MrRabbit.Extensions.Configuration.Database 1.0.0

<h1 align="center">DatabaseConfigurationProvider</h1>

<p align="center"> <a href="https://dotnet.microsoft.com/"><img src="https://img.shields.io/badge/.NET-10-512bd4?logo=dotnet" alt=".NET 10"></a> <a href="https://www.nuget.org/packages/MrRabbit.Extensions.Configuration.Database"><img src="https://img.shields.io/nuget/v/MrRabbit.Extensions.Configuration.Database?logo=nuget&color=004880" alt="NuGet"></a> <a href="https://opensource.org/licenses/MIT"><img src="https://img.shields.io/badge/License-MIT-blue.svg" alt="License: MIT"></a> </p>

<p align="center"> A .NET library that extends the <code>Microsoft.Extensions.Configuration</code> system to support <b>database-backed configuration</b> sources with <b>read and write</b> capabilities.<br> Store and retrieve application settings from relational databases, with support for dynamic updates and strongly-typed options. </p>

<p align="center"> Feel free to report issues or suggest improvements to enhance the functionality and usability of this library. </p>

📑 Table of Contents

• ✨ Features
• 🔌 Supported Database Providers
• 🚀 Getting Started
  • Installation
  • Basic Configuration
  • Register Services
  • Reading Configuration
  • Writing Configuration
• ⚙️ Advanced Usage
  • Complex Objects
  • Collections and Arrays
  • Custom Table Configuration
  • Transactions
• 🗃️ Database Schema
• ⚠️ Limitations
• 📋 Changelog
• 📄 License

✨ Features

🔌 Supported Database Providers

🚀 Getting Started

Installation

Install the package via NuGet Package Manager:

dotnet add package MrRabbit.Extensions.Configuration.Database

Additionally, install the database provider package you intend to use:

For SQLite:

dotnet add package Microsoft.Data.Sqlite

For SQL Server:

dotnet add package Microsoft.Data.SqlClient

Basic Configuration

Add the database configuration provider to your IConfigurationBuilder:

using Microsoft.Extensions.Configuration;
using MrRabbit.Extensions.Configuration.Database;

var configuration = new ConfigurationBuilder()
    .AddDatabaseProvider(options =>
    {
        options.UseDatabase(Provider.SQLite, "Data Source=config.db");
    })
    .Build();

options.UseDatabase(Provider.SQLite, connectionString, registerDbProviderFactory: false);

Register Services

Configure options to be writable in your service collection:

using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Configuration;

builder.Services.ConfigureWritable<AppOptions>(builder.Configuration.GetSection("App"));

Reading Configuration

Use the standard IOptionsMonitor<T> interface to read configuration:

public class MyService
{
    private readonly IOptionsMonitor<AppOptions> _options;

    public MyService(IOptionsMonitor<AppOptions> options)
    {
        _options = options;
    }

    public void DoSomething()
    {
        var currentValue = _options.CurrentValue.ConnectionString;
    }
}

public class AppOptions
{
    public string ConnectionString { get; set; }
    public int MaxRetries { get; set; }
    public bool EnableLogging { get; set; }
}

Writing Configuration

Use the IWritableOptionsMonitor<T> interface to read and update configuration:

public class SettingsManager
{
    private readonly IWritableOptionsMonitor<AppOptions> _options;

    public SettingsManager(IWritableOptionsMonitor<AppOptions> options)
    {
        _options = options;
    }

    public void UpdateSettings()
    {
        var updated = new AppOptions
        {
            ConnectionString = "Server=localhost;Database=NewDb",
            MaxRetries = 5,
            EnableLogging = true
        };

        _options.Update(updated);

        // Changes are immediately reflected
        var current = _options.CurrentValue;
    }
}

⚙️ Advanced Usage

Complex Objects

The library supports nested configuration objects:

public class ApplicationSettings
{
    public DatabaseSettings Database { get; set; }
    public LoggingSettings Logging { get; set; }
}

public class DatabaseSettings
{
    public string ConnectionString { get; set; }
    public int Timeout { get; set; }
}

public class LoggingSettings
{
    public string Level { get; set; }
    public string Path { get; set; }
}

// Usage
services.ConfigureWritable<ApplicationSettings>(
    configuration.GetSection("App")
);

Collections and Arrays

Arrays and enumerable properties are fully supported:

public class ApiSettings
{
    public string[] AllowedOrigins { get; set; }
    public List<string> ApiKeys { get; set; }
}

// Usage
var settings = new ApiSettings
{
    AllowedOrigins = new[] { "http://localhost", "https://example.com" },
    ApiKeys = new List<string> { "key1", "key2", "key3" }
};

writableOptions.Update(settings);

Custom Table Configuration

To customize table and column names, you can configure the provider options:

using Microsoft.Extensions.Configuration;
using MrRabbit.Extensions.Configuration.Database;

var configuration = new ConfigurationBuilder()
    .AddDatabaseProvider(options =>
    {
        options.UseDatabase(Provider.SQLite, "Data Source=config.db")
            .UseTable(t => t
                .UseTable("MyTable")
                .UseKeyColumn("MyKey")
                .UseValueColumn("MyValue")
                .UseBaseKeyColumn("MyBaseKey"));
    })
    .Build();

Transactions

If your application requires transactional updates to configuration, you can modify the configuration table within a transaction scope and call ReloadDatabaseConfigurationProvider after commit to apply changes:

Entity Framework Example

internal class AppDbContext : DbContext
{
    public override async Task<int> SaveChangesAsync(CancellationToken cancellationToken = default)
    {
        var configurationChanged = ChangeTracker.Entries<ConfigurationEntry>().Any();
        var result = await base.SaveChangesAsync(cancellationToken);

        if (configurationChanged)
        {
            var configuration = this.GetService<IConfiguration>();
            configuration.ReloadDatabaseConfigurationProvider();
        }

        return result;
    }
}

🗃️ Database Schema

The provider stores configuration in a flat table named ConfigurationEntries:

Example data:

⚠️ Limitations

Database Providers

configuration.ReloadDatabaseConfigurationProvider();

SQL Server: Maximum key length is 450 characters due to index limitations on NVARCHAR(450).

Concurrency

The library does not implement optimistic concurrency control or locking mechanisms. In multi-instance deployments:

Performance

Schema Management

• The table is auto-created on first use
• Schema migrations are not automatically handled

Null Handling

📋 Changelog

1.0.0

• first release

📄 License

This project is licensed under the terms specified in the repository.