Tiny local JSON database for Python.

Overview

Pylowdb

Downloads Downloads

Simple to use local JSON database 🦉

# This is pure python, not specific to pylowdb ;)
db.data['posts'] = ({ 'id': 1, 'title': 'pylowdb is awesome' })

# Save to file
db.write()
# db.json
{
  "posts": [
    { "id": 1, "title": "pylowdb is awesome" }
  ]
}

Support me

Features

  • Lightweight
  • Minimalist and easy to learn API
  • Query and modify data using plain Python
  • Atomic write
  • Hackable:
    • Change storage, file format (JSON, YAML, ...) or add encryption via adapters

Install

pip install pylowdb

Usage

import os
from os import path
from pylowdb import (
    Low,
    JSONFile,
)

# Use JSON file for storage
file = path.join(os.getcwd(), 'db.json')
adapter = JSONFile(file)
db = Low(adapter)

# Read data from JSON file, this will set db.data content
db.read()

# If file.json doesn't exist, db.data will be None
# Set default data
# db.data = db.data or { 'posts': [] }
db.data = db.data or { 'posts': [] }

# Create and query items using plain Python

db.data['posts'].append('hello world')
db.data['posts'][0]

# You can also use this syntax if you prefer
posts = db.data['posts']
posts.append('hello world'

# Write db.data content to db.json
db.write()
// db.json
{
  "posts": [ "hello world" ]
}

More examples

For more example, see examples/ directory.

API

Classes

Pylowdb has classes (for synchronous adapters).

Low(adapter)

from pylowdb import (
    Low,
    JSONFile,
)
db = Low(JSONFile('file.json'))
db.read()
db.write()

Methods

db.read()

Calls adapter.read() and sets db.data.

Note: JSONFile adapter will set db.data to None if file doesn't exist.

db.data  # is None
db.read()
db.data # is not None

db.write()

Calls adapter.write(db.data).

db.data = { 'posts': [] }
db.write() # file.json will be { posts: [] }
db.data = {}
db.write() # file.json will be {}

Properties

db.data

Holds your db content. If you're using the adapters coming with pylowdb, it can be any type supported by json.dumbs.

For example:

db.data = 'string'
db.data = [1, 2, 3]
db.data = { 'key': 'value' }

Adapters

Pylowdb adapters

JSONFile

Adapter for reading and writing JSON files.

Low(JSONFile(filename))

Memory

In-memory adapter. Useful for speeding up unit tests.

Low(Memory())

YAMLFile

Adapter for reading and writing YAML files.

Low(YAMLFile(filename))

TextFile

Adapters for reading and writing text. Useful for creating custom adapters.

Third-party adapters

If you've published an adapter for pylowdb, feel free to create a PR to add it here.

Writing your own adapter

You may want to create an adapter to write db.data to YAML, XML, encrypt data, a remote storage, ...

An adapter is a simple class that just needs to expose two methods:

class CustomAdapter:
    read(self):
        # should return deserialized data
        pass
    write(self, data):
        # should return nothing
        pass

For example, let's say you have some async storage and want to create an adapter for it:

api = YourAPI()

class CustomAdapter:
    # Optional: your adapter can take arguments

    def __init__(self, *args, **kwargs):
        pass

    def read(self):
        data = api.read()
    return data

    def write(self, data):
        api.write(data)

adapter = CustomAdapter()
db = Low(adapter)

See pylowdb/adapters for more examples.

Custom serialization

To create an adapter for another format than JSON, you can use TextFile.

For example:

from pylowdb import (
    Adapter,
    Low,
    TextFile,
)
import yaml

class YAMLFile(Adapter):
    def __init__(self, filename: str):
        self.adapter = TextFile(filename)

    def read(self):
        data = self.adapter.read()
        if data is None:  
            return null
        else:
            return YAML.deserialize(data)

    def write(self, obj):
        return self.adapter.write(YAML.serialize(obj))

adapter = YAMLFile('file.yaml')
db = Low(adapter)

Limits

If you have large Python objects (~10-100MB) you may hit some performance issues. This is because whenever you call db.write, the whole db.data is serialized and written to storage.

Depending on your use case, this can be fine or not. It can be mitigated by doing batch operations and calling db.write only when you need it.

If you plan to scale, it's highly recommended to use databases like PostgreSQL, MySql, Oracle ...

Owner
Hussein Sarea
I love every thing creative,I adore anime and disney movies. Technology is my life, and I aspire to learn every single part about it.
Hussein Sarea
A fast ordered NoSQL database.

MerkavaDB Note This is still in active development. Things will change. If you are interested in helping out, or would like to see any particular feat

Adam Hopkins 6 Sep 29, 2022
Given a metadata file with relevant schema, an SQL Engine can be run for a subset of SQL queries.

Mini-SQL-Engine Given a metadata file with relevant schema, an SQL Engine can be run for a subset of SQL queries. The query engine supports Project, A

Prashant Raj 1 Dec 03, 2021
Decentralised graph database management system

Decentralised graph database management system To get started clone the repo, and run the command below. python3 database.py Now, create a new termina

Omkar Patil 2 Apr 18, 2022
A Painless Simple Way To Create Schema and Do Database Operations Quickly In Python

PainlessDB - Taking Your Pain away to the moon 🚀 Contribute · Community · Documentation 🎫 Introduction : PainlessDB is a Python-based free and open-

Aiden Ellis 3 Jul 15, 2022
This is a simple graph database in SQLite, inspired by

This is a simple graph database in SQLite, inspired by "SQLite as a document database".

Denis Papathanasiou 1.2k Jan 03, 2023
AWS Tags As A Database is a Python library using AWS Tags as a Key-Value database.

AWS Tags As A Database is a Python library using AWS Tags as a Key-Value database. This database is completely free* 💸

Oren Leung 42 Nov 25, 2022
TinyDB is a lightweight document oriented database optimized for your happiness :)

Quick Links Example Code Supported Python Versions Documentation Changelog Extensions Contributing Introduction TinyDB is a lightweight document orien

Markus Siemens 5.6k Dec 30, 2022
Oh-My-PickleDB is an open source key-value store using Python's json module.

OH-MY-PICKLEDB oh-my-pickleDB is a lightweight, fast, and intuitive data manager written in python 📝 Table of Contents About Getting Started Deployme

Adrián Toral 6 Feb 20, 2022
HTTP graph database built in Python 3

KiwiDB HTTP graph database built in Python 3. Reference Format References are strings in the format: { JanCraft 1 Dec 17, 2021

TelegramDB - A library which uses your telegram account as a database for your projects

TelegramDB A library which uses your telegram account as a database for your projects. Basic Usage from pyrogram import Client from telegram import Te

Kaizoku 79 Nov 22, 2022
Connect Django Project to PostgreSQL

An application for learning things with creating quizzes and flashcards.Django, PostgresSQL are used for this project.

Cena Ashoori 1 Jan 25, 2022
Tools for analyzing Git history using SQLite

git-history Tools for analyzing Git history using SQLite Installation Install this tool using pip: $ pip install git-history Usage This tool can be r

Simon Willison 128 Jan 02, 2023
Monty, Mongo tinified. MongoDB implemented in Python !

Monty, Mongo tinified. MongoDB implemented in Python ! Was inspired by TinyDB and it's extension TinyMongo

David Lai 523 Jan 02, 2023
Python function to query SQLite files stored on S3

sqlite-s3-query Python function to query a SQLite file stored on S3. It uses multiple HTTP range requests per query to avoid downloading the entire fi

Michal Charemza 189 Dec 27, 2022
Metrics-advisor - Analyze reshaped metrics from TiDB cluster Prometheus and give some advice about anomalies and correlation.

metrics-advisor Analyze reshaped metrics from TiDB cluster Prometheus and give some advice about anomalies and correlation. Team freedeaths mashenjun

3 Jan 07, 2022
Codeqlcompile - 自动反编译闭源应用,创建codeql数据库

codeql_compile 自动反编译闭源应用,创建codeql数据库 准备 首先下载ecj.jar和idea提供反编译的java-decompiler.ja

236 Jan 05, 2023
A Persistent Embedded Graph Database for Python

Cog - Embedded Graph Database for Python cogdb.io New release: 2.0.5! Installing Cog pip install cogdb Cog is a persistent embedded graph database im

Arun Mahendra 214 Dec 30, 2022
A NoSQL database made in python.

CookieDB A NoSQL database made in python.

cookie 1 Nov 30, 2022
A simple GUI that interacts with a database to keep track of a collection of US coins.

CoinCollectorGUI A simple gui designed to interact with a database. The goal of the database is to make keeping track of collected coins simple. The G

Builder212 1 Nov 09, 2021
A very simple document database

DockieDb A simple in-memory document database. Installation Build the Wheel Fork or clone this repository and run python setup.py bdist_wheel in the r

1 Jan 16, 2022