Archon 0.1.2

Archon

Roslyn analysers for enforcing architectural rules in C# projects.

Installation

dotnet add package Archon

Features

Archon provides Roslyn analysers that enforce namespace-based architectural rules:

ARCHON001: Internals Are Internal

Ensures that all types within namespaces containing .Internal are properly restricted with internal or private access modifiers. This prevents accidental exposure of internal implementation details.

• Severity: Error
• Namespace Pattern: *.Internal* (e.g., MyApp.Internal, MyApp.Services.Internal)
• Allowed Modifiers: internal, private, private protected
• Special Handling: Nested types are exempt if their containing type is already internal or private

ARCHON002: Publics Are Public

Ensures that top-level types within namespaces containing .Public are appropriately exposed with public or protected access modifiers. This enforces discoverability of your public API surface.

• Severity: Warning
• Namespace Pattern: *.Public* (e.g., MyApp.Public, MyApp.Api.Public)
• Required Modifiers: public, protected, protected internal
• Scope: Only applies to top-level types (nested types are exempt)

Usage

Once installed, the analysers will automatically run during compilation and highlight violations in your IDE.

Configuration

Configure severity levels in your .editorconfig:

[*.cs]
# Enforce internal types in .Internal namespaces (default: error)
dotnet_diagnostic.ARCHON001.severity = error

# Enforce public types in .Public namespaces (default: warning)
dotnet_diagnostic.ARCHON002.severity = warning

Example

namespace MyApp.Internal
{
    // ✅ Correct - internal type in .Internal namespace
    internal class InternalService { }

    // ❌ ARCHON001 violation - public type in .Internal namespace
    public class PublicService { }
}

namespace MyApp.Public
{
    // ✅ Correct - public type in .Public namespace
    public class PublicApi { }

    // ❌ ARCHON002 violation - internal type in .Public namespace
    internal class InternalApi { }
}

Development

Prerequisites

• .NET 10.0 SDK or later
• (Optional) act for local CI/CD testing

Building

cd src
dotnet restore Archon.slnx
dotnet build Archon.slnx

Testing

cd src/Archon.Tests.Unit/bin/Release/net10.0
dotnet Archon.Tests.Unit.dll

Local CI/CD Testing

Test the CI pipeline locally:

./scripts/test-ci.sh

Test the CD pipeline locally:

./scripts/test-cd.sh

Licence

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

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.