WillowAnk Solution

ASP.NET Core document conversion with dependency injection

One call, AddDocToolkit(), registers DocToolkit with ASP.NET Core dependency injection. This guide covers the install, the settings, background services and tests.

var builder = WebApplication.CreateBuilder(args);
builder.Services.AddDocToolkit();

var app = builder.Build();

Install and register

  • The extensions package brings the core package with it, so you do not need to reference both.
  • One call registers all 21 interfaces the package ships, each a thin wrapper over the matching static class.
  • An interface differs from its static class only by the leading I: IPdfEditor wraps PdfEditor.
  • All are singletons, which is safe because none of them holds state.
  • They are registered with TryAdd, so your own implementation, registered first, wins.

Set it once

  • DocToolkitOptions holds application-wide settings, so they are not repeated at every call site.
  • AllowRemoteImageDownload is the master switch for remote images. It is false unless you set it.
  • Page sets the paper once. The default is PageSetup.A4.
  • A call that names a page still wins over the configured one.
  • Options are read on each call, not once at startup. A change in appsettings.json with reloadOnChange takes effect on the next conversion, with no restart.

Background services and tests

  • A BackgroundService can take these services straight in its constructor, because they are stateless singletons.
  • Wrapping them in a scope would imply a lifetime problem that is not there.
  • In a test, substitute the interface, for example IHtmlToPdfConverter, so the test does not spend time rendering a real PDF.
  • Tests about the conversion itself should call the real thing. It needs no fixtures and no network.

What it will not do

  • The extensions package adds no capability. Everything it exposes is available statically; it exists for substitutability and configuration.
  • For a console app, a script or a library, use Ank.DocToolkit and call the static classes.

Install

dotnet add package Ank.DocToolkit.Extensions.DependencyInjection

Read it in the DocToolkit docsNuGetGitHub

More guides

Everything DocToolkit converts