Carubbi.ServiceLocator 2.0.0

Carubbi.ServiceLocator

A simple helper that implements the Service Locator pattern, resolving concrete implementations for interfaces or well-known keys through Microsoft.Extensions.Configuration.

Features

• Resolve interfaces to concrete types configured in any IConfiguration source (JSON, environment variables, in-memory, etc.) without a compile-time reference to the implementing project.
• Resolve by friendly type name (including closed generics such as "IRepository[Customer]") or by arbitrary configuration key.
• Constructor injection of parameters through reflection.
• Singleton resolution through a public static GetInstance() factory method.
• Plugin discovery: scan a directory for assemblies exposing classes that implement both IPlugin and a contract T.
• Strict error handling: missing sections, missing keys and unloadable types throw descriptive exceptions instead of failing silently.

Installation

dotnet add package Carubbi.ServiceLocator

Requires .NET 10.0 or later.

Usage

Given an appsettings.json:

{
  "Implementations": {
    "IMessageService": "MyApp.Services.EmailMessageService, MyApp",
    "IRepository[int]": "MyApp.Data.IntRepository, MyApp"
  },
  "AppSettings": {
    "ConnectionString": "Server=.;Database=MyDb;Trusted_Connection=True;"
  }
}

Resolve implementations:

using Microsoft.Extensions.Configuration;
using Carubbi.ServiceLocator;

var configuration = new ConfigurationBuilder()
    .AddJsonFile("appsettings.json")
    .Build();

var resolver = new ImplementationResolver(configuration);

// By interface type name
IMessageService service = resolver.Resolve<IMessageService>();

// By explicit key with constructor parameters
var repository = resolver.Resolve<IRepository<int>>("IRepository[int]");

// Singleton via a public static GetInstance() factory method
var singleton = resolver.ResolveSingleton<IMessageService>();

Read key/value settings from a section:

var settings = new AppSettings(configuration, "AppSettings");
string connectionString = settings["ConnectionString"];

Discover plugins:

List<IGreeter> plugins = PluginLocator.GetPlugins<IGreeter>("path/to/plugins");

Note: type names must be resolvable by Type.GetType. Prefer assembly-qualified names (Namespace.Class, AssemblyName) and make sure the implementing assembly is available to the application.

Building and testing locally

Prerequisites:

• .NET SDK 10.0 or later

dotnet build -c Release
dotnet test --solution Carubbi.ServiceLocator.sln

The unit tests run entirely in memory; no Docker or external infrastructure is required.

Releases

Releases are published to nuget.org automatically by the publish workflow whenever a tag matching v* is pushed:

git tag v2.0.0
git push origin v2.0.0

License

Distributed under the MIT License.