tlvdb

A TLV and file-based database implementation in Python

Intro

Why?

Have you ever asked how difficult is to implement a database? What are the trade-offs? Why isn't a database out there that fits all?

Well... I did, so I am giving it a try

Who is this project for?

I think that 'd be only me... but in general any developer that wants to implement a custom database might find it a good starting point

The basics

The main features are:

• TLV implemenation based on struct python module
• Binary file storage
• Hash index for items
• Thread-safe
• Defragmentation threshold

Example Usage

import os
import time
import unittest
import logging as lg

import tlvdb.util as util
from tlvdb.tlv import IPackable
from tlvdb.tlverrors import *
from tlvdb.tlvstorage import TlvStorage

class Person(IPackable):

    packaged = ["name", "numbers", "age"]

    def __init__(self, name="", numbers=[], age=-1):
        self.name = name
        self.numbers = numbers
        self.age = age


IFILE = "%s/data/test_obj.idx" % ROOT
ts = TlvStorage(IFILE)

p = Person("Andreas", ["0712312312", "0897408123"], 30)
pid = ts.create(p)
p2 = ts.read(pid, klass=Person)
lg.debug("Got %s" % p2)

Hacking

I am afraid you will have to look into the tests folder for now. A high level usage example would be test_objdb.py showing how you can serialize and store custom objects. A middle level use with raw TLV items can be found in test_tlvdb.py and low-level TLV packing/unpacking examples in test_tlv.py