DRN.Framework Overview

Architecture overview of DRN.Framework—a convention-based .NET framework for distributed reliable applications.

When to Apply

• •Understanding framework architecture and design principles
• •Deciding which package to use for a specific need
• •Learning core conventions shared across all packages
• •Extending or contributing to framework packages

Framework Stack

┌─────────────────────────────────────────────────────────────────┐
│                     DRN.Framework Stack                         │
├─────────────────────────────────────────────────────────────────┤
│  DRN.Framework.Hosting      │  Web hosting, security, endpoints │
│  DRN.Framework.Testing      │  Test contexts, containers        │
│  DRN.Framework.EntityFramework │ DbContext, migrations, IDs     │
│  DRN.Framework.Jobs         │  Background job scheduling        │
│  DRN.Framework.MassTransit  │  Message bus integration          │
├─────────────────────────────────────────────────────────────────┤
│  DRN.Framework.Utils        │  DI, settings, logging, IDs       │
├─────────────────────────────────────────────────────────────────┤
│  DRN.Framework.SharedKernel │  Domain, exceptions, JSON         │
└─────────────────────────────────────────────────────────────────┘

Package Purposes

Core Conventions

1. Attribute-Based Dependency Injection

All DRN projects use attribute-based service registration:

[Scoped<IMyService>]
public class MyService : IMyService { }

// Registration in module:
services.AddServicesWithAttributes();

See: drn-utils.md

2. Configuration Layering

Configuration applied in order:

1. •appsettings.json
2. •appsettings.{Environment}.json
3. •User secrets (development)
4. •Environment variables
5. •Mounted settings (/appconfig/)
6. •Command line arguments

3. JSON Conventions

System.Text.Json defaults overridden globally:

• •JsonSerializerDefaults.Web
• •JsonStringEnumConverter
• •AllowTrailingCommas = true
• •PropertyNameCaseInsensitive = true
• •CamelCase naming

4. Exception Handling

DRN exceptions map to HTTP status codes:

throw ExceptionFor.NotFound("User not found");

Package Dependency Graph

graph LR
    H[Hosting] --> U[Utils]
    EF[EntityFramework] --> U
    U --> SK[SharedKernel]
    T[Testing] --> H
    T --> EF

Key Points:

• •SharedKernel has NO dependencies (can be used in Contract layers)
• •Utils provides core infrastructure
• •Hosting/EntityFramework are peer packages
• •Testing depends on everything for integration tests

Module Pattern

Each assembly exposes a module for service registration:

public static class InfraModule
{
    public static IServiceCollection AddSampleInfraServices(this IServiceCollection sc)
    {
        sc.AddServicesWithAttributes();
        return sc;
    }
}

Reliability Characteristics

DRN Framework ensures:

• •Secure - Security headers, CSP, host filtering
• •Observable - Structured logging, scoped logs
• •Maintainable - Convention over configuration
• •Performant - Optimized defaults
• •Scalable - Distributed ID generation
• •Self-documenting - Endpoint metadata

Related Skills