Alethic.Node.AspNet 1.0.1-pre.25

Alethic.Node.AspNet

Node.js in an ASP.NET (System.Web) application on .NET Framework, over Alethic.Node's pool: a pool that needs no container, work done for a request from the engine's thread, JavaScript that fetches from the site it runs in, and an application's pages served from System.Web routes. For components on Web Forms pages, see Alethic.Node.AspNet.Components.

dotnet add package Alethic.Node.AspNet
dotnet add package Microsoft.JavaScript.LibNode.win-x64

The pool

AspNetNode.Pool works with no setup: one engine. To change it, the alethic.node section in web.config:

<configSections>
  <section name="alethic.node" type="Alethic.Node.AspNet.NodeSection, Alethic.Node.AspNet" />
</configSections>

<alethic.node engineCount="2" maxConcurrencyPerEngine="4" acquireTimeout="00:00:10" />

A site with a container supplies its own pool, with every option, through HttpRuntime.WebObjectActivator.

Work for a request

var request = new NodeRequest(Context);
var html = await request.RunAsync(module, async exports =>
    (string)await ((JSPromise)request.Call(exports["render"], exports, props)).AsTask());

The work runs on an engine's thread. What it needs done as the request, with HttpContext.Current in place, it hands back with request.InvokeAsync(...), and the request's thread does it. RunAsync is for an Async="true" page; Run blocks, for one that is not.

JavaScript called through request.Call can fetch the site, and the request answers it in process as the visitor, through the site's own handler for the path: GET and HEAD, cookies, a text response.

Pages from a fetch handler

protected void Application_Start(object sender, EventArgs e)
{
    var app = new FetchRequestHandler(NodeModuleSource.FromFile(HostingEnvironment.MapPath("~/App_Data/app/app.cjs")));
    RouteTable.Routes.MapNode("about", app);
    RouteTable.Routes.MapNode("parks/{parkRef}", app);
}

The application is a CommonJS bundle whose default export has a fetch(request, env, ctx) function; Alethic.Node.Http says what it sees, and the same bundle serves from ASP.NET Core. Its response is the site's, status included. Requests no route matches go on to the site's pages; a catch-all route needs RouteTable.Routes.Ignore("{resource}.axd/{*pathInfo}") ahead of it.

One Node per process

ASP.NET restarts an application in a new AppDomain of the same process, where Node cannot start again. Keep the site from restarting in place (<httpRuntime fcnMode="Disabled" />) and recycle the application pool to deploy.