PosInformatique.AspNetCore.Server.AspNet

PosInformatique.AspNetCore.Server.AspNet is a library to host ASP .NET Core Web API on ASP .NET
non-core (WebForms and MVC) infrastructure based on the .NET Framework.

Architecture

The PosInformatique.AspNetCore.Server.AspNet is an ASP .NET non-core IHttpHandler
which is executed depending of configured routes in the ASP .NET non-core infrastructure.
When the PosInformatique.AspNetCore.Server.AspNet IHttpHandler internal implementation
is called, the HTTP query is send to the ASP .NET Core infrastructure which execute
the query with the same behavior if it was hosted in a dedicated IIS, Console or Kestrel host.

Installing from NuGet

The PosInformatique.AspNetCore.Server.AspNet is available directly on the
NuGet official website.
To download and install the library to your Visual Studio project using the following NuGet command line

Install-Package PosInformatique.AspNetCore.Server.AspNet

Setting up

In the an new ASP .NET Web Forms/MVC non-core project install the ASP .NET Core 2.x infrastructure
using the following NuGet command:

Install-Package Microsoft.AspNetCore
Install-Package Microsoft.AspNetCore.Mvc

After adding the PosInformatique.AspNetCore.Server.AspNet package on your ASP .NET
WebForms or MVC non-core project, inside the Application_Start of your HttpApplication
class builds and start an ASP .NET Core IWebHost instance using the classic
WebHost.CreateDefaultBuilder() and related API
(Startup class, additional services,…).
Instead to choose Kestrel or IIS to host your ASP .NET Core application,
call the UseAspNet() method to host your ASP .NET Core application
on the ASP .NET non-core infrastructure.

The UseAspNet() requires to defines the base routes which will be intercepted
and process by the ASP .NET Core infrastructure instead of ASP .NET non-core.

This is an example of a Global.asax.cs code behind which builds, start an ASP .NET
Core application and redirect all the request starting by /api and /swagger URLs
to the ASP .NET Core application:

public class Global : System.Web.HttpApplication
{
    protected void Application_Start(object sender, EventArgs e)
    {
        WebHost.CreateDefaultBuilder()
            .UseAspNet(options =>
            {
                options.Routes.Add("api");
                options.Routes.Add("swagger");
            })
            .UseStartup<Startup>()
            .Start();
    }
}

You can configure your ASP .NET Core application as usual with the Startup class
by registering additional services.
This is an example of a Startup class which register the ASP .NET Core MVC infrastructure
and the Swashbuckle.AspNetCore
extensions to add the documentation using Swagger UI.

public class Startup
{
    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();
        services.AddSwaggerGen(c =>
        {
            c.SwaggerDoc("v1", new Info { Title = "My API", Version = "v1" });
            // Set the comments path for the Swagger JSON and UI.
            var xmlFile = $"{Assembly.GetExecutingAssembly().GetName().Name}.xml";
            var xmlPath = Path.Combine(AppContext.BaseDirectory, "bin", xmlFile);
            c.IncludeXmlComments(xmlPath);
        });
    }
    // 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(routes =>
        {
            routes.MapRoute(
                name: "default",
                template: "{controller=Home}/{action=Index}/{id?}");
        });
        // Enable middleware to serve generated Swagger as a JSON endpoint.
        app.UseSwagger();
        // Enable middleware to serve swagger-ui (HTML, JS, CSS, etc.),
        // specifying the Swagger JSON endpoint.
        app.UseSwaggerUI(c =>
        {
            c.SwaggerEndpoint("/swagger/v1/swagger.json", "My API V1");
        });
    }
}
`

Limitations

You have to becareful to use ONLY the components and service of the ASP .NET Core inside
your controllers implementation.
Avoid to access to the components or services of ASP .NET non-core from your controllers
implementations. For example, be sure to access to the ASP .NET Core HttpContext
inside your controllers code and do not use the ASP .NET non-core HttpContext.

As is shown in the previous architecture drawing, in your controllers code you should
use only to the ASP .NET Core API even you can access to the ASP .NET non-core infrastructure API.

ASP .NET Core 3.x

Because ASP .NET Core 3.x is based only on the .NET Core 3.0 runtime (and not
on the .NET Standard 2.0 like before with the ASP .NET Core 2.x), this library
can not be used to host ASP .NET Core 3.x Web API on ASP .NET non-core infrastructure.

ASP .NET Core Razor views

Currently the PosInformatique.AspNetCore.Server.AspNet can only work with raw
ASP .NET Core infrastructure and for the Web API controllers implementations.
It is not possible to use this library with the MVC razor views, because
the Visual Studio project use the ASP .NET non-core web compiler.

Contributions

Do not hesitate to clone my code and submit some changes…
It is a open source project, so everyone is welcome to improve this library…
By the way, I am french… So maybe you will remarks that my english is not really fluent…
So do not hesitate to fix my resources strings or my documentation… Merci !

Thanks

I want to thank the DiliTrust company to test and gave me their
feedback of this library for their ASP .NET WebForms applications which embedded
API developped on ASP .NET Core Web.