Integrate NDepend into your .Net Core projects !

Introduction

In computer science and software engineering in particular, software quality is an overall assessment of software, based on many indicators.

The completeness of the features, the correction and precision of the results, the reliability, the fault tolerance, the facility and the flexibility of its use, the simplicity, the extensibility, the compatibility and the portability, the facility of correction and transformation, the performance, consistency and integrity of the information it contains are all quality factors.

In software engineering, factorization of data and code is the universal means of obtaining quality.

We will talk in this article about NDepend, a tool to help software developers to achieve a high level of quality of their programs.

What is NDepend ?

 

NDepend was created by Patrick Smacchia in 2004, it became commercial in 2007 and evolved a lot since.

It does static code analysis for .NET and you can try it free for 14 days.

NDepend can be used in standalone or integrated Visual Studio mode.

This tool gives you one-click access to many metrics in your code with a graphical representation. Interesting!

With the dashboard the most interesting feature of NDepend is the query language on which it is built: CQLinq

But before let’s take a look on the installation process.

Installation

Installing the NDepend extension for Visual Studio is really easy, download it and install like this by clicking on Visual Studio Extension Installer and then select the Visual Studio version you to install on:

The great thing about NDepend is the ease with which you can get started and the excellent documentation available in their website. There are online videos, tutorials, screenshots, step by step explanations and you cannot go wrong with it.

For more details you can go here for: https://www.ndepend.com/docs/getting-started-with-ndepend#Tuto

Running NDepend

You can run NDepend in standalone with VisualNDepend.exe executable (in the same installation directory than the Visual Studio Extension executable) or run the extension in Visual Studio from the menu:

When you expend the menu you can access to NDepend features.

Let’s see how Dashboard looks like:

On the same screen, NDepend provides many many metrics like :

  • Technical Debt
  • Lines of code
  • Comments
  • Issues
  • Programming rules
  • Code coverage
  • Quality gates
  • And more other features

It provides really huge analysis of your code, you can at anytime take a look at a little summary and recompute your dashboard by clicking on the colored circle at bottom right of your screen, very convenient!

 

Let’s see another crazy feature of NDepend:  CQLinq

CQLinq, which stands for Query Code LINQ, is a query language that you can execute on an abstract model of your code. In concrete terms, you can query your code the same way you would query the views or tables of a database. For example, to search all class constructors, I wrote the following query:

from m in Methods 
where m.IsConstructor
select m

If you want to write your query, go on the NDepend menu, select “Rules” and View “Editor Panel“:

It open a little window where you can type your query, at the same time, the result is displayed at the bottom, nice isn’t it? 🙂

 

There is also VSTS integration:

You can integrate NDepend to your TFS CI/CD process by leveraging a VSTS extension and adding it to your build definition. You can also define a Quality Gate for your project, and fail the build when code quality is not met.

There are also TeamCity, Jenkins, SonarQube and FinalBuilder integration if you don’t use VSTS.

Conclusion

I did not introduce every features of NDepend because it’s a very big and complete product, I chose the most interesting features according to me.

I didn’t precise that all NDepend results can be diff-ed since a baseline:  https://www.ndepend.com/docs/code-diff-in-visual-studio

I didn’t dig into Technical-Debt capabilities:
https://www.ndepend.com/docs/technical-debt that NDepend has facilities to explore dependencies with code graph and DSM (Dependency Structure Matrix)
https://www.ndepend.com/docs/visual-studio-dependency-graph
https://www.ndepend.com/docs/dependency-structure-matrix-dsm
https://www.ndepend.com/docs/cqlinq-features#Dependencies that NDepend can import code coverage data and use it in some rule…
https://www.ndepend.com/docs/treemap-visualization-of-code-metrics#Color

I honestly think NDepend is very powerful and very easy to use. The CQLinq language and the NDepend dashboard are in fact the best features of the tool and in addition I have found nothing equivalent at this level.

However, because NDepend doesn’t correct code for you, I suggest to keep using Resharper that can work in synergy with NDepend. There are few overlap between the NDepend and Resharper rules-sets, while Resharper is more focused on details inside methods body, NDepend focuses more on code structure and overall quality.

The NDepend team is very active and we can expect a lot of good developments in future versions.

I thank Patrick Smacchia, for giving me the opportunity to test his product that I find really excellent.

Patrick when a NDepend-like for SPAs ? 😉

Injection Dependency: Bring your own container in .NET Core Web API, example with Simple Injector

Introduction of Simple Injector

Simple Injector is an easy-to-use Dependency Injection (DI) library for .NET that supports .NET Core, Xamarin, Mono and Universal apps. Simple Injector is easily integrated with frameworks such as Web API, MVC, WCF, ASP.NET Core and many others. It’s easy to implement the dependency injection pattern with loosely coupled components using Simple Injector.

Why Simple Injector? It’s simple to use, free, fast, support advanced generics types, and provide powerful diagnostics services.

If you want to know more about you can check the documentation here: https://simpleinjector.readthedocs.io/en/latest/quickstart.html

Installation of Simple Injector in ASP.NET Core WebAPI

Select and Install SimpleInjector.Integration.AspNetCore.Mvc from “Manage Nuget packages” panel

or type the following command in “Package manager console”:

Install-Package SimpleInjector.Integration.AspNetCore.Mvc -Version 4.0.12

Configuration of Simple Injector in ASP.NET Core WebAPI

  • Import SimpleInjector, SimpleInjector.Lifestyles and SimpleInjector.Integration.AspNetCore.Mvc namespaces
  • Add a Container property in your class Startup.cs
  • Register your service with its appropriate Interface, Simple Injector supports concrete injection (the class without its interface), you can set Lifestyle.Scoped, Lifestyle.Singleton or Lifestyle.Transient
  • Optionnally add Verify method,  (after RegisterMvcControllers method in Configure method) it iterates registered service to check if something is not correct, will throw an exception before any execution of the program
  • Add SimpleInjectorControllerActivator that implements IControllerActivator to provide dependency injection resolution in controllers constructor
  • Then add the extension method UseSimpleInjectorAspNetRequestScoping that ASP.NET requests into Simpleinjector’s scoped lifestyle

Example:

public interface IHelloWorldService
{
   string HelloWorld();
}
public class HelloWorldService : IHelloWorldService
{
   public string HelloWorld()
   {
      return "Hello world";
   }
}
[Route("api/[controller]")]
public class HelloController : Controller
{
   private IHelloWorldService _helloService;

   public HelloController(IHelloWorldService helloService)
   {
      _helloService = helloService;
   }

   [HttpGet]
   public string Get()
   {
      return _helloService.HelloWorld();
   }
}
public class Startup
{
   private Container container = new Container();

   public Startup(IConfiguration configuration)
   {
      Configuration = configuration;
   }

   public IConfiguration Configuration { get; }

   // This method gets called by the runtime. Use this method to add services to the container.
   public void ConfigureServices(IServiceCollection services)
   {
      services.AddMvc();

      // Default lifestyle scoped + async
      // The recommendation is to use AsyncScopedLifestyle in for applications that solely consist of a Web API(or other asynchronous technologies such as ASP.NET Core)
      container.Options.DefaultScopedLifestyle = new AsyncScopedLifestyle();

      // Register services
      container.Register<IHelloWorldService, HelloWorldService>(Lifestyle.Scoped); // lifestyle can set here, sometimes you want to change the default lifestyle like singleton exeptionally

      // Register controllers DI resolution
      services.AddSingleton<IControllerActivator>(new SimpleInjectorControllerActivator(container));

      // Wrap AspNet requests into Simpleinjector's scoped lifestyle
      services.UseSimpleInjectorAspNetRequestScoping(container);

  }

   // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
   public void Configure(IApplicationBuilder app, IHostingEnvironment env)
   {
      if (env.IsDevelopment())
      {
         app.UseDeveloperExceptionPage();
      }

      app.UseMvc();

      container.RegisterMvcControllers(app);

      // Verify Simple Injector configuration
      container.Verify();
   }
}

 

Execution:

 

We did it! we brought our own dependency injection container 🙂

Injection Dependency: Bring your own container in .NET Core console App, example with Simple Injector

Introduction of Simple Injector

Simple Injector is an easy-to-use Dependency Injection (DI) library for .NET that supports .NET Core, Xamarin, Mono and Universal apps. Simple Injector is easily integrated with frameworks such as Web API, MVC, WCF, ASP.NET Core and many others. It’s easy to implement the dependency injection pattern with loosely coupled components using Simple Injector.

Why Simple Injector? It’s simple to use, free, fast, support advanced generics types, and provide powerful diagnostics services.

If you want to know more about you can check the documentation here: https://simpleinjector.readthedocs.io/en/latest/quickstart.html

Installation of Simple Injector in a console app

Select and Install it from “Manage Nuget packages” panel

or type the following command in “Package manager console”:

PM> Install-Package SimpleInjector -Version 4.0.12

Configuration of Simple Injector in a console app

  • Import SimpleInjector and SimpleInjector.Lifestyles namespaces
  • Add a static Container property in your class Program
  • Register your service with its appropriate Interface, Simple Injector supports concrete injection (the class without its interface)
  • Optionnally add Verify method, it iterates registered service to check if something is not correct, will throw an exception before any execution of the progam
  • Then use GetInstance method to get your service

Example :

public interface IMyService
{
   string HelloWorld();
}
public class MyService: IMyService
{
   public string HelloWorld()
   {
      return "Hello world!";
   }
}
using SimpleInjector;
using System;

namespace ConsoleAppDemoWithSimpleInjector
{
   class Program
   {
      static readonly Container container;

      static Program()
      {
         container = new Container();

         container.Register<IMyService, MyService>();

         container.Verify();
      }

      static void Main(string[] args)
      {
         var service = container.GetInstance<IMyService>();
         Console.WriteLine(service.HelloWorld());
         Console.ReadLine();
      }
   }
}

Execution:

Configuration of Simple Injector in a console app thats runs undefinitely

In the absence of any framework code, you are yourself responsible to tell Simple Injector that certain code must run in isolation. This can be done with Scoping. There are two types of scoped lifestyles that can be used. ThreadScopedLifestyle allows wrapping code that runs on a single thread in a scope, where AsyncScopedLifestyle allows wrapping a block of code that flows asynchronously (using async await).

The following example demonstrates a simple Console application that runs indefinitely, and executes a request every second. The request is wrapped in a scope:

class Program
{
   static readonly Container container;

   static Program()
   {
      container = new Container();
      container.Options.DefaultScopedLifestyle = new ThreadScopedLifestyle();

      container.Register<IMyService, MyService>();

      container.Verify();
   }

   static void Main(string[] args)
   {
      while (true)
      {
         using (ThreadScopedLifestyle.BeginScope(container))
         {
            var service = container.GetInstance<IMyService>();

            Console.WriteLine(service.HelloWorld());
         }

         Thread.Sleep(TimeSpan.FromSeconds(1));
      }
   }
}

By default the lifecycle of our service is Transient, it means that a new instance will be created each we ask an instance of our service, else you can set Singleton.

Transient lifestyle

container.Register<IMyService, MyService>(Lifestyle.Transient);

or

container.Register<IMyService, MyService>();

Singleton lifestyle

container.Register<IMyService, MyService>(Lifestyle.Singleton);

Example that display Guid of the instance:

public class MyService: IMyService
{
   private Guid _guid;

   public MyService()
   {
      _guid = Guid.NewGuid();
   }

   public string HelloWorld()
   {
      return $"Hello world! instance: {_guid}";
   }
}

Execution :

Transient lifestyle

Guid are not identicals

Singleton lifestyle

Guid are identicals

 

Simple isn’it ? 🙂