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
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
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
Turn SELECT queries returned by a query into links to execute them

datasette-query-links Turn SELECT queries returned by a query into links to execute them Installation Install this plugin in the same environment as D

Simon Willison 5 Apr 27, 2022
This repo contains the backend of the KMK project

KMK Backend This repository contains the backend part of the KMK project Demo Watch it on Youtube Getting started Pre-commit hooks After you cloned th

21 Nov 26, 2022
Python function to extract all the rows from a SQLite database file while iterating over its bytes, such as while downloading it

Python function to extract all the rows from a SQLite database file while iterating over its bytes, such as while downloading it

Department for International Trade 16 Nov 09, 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
pickleDB is an open source key-value store using Python's json module.

pickleDB pickleDB is lightweight, fast, and simple database based on the json module. And it's BSD licensed! pickleDB is Fun import pickledb

Harrison Erd 738 Jan 04, 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
Shelf DB is a tiny document database for Python to stores documents or JSON-like data

Shelf DB Introduction Shelf DB is a tiny document database for Python to stores documents or JSON-like data. Get it $ pip install shelfdb shelfquery S

Um Nontasuwan 35 Nov 03, 2022
Лабораторные работы по Postgresql за 5 семестр

Практикум по Postgresql ERD для заданий 2.x: ERD для заданий 3.x: Их делал вот тут Ниже есть 2 инструкции — по установке postgresql на manjaro и по пе

Danila 10 Oct 31, 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
Simpledb-py: Simple JSON database

Simpledb-py: Simple JSON database

тейлс 2 Feb 09, 2022
A NoSQL database made in python.

CookieDB A NoSQL database made in python.

cookie 1 Nov 30, 2022
A Python wrapper API for operating and working with the Neo4j Graph Data Science (GDS) library

gdsclient This repo hosts the sources for gdsclient, a Python wrapper API for operating and working with the Neo4j Graph Data Science (GDS) library. g

Neo Technology 101 Jan 05, 2023
EmployeeDB - Advanced Redis search functionalities on Python applied on an Employee management backend app

EmployeeDB - Advanced Redis search functionalities on Python applied on an Employee management backend app

Ahmad Bazzi 58 Oct 10, 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
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
ClutterDB - Extremely simple JSON database made for infrequent changes which behaves like a dict

extremely simple JSON database made for infrequent changes which behaves like a dict this was made for ClutterBot

Clutter Development 1 Jan 12, 2022
Simple json type database for python3

What it is? Simple json type database for python3! What about speed? The speed is great! All data is stored in RAM until saved. How to install? pip in

3 Feb 11, 2022
LightDB is a lightweight JSON Database for Python

LightDB What is this? LightDB is a lightweight JSON Database for Python that allows you to quickly and easily write data to a file Installing pip3 ins

Stanislaw 14 Oct 01, 2022