abp/docs/en/Features.md

Features

ABP Feature system is used to enable, disable or change the behavior of the application features on runtime.

Feature system was originally designed to control the tenant features in a multi-tenant application. However, it is extensible and capable of determining features by any condition.

The feature system is implemented with the Volo.Abp.Features NuGet package. Most of the times you don't need to manually install it since it comes pre-installed with the application startup template.

Checking for the Features

Before starting to explain how to define features, let's see how to check a feature in your application code.

RequiresFeature Attribute

[RequiresFeature] attribute (defined in the Volo.Abp.Features namespace) is used to declaratively check if a feature is enabled or not.

Example: Check if the current user/tenant has "PDF Reporting" feature enabled

public class ReportingAppService : ApplicationService, IReportingAppService
{
    public async Task<CsvReportResultDto> GetCsvReportAsync()
    {
        throw new System.NotImplementedException();
    }

    [RequiresFeature("MyApp.PdfReporting")]
    public async Task<PdfReportResultDto> GetPdfReportAsync()
    {
        throw new System.NotImplementedException();
    }
}

• RequiresFeature(...) simply gets a feature name to check if it is enabled or not. If not enabled, an authorization exception is thrown and a proper response is returned to the client side.
• [RequiresFeature] can be used for a method or a class. When you use it for a class, all the
• RequiresFeature may get multiple feature names, like [RequiresFeature("Feature1", "Feature2")]. In this case ABP checks if current user/tenant has any of the features enabled. Use [RequiresFeature("Feature1", "Feature2", RequiresAll = true)] to force to allow only if all of the features are enabled.
• Multiple usage of [RequiresFeature] attribute is enabled, so it checks all of them.

About the Interception

ABP Framework uses the interception system to make the [RequiresFeature] attribute working. So, it can work with any class that is injected from the dependency injection.

However, there are some rules should be followed in order to make it working;

• If you are not injecting the service over an interface (like IMyService), then the methods of the service must be virtual (otherwise, dynamic proxy / interception system can not work).
• Only async methods (methods returning a Task or Task<T>) are intercepted.