Plugins

Plugins

Starting with ASF V4, the program includes support for custom plugins that can be loaded during runtime. Plugins allow you to customize ASF behaviour, for example by adding custom commands, custom trading logic or whole integration with third-party services and APIs.

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For users

ASF loads plugins from plugins directory located in your ASF folder. It's a recommended practice to maintain a dedicated directory for each plugin that you want to use, which can be based off its name, such as MyPlugin. Doing so will result in the final tree structure of plugins/MyPlugin. Finally, all binary files of the plugin should be put inside that dedicated folder, and ASF will properly discover and use your plugin after restart.

Usually plugin developers will publish their plugins in form of a zip file with already-prepared structure for you, so it's enough to unpack that zip archive into plugins directory, which will create the appropriate folder automatically.

If the plugin was loaded successfully, you'll see its name and version in your log. You should consult your plugin developers in case of questions, issues or usage related to the plugins that you've decided to use.

You can find some featured plugins in our third-party section.

Please note that ASF plugins could be malicious. You should always ensure that you're using plugins made by developers that you can trust. ASF developers can no longer guarantee you usual ASF benefits (such as lack of malware or being VAC-free) if you decide to use any custom plugins. We're also unable to support setups that utilize custom plugins, since you're no longer running vanilla ASF code.

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For developers

Plugins are standard .NET libraries that inherit common IPlugin interface with ASF. You can develop plugins entirely independently of mainline ASF and reuse them in current and future ASF versions, as long as API remains compatible. Plugin system used in ASF is based on System.Composition, formerly known as Managed Extensibility Framework which allows ASF to discover and load your libraries during runtime.

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Getting started

Your project should be a standard .NET library targetting appropriate framework of your target ASF version, as specified in the compilation. We recommend you to target .NET Core, but .NET Framework plugins are also available.

The project must reference main ArchiSteamFarm assembly, either its prebuilt ArchiSteamFarm.dll library that you've downloaded as part of the release, or the source project (e.g. if you decided to add ASF tree as submodule). This will allow you to access and discover ASF structures, methods and properties, especially core IPlugin interface which you'll need to inherit from in the next step. The project must also reference System.Composition.AttributedModel at the minimum, which allows you to [Export] your IPlugin for ASF to use. In addition to that, you may want/need to reference other common libraries in order to interpret the data structures that are given to you in some interfaces, but unless you need them explicitly, that will be enough for now.

If you did everything properly, your csproj will be similar to below:

<Project Sdk="Microsoft.NET.Sdk">
  <PropertyGroup>
    <TargetFramework>net5.0</TargetFramework>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="System.Composition.AttributedModel" IncludeAssets="compile" Version="*" />
  </ItemGroup>

  <ItemGroup>
    <Reference Include="ArchiSteamFarm" HintPath="C:\\Path\To\Downloaded\ArchiSteamFarm.dll" />

    <!-- If building as part of ASF source tree, use this instead of <Reference> above -->
    <!-- <ProjectReference Include="C:\\Path\To\ArchiSteamFarm\ArchiSteamFarm.csproj" ExcludeAssets="all" Private="false" /> -->
  </ItemGroup>
</Project>

From the code side, your plugin class must inherit from IPlugin interface (either explicitly, or implicitly by inheriting from more specialized interface, such as IASF) and [Export(typeof(IPlugin))] in order to be recognized by ASF during runtime. The most bare example that achieves that would be the following:

using System;
using System.Composition;
using ArchiSteamFarm;
using ArchiSteamFarm.Plugins;

namespace YourNamespace.YourPluginName {
	[Export(typeof(IPlugin))]
	public sealed class YourPluginName : IPlugin {
		public string Name => nameof(YourPluginName);
		public Version Version => typeof(YourPluginName).Assembly.GetName().Version;

		public void OnLoaded() {
			ASF.ArchiLogger.LogGenericInfo("Meow");
		}
	}
}

In order to make use of your plugin, you must firstly compile it. You can do that either from your IDE, or from within the root directory of your project via a command:

# If your project is standalone (no need to define its name since it's the only one)
dotnet publish -c "Release" -o "out"

# If your project is part of ASF source tree (to avoid compiling unnecessary parts)
dotnet publish YourPluginName -c "Release" -o "out"

Afterwards, your plugin is ready for deployment. It's up to you how exactly you want to distribute and publish your plugin, but we recommend creating a zip archive with a single folder named YourNamespace.YourPluginName, inside which you'll put your compiled plugin together with its dependencies. This way user will simply need to unpack your zip archive into his plugins directory and do nothing else.

This is only the most basic scenario to get you started. We have ExamplePlugin project that shows you example interfaces and actions that you can do within your own plugin, including helpful comments. Feel free to take a look if you'd like to learn from a working code, or discover ArchiSteamFarm.Plugins namespace yourself and refer to the included documentation for all available options.

If instead of example plugins you'd want to learn from real projects, there is SteamTokenDumper plugin developed by us, which is bundled together with ASF. In addition to that, there are also plugins developed by other developers, in our third-party section.

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API availability

ASF, apart from what you have access to in the interfaces themselves, exposes to you a lot of its internal APIs that you can make use of, in order to extend the functionality. For example, if you'd like to send some kind of new request to Steam web, then you do not need to implement everything from scratch, especially dealing with all the issues we've had to deal with before you. Simply use our Bot.ArchiWebHandler which already exposes a lot of UrlWithSession() methods for you to use, handling all the lower-level stuff such as authentication, session refresh or web limiting for you. Likewise, for sending web requests outside of Steam platform, you could use standard .NET HttpClient class, but it's much better idea to use Bot.ArchiWebHandler.WebBrowser that is available for you, which once again offers you a helpful hand, for example in regards to retrying failed requests.

We have a very open policy in terms of our API availability, so if you'd like to make use of something that ASF code already includes, simply open an issue and explain in it your planned use case of our ASF's internal API. We most likely won't have anything against, as long as your use case makes sense. It's simply impossible for us to open everything that somebody would like to make use of, so we've opened what makes the most sense for us, and waiting for your requests in case you'd like to have access to something that isn't public yet. This also includes all suggestions in regards to new IPlugin interfaces that could make sense to be added in order to extend existing functionality.

In fact, internal ASF's API is the only real limitation in terms of what your plugin can do. Nothing is stopping you from e.g. including Discord.Net library in your application and creating a bridge between your Discord bot and ASF commands, since your plugin can also have dependencies on its own. The possibilities are endless, and we made our best to give you as much freedom and flexibility as possible within your plugin, so there are no artificial limits on anything, just us not being completely sure which ASF parts are crucial for your plugin development (which you can solve by letting us know, and even without that you can always reimplement the functionality that you need).

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API compatibility

It's important to emphasize that ASF is a consumer application and not a typical library with fixed API surface that you can depend on unconditionally. This means that you can't assume that your plugin once compiled will keep working with all future ASF releases regardless, it's just impossible if you want to keep developing the program further, and being unable to adapt to ever-ongoing Steam changes for the sake of backwards compatibility is just not appropriate for our case. This should be logical for you, but it's important to highlight that fact.

We'll do our best to keep public parts of ASF working and stable, but we'll not be afraid to break the compatibility if good enough reasons arise, following our deprecation policy in the process. This is especially important in regards to internal ASF structures that are exposed to you as part of ASF infrastructure, explained above (e.g. ArchiWebHandler) which could be improved (and therefore rewritten) as part of ASF enhancements in one of the future versions. We'll do our best to inform you appropriately in the changelogs, and include appropriate warnings during runtime about obsolete features. We do not intend to rewrite everything for the sake of rewriting it, so you can be fairly sure that the next minor ASF version won't just simply destroy your plugin entirely only because it has a higher version number, but keeping an eye on changelogs and occasional verification if everything works fine is a very good idea.

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Plugin dependencies

Your plugin will include at least two dependencies by default, ArchiSteamFarm reference for internal API, and PackageReference of System.Composition.AttributedModel that is required for being recognized as ASF plugin to begin with. In addition to that, it may include more dependencies in regards to what you've decided to do in your plugin (e.g. Discord.Net library if you've decided to integrate with Discord).

The output of your build will include your core YourPluginName.dll library, as well as all the dependencies that you've referenced. Since you're developing a plugin to already-working program, you don't have to, and even shouldn't include dependencies that ASF already includes, for example ArchiSteamFarm, SteamKit2 or Newtonsoft.Json. Stripping down your build off dependencies shared with ASF is not the absolute requirement for your plugin to work, but doing so will dramatically cut the memory footprint and the size of your plugin, together with increasing the performance, due to the fact that ASF will share its own dependencies with you, and will load only those libraries that it doesn't know about itself.

In general, it's a recommended practice to include only those libraries that ASF either doesn't include, or includes in the wrong/incompatible version. Examples of those would be obviously YourPluginName.dll, but for example also Discord.Net.dll if you decided to depend on it, as ASF doesn't include it itself. Bundling libraries that are shared with ASF can still make sense if you want to ensure API compatibility (e.g. being sure that Newtonsoft.Json which you depend on in your plugin will always be in version X and not the one that ASF ships with), but obviously doing that comes for a price of increased memory/size and worse performance, and therefore should be carefully evaluated.

If you know that the dependency which you need is included in ASF, you can mark it with IncludeAssets="compile" as we showed you in the example csproj above. This will tell the compiler to avoid publishing referenced library itself, as ASF already includes that one. Likewise, notice that we reference the ASF project with ExcludeAssets="all" Private="false" which works in a very similar way - telling the compiler to not produce any ASF files (as the user already has them). This applies only when referencing ASF project, since if you reference a dll library, then you're not producing ASF files as part of your plugin.

If you're confused about above statement and you don't know better, check which dll libraries are included in ASF-generic.zip package and ensure that your plugin includes only those that are not part of it yet. This will be only YourPluginName.dll for the most simple plugins. If you get any issues during runtime in regards to some libraries, include those affected libraries as well. If all else fails, you can always decide to bundle everything.

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Native dependencies

Native dependencies are generated as part of OS-specific builds, as there is no .NET Core runtime available on the host and ASF is running through its own .NET Core runtime that is bundled as part of OS-specific build. In order to minimize the build size, ASF trims its native dependencies to include only the code that can be possibly reached within the program, which effectively cuts the unused parts of the runtime. This can create a potential problem for you in regards to your plugin, if suddenly you find out yourself in a situation where your plugin depends on some .NET Core feature that isn't being used in ASF, and therefore OS-specific builds can't execute it properly, usually throwing System.MissingMethodException or System.Reflection.ReflectionTypeLoadException in the process.

This is never a problem with generic builds, because those are never dealing with native dependencies in the first place (as they have complete working runtime on the host, executing ASF). It's also automatically one solution to the problem, use your plugin in generic builds exclusively, but obviously that has its own downside of cutting your plugin from users that are running OS-specific builds of ASF. If you're wondering if your issue is related to native dependencies, you can also use this method for verification, load your plugin in ASF generic build and see if it works. If it does, you have plugin dependencies covered, and it's the native dependencies causing issues.

Unfortunately, we had to make a hard choice between publishing whole runtime as part of our OS-specific builds, and deciding to cut it out of unused features, making the build over 50 MB smaller compared to the full one. We've picked the second option, and it's unfortunately impossible for you to include the missing runtime features together with your plugin. If your project requires access to runtime features that are left out, you have to include full .NET runtime that you depend on, and that means running your plugin together with generic ASF flavour. You can't run your plugin in OS-specific builds, as those builds are simply missing a runtime feature that you need, and .NET Core runtime as of now is unable to "merge" native dependency that you could've provided with our own. Perhaps it'll improve one day in the future, but as of now it's simply not possible.

ASF's OS-specific builds include the bare minimum of additional functionality which is required to run our official plugins. Apart of that being possible, this also slightly extends the surface to extra dependencies required for the most basic plugins. Therefore not all plugins will need to worry about native dependencies to begin with - only those that go beyond what ASF and our official plugins directly need. This is done as an extra, since if we need to include additional native dependencies ourselves for our own use cases anyway, we can as well ship them directly with ASF, making them available, and therefore easier to cover, also for you.