BetterStartupHook 1.0.0

Better Startup Hooks for .NET

The low-level api for startup hooks does not include dependency resolution for non-app assemblies. In other words hooks, dependencies to other assemblies than included in the injected application need extra dependency resolution logic.

Better-Startup-Hook allows to create startup hooks that automatically resolves additional dependencies.

How-does it work?

The project consists of a startup hook in BetterStartupHook.dll, whichs loads the actual logic to inject into the application from other assemblies and does all the extra logic to resolve the dependencies.

The BETTER_STARTUP_HOOKS environment variable can be used to specify a list of additional managed assemblies that contain a BetterStartupHook type with a public static void Initialize() method, each of which will be called in the order specified, before the Main entry point.

using System;

internal class BetterStartupHook
{
    public static void Initialize()
    {
       //Your custom logic.. 
    }
}

How-To create/use a BetterStartupHook

1. Implement your hook by creating a .Net class library project e.g.

using OpenTelemetry;
using OpenTelemetry.Trace;
using System;

internal class BetterStartupHook
{
    public static void Initialize()
    {
        //Your custom logic goes here...
        Console.WriteLiine("Hello World");
    }
}

2. Extend your .csproj to copy nuget references into your output folder

Add CopyLocalLockFileAssemblies as shown in the following

<Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
    <TargetFramework>net8.0</TargetFramework>
    <CopyLocalLockFileAssemblies>true</CopyLocalLockFileAssemblies>
  </PropertyGroup>

    ...
</Project>

Read more about CopyLocalLockFileAssemblies property

3. Register your better-startup-hook assembly

Windows:

BETTER_STARTUP_HOOKS="<path-to-betterstartuphook>\\MyStartupHook.dll

Linux:

BETTER_STARTUP_HOOKS="<path-to-betterstartuphook>\\MyStartupHook.dll

4. Register the BetterStartupHook assembly as your applications startup hook.

Windows:

DOTNET_STARTUP_HOOKS="<path-to-betterstartuphook>\\BetterStartupHook.dll

Linux:

DOTNET_STARTUP_HOOKS="<path-to-betterstartuphook>/BetterStartupHook.dll

Contribute

This is an open source project, and we gladly accept new contributions and contributors.

License

Licensed under Apache 2.0 license. See LICENSE for details.