# Plugins > Extend DS Server with .NET plugins that add controllers, middleware and services: IPlugin, how the Plugins folder is loaded, package versions and security. - **Product:** DS Server - **Section:** Documentation - **Kind:** Topic - **Path:** DS Server > Plugins - **1117 words** - **Web URL:** https://docs.textcontrol.com/ds-server/plugins/ - **LLMs URL:** https://docs.textcontrol.com/ds-server/plugins/llms.txt - **LLMs-Full URL:** https://docs.textcontrol.com/ds-server/plugins/llms-full.txt --- Plugins let you add your own code to DS Server instead of running it in a separate application beside the server: an endpoint of your own, a step in the request pipeline, a service that uses the document processing of DS Server. .NET developers who extend a DS Server installation find out here how plugins fit into the server, how to build and deploy one, which DS Server services a plugin can use, and how a plugin receives the documents signed in the Document Viewer. ### What a Plugin Is A plugin is a .NET class library, compiled into a *.dll*, that DS Server loads when it starts. It contains a public class that implements the `IPlugin` interface of the NuGet package `TXTextControl.DocumentServices.Plugin.Abstractions`. Through this interface, a plugin can: - **Add endpoints.** Its ASP.NET Core API controllers answer under the address of DS Server, for example at `/plugin/hello`. - **Add middleware and route handlers** to the request pipeline of DS Server, for logging or metrics. - **Register services** in the dependency injection container of DS Server, and read the configuration of DS Server, including its *appsettings.json* file. - **Run code** when DS Server starts and when the plugin is unloaded. - **Use DS Server's services.** Since version 5.0, `IDocumentProcessingService` gives a plugin the conversion, mail merge, PDF and barcode features of DS Server, and `IDocumentEditorSessionService` the documents open in the Document Editor. - **Link a page** from the **Plugins** page of the admin portal. Plugins are available since DS Server 4.1.0, released in September 2025. The services followed with DS Server 5.0.0. ### How DS Server Loads Plugins Each plugin has its own subfolder in the *Plugins* folder of the DS Server installation, together with the assemblies it depends on: ```text DS Server folder/ ├── TXTextControl.DocumentServices.dll ├── appsettings.json └── Plugins/ ├── README.md ├── MyFirstPlugin/ │ └── MyFirstPlugin.dll └── SigningPlugin/ └── SigningPlugin.dll ``` When DS Server starts, it searches the subfolders for classes that implement `IPlugin` and loads them. Its console output lists each plugin with the name and version the plugin reports: ```text Loading plugins from '/opt/dsserver/Plugins'... Loaded plugin: MyFirstPlugin (v1.0.0) ``` A plugin that is added or updated takes effect only after DS Server is restarted. The **Plugins** page of the admin portal lists the loaded plugins with their name, version and description and whether each one is enabled. > Warning > > **Plugin Endpoints and OAuth.** The endpoints of a plugin run in the same process as DS Server and use its address and port, but they are not covered by its OAuth protection. A plugin protects its own endpoints, with the access token validation of DS Server described in [Creating a Plugin](https://docs.textcontrol.com/ds-server/plugins/creating/#protect-the-endpoint-with-oauth). ### Versions | DS Server | Package `TXTextControl.DocumentServices.Plugin.Abstractions` | What a plugin can use | |---|---|---| | 4.1.0 | 4.1.0, for .NET 8 | `IPlugin` and `PluginContext` | | 5.0.0 and later | 5.0.0 or 5.0.1, for .NET 8 and .NET 10 | In addition, `IDocumentProcessingService`, `IDocumentEditorSessionService` and the constant `PluginContext.AuthenticationScheme` | DS Server 5.0 is built with .NET 10, and the official sample plugin targets `net10.0`. The package and its types are documented in the reference: [Plugin.Abstractions](https://docs.textcontrol.com/ds-server/reference/dotnet-api/txtextcontrol-documentservices-plugin-abstractions/llms-full.txt). ### Find the Right Page | If you want to | Read | |---|---| | Build, deploy and test a first plugin | [Creating a Plugin](https://docs.textcontrol.com/ds-server/plugins/creating/llms-full.txt) | | Protect a plugin endpoint with an access token | [Creating a Plugin](https://docs.textcontrol.com/ds-server/plugins/creating/#protect-the-endpoint-with-oauth) | | Convert or merge documents in a plugin | [Plugin Services](https://docs.textcontrol.com/ds-server/plugins/services/llms-full.txt) | | Change the document a user has open in the Document Editor | [Plugin Services](https://docs.textcontrol.com/ds-server/plugins/services/#idocumenteditorsessionservice) | | Receive the documents signed in the Document Viewer | [Custom Signing Endpoints](https://docs.textcontrol.com/ds-server/plugins/signing/llms-full.txt) | ### Where to Start 1. Build *MyFirstPlugin* in [Creating a Plugin](https://docs.textcontrol.com/ds-server/plugins/creating/llms-full.txt). It shows every step once: the project, the interface, the deployment, the log and the test. 2. Add the services you need from [Plugin Services](https://docs.textcontrol.com/ds-server/plugins/services/llms-full.txt). 3. For signing workflows, continue with [Custom Signing Endpoints](https://docs.textcontrol.com/ds-server/plugins/signing/llms-full.txt). ### Pages in This Section - [Creating a Plugin](https://docs.textcontrol.com/ds-server/plugins/creating/llms-full.txt): create a class library, implement `IPlugin`, deploy it into the *Plugins* folder and protect its endpoint. - [Plugin Services](https://docs.textcontrol.com/ds-server/plugins/services/llms-full.txt): use `IDocumentProcessingService` and `IDocumentEditorSessionService` in plugin controllers. - [Custom Signing Endpoints](https://docs.textcontrol.com/ds-server/plugins/signing/llms-full.txt): receive signed documents from the Document Viewer in a plugin endpoint protected by an access token. --- ## In This Section - [Creating a Plugin](https://docs.textcontrol.com/ds-server/plugins/creating/llms-full.txt): Build a DS Server plugin step by step: a .NET class library with IPlugin, a controller, middleware and settings, deployment, testing and OAuth protection. - [Plugin Services](https://docs.textcontrol.com/ds-server/plugins/services/llms-full.txt): Merge, convert and inspect documents in a DS Server plugin with IDocumentProcessingService, and load or save editor sessions with IDocumentEditorSessionService. - [Custom Signing Endpoints](https://docs.textcontrol.com/ds-server/plugins/signing/llms-full.txt): Receive documents signed in the Document Viewer in a DS Server plugin endpoint: SignatureData, RedirectUrlAfterSignature, access token checks and PDF storage. --- ## Nearby - **Previous:** [Errors and Status Codes](https://docs.textcontrol.com/ds-server/document-processing/errors/llms-full.txt) - **Next:** [Creating a Plugin](https://docs.textcontrol.com/ds-server/plugins/creating/llms-full.txt)