Hexalith.KeyValueStorages 2.1.2

Hexalith Key/Value Storages

Overview

Hexalith Key/Value Storages is a flexible and extensible key-value storage library for .NET applications. It provides both in-memory and file-based storage implementations with support for optimistic concurrency control through Etags.

Purpose

The library offers a robust foundation for implementing key-value storage solutions with the following features:

• Generic type support for both keys and values
• Optimistic concurrency control using Etags
• Multiple storage implementations:
  • In-memory storage for fast, temporary data
  • File-based storage with JSON serialization
• Extensible architecture through interfaces
• Thread-safe operations
• Asynchronous API support

Getting Started

Prerequisites

• .NET 8.0 or later
• For file-based storage: Write permissions to the storage directory

Installation

Add the NuGet package to your project:

dotnet add package Hexalith.KeyValueStorages

Basic Usage

1. In-Memory Storage:

// Create an in-memory store
var store = new InMemoryKeyValueStore<string, MyData>();

// Add a value
long etag = await store.AddAsync("key1", new MyData(), CancellationToken.None);

// Retrieve a value
var result = await store.GetAsync("key1", CancellationToken.None);
MyData value = result.Value;
long currentEtag = result.Etag;

// Update a value
long newEtag = await store.SetAsync("key1", updatedData, currentEtag, CancellationToken.None);

2. JSON File Storage:

// Create a JSON file store
var store = new JsonFileKeyValueStorage<string, MyData>("data-directory");

// Operations are similar to in-memory store
string etag = await store.AddAsync("key1", new MyData(), CancellationToken.None);

Architecture

Core Interfaces

• IKeyValueStore<TKey, TValue, TEtag>: The main interface defining key-value store operations
• IKeySerializer<TKey>: Interface for key serialization
• IValueSerializer<TValue, TEtag>: Interface for value serialization with Etag support

Implementations

1. In-Memory Storage:

   • InMemoryKeyValueStore<TKey, TValue>: Simple in-memory implementation with long-based Etags
   • InMemoryKeyValueStore<TKey, TValue, TEtag>: Base class supporting custom Etag types

2. File Storage.

Features

Optimistic Concurrency

The library implements optimistic concurrency control using Etags:

• Each value has an associated Etag
• Updates require the current Etag
• Concurrent modifications are detected and prevented

Thread Safety

All implementations are thread-safe:

• In-memory store uses internal locking
• File-based store uses file system locks

Extensibility

Create custom implementations by:

1. Implementing IKeyValueStore<TKey, TValue, TEtag>
2. Extending base classes for specific storage types
3. Creating custom serializers implementing IKeySerializer<TKey> or IValueSerializer<TValue, TEtag>

Learn More

• Hexalith Key/Value Stores
• API Documentation

License

This project is licensed under the MIT License - see the file for details.