# RAIC.Extensions.Configuration.EntityFrameworkCore

This library is a `Microsoft.Extensions.Configuration.IConfigurationProvider` that reads settings from a `DbSet<ISetting> Settings` property 
present on your Entity Framework Core `DbContext`.

## Goals
1. Usable with minimal constraints on your entity model
1. Follows conventional configuration patterns 
1. `IOptionsMonitor` update support through optional opt-in services (see `RAIC.Extensions.Configuration.EntityFrameworkCore.PostgreSQL` & `RAIC.Extensions.Configuration.EntityFrameworkCore.SqlServer`)


## Requirements
* .NET 8


## Gotchas
* Setting values cannot be `null` (as signified by the `RequiredAttribute` on `ISetting.Value`)
* Setting keys should not contain the `=` character (similar to `CommandLineConfigurationProvider` & `EnvironmentVariablesConfigurationProvider`)


## Usage Example

```csharp

using RAIC.Extensions.Configuration.EntityFrameworkCore.Extensions;

public record Setting : ISetting
{
    [Key]
    public required string Key { get; set; }

    [Required]
    public required string Value { get; set; }
}

public class MyDbContext(DbContextOptions<MyDbContext> options) : DbContext(options), ISettingsDbContext<DbSet<Setting>>, ISettingsDbContextFactory<MyDbContext>
{
    public DbSet<Setting> Settings { get; set; }

    public static MyDbContext Create(DbContextOptions<MyDbContext> options) => new(options);
}

var builder =  Host.CreateApplicationBuilder(args) // or  WebApplication.CreateBuilder(args); 

// build an initial configuration
builder.Configuration.AddJsonFile("appsettings.json")
                     ...
                     .AddUserSecrets<Program>(); // or whereever your connection string lives

// obtain connection string from preliminary config so can initialise other settings from DbContext
builder.Configuration.AddDbContext<MyDbContext>(dbContextOptions => dbContextOptions.UseNpgsql(builder.Configuration.GetConnectionString("Default")));

...

await builder.Build().RunAsync(); // use config as normal

```

Read more about [Configuration](https://docs.microsoft.com/en-us/dotnet/core/extensions/configuration) on the Microsoft Docs site.