locking, SQLite (maybe, see below) supports table-level locking between multiple connections in the same process to the same database. A "SQLite server" makes it possible for users in different processes to use SQLite connections that live in the same process.

	import timeit
	import shutil
	import textwrap
	import functools

	import bs4

	# reader 0.18
	from reader import make_reader

	import timeit
	import shutil
	import textwrap
	import functools

	import bs4

	# reader 0.18
	from reader import make_reader

	>>> from reader import make_reader
	>>>
	>>> reader = make_reader('db.sqlite')
	>>> reader.add_feed('http://www.hellointernet.fm/podcast?format=rss')
	>>> reader.update_feeds()
	>>>
	>>> entries = list(reader.get_entries(feed='http://www.hellointernet.fm/podcast?format=rss'))
	>>> [e.title for e in entries]
	['H.I. #108: Project Cyclops', 'H.I. #107: One Year of Weird', ...]
	>>>

	import string
	import random

	from reader import make_reader, SearchError

	reader = make_reader("db.sqlite")


	def queries():
	for i in range(256):

	>>> import math, collections
	>>> from reader import *
	>>>
	>>> reader = make_reader('db.sqlite')
	>>>
	>>> def word_count_magnitude(text):
	... if not text:
	... return 0
	... return int(math.log10(len(text.split())))
	...

	import shutil

	import mutagen

	shutil.copy('original.mp4', 'new.mp4')

	# mutagen.File knows how to open any file (works with both MP4 and MP4):
	#
	# https://mutagen.readthedocs.io/en/latest/user/gettingstarted.html
	# https://mutagen.readthedocs.io/en/latest/api/base.html#mutagen.File

	import collections
	import textwrap
	import functools


	class Query(collections.OrderedDict):

	indent_prefix = ' '
	default_separators = dict(WHERE='AND', HAVING='AND')

	"""
	Run `reader update` and `reader update --new-only && reader search update``
	in parallel, like cron would, but at a "scaled down" timeframe.

	We use vcrpy to avoid making network calls.

	https://github.com/lemon24/reader/issues/175

	"""
	import os

	import os
	import os.path
	import time
	import sys
	import random
	import itertools
	from datetime import datetime
	from subprocess import run
	from threading import Thread
	import threading