selfdb.py

# -*- coding: utf-8 -*-
# seq 5000 | xargs -P100 -I% python2 selfdb.py k% v%

'''{prog} -- self-logging in-memory key-value storage

Usage:
  Display Keys
    {prog} 
  Get Value of Key
    {prog} some-key
  Set Value of Key
    {prog} some-key some-value
  Remove Key
    {prog} some-key ""
'''

import atexit
import sys
import logging
import os

__doc__ = __doc__.format(prog=os.path.basename(__file__))

DB = {}

logging.basicConfig(filename=__file__, format='%(message)s')

def main():
    args = sys.argv[1:]
    argc = len(args)
    if argc < 1:
        print(DB.keys())
    elif argc < 2:
        key = args[0]
        if key == '-h':
            print(__doc__)
        else:
            val = DB.get(key, None)
            print('%s = %s' % (key, val))
    else:
        key = args[0]
        val = args[1]
        if val:
            logging.error('DB[%s]=%s' % (repr(key), repr(val)))
        else:
            logging.error('DB.pop(%s,None)' % repr(key))

atexit.register(main)

#DB LOG

Pretty nice! I like the atexit trick. The downside of this approach is all the DB.pop() calls (and possibly redundant assignments) that will appear if one removes keys (and redefines then) frequently.

@lecram but you could just have another operation that "compresses" the log and spits it back out. I guess you'd have to lock the entire database to do that reliably though...