# LS2007: Reaction or Job Name Hides Its Kind

## Intent

LS2007 is a compiler check that reports a reaction, the type that answers a domain event, or a scheduled job whose name does not say which of the two it is, so the model builder cannot discover it by name. This page states what the rule reports, where the error sits, and how to name the reaction or job for its kind.

## Reference

### What the Rule Enforces

LS2007 enforces [Use architectural suffixes](https://litespec.dev/2.0.0/workspace/naming.md#use-architectural-suffixes) (`litespec/workspace/naming#use-architectural-suffixes`). It runs in Application and Infrastructure. Its category is `LiteSpec.Layers`. It reports an error and is enabled by default, as the [Analyzers overview](https://litespec.dev/2.0.0/analyzers/README.md) describes.

### What the Rule Reports

The rule reports a class that implements an interface named `IEventHandler` or `IDomainEventReaction` unless its name ends in `Reaction` or matches `{Action}On{PastFact}Handler`, with an action before `On` and a fact between `On` and `Handler`. The rule reports a class that derives from `BackgroundService` or implements `IHostedService` unless its name ends in `Job` or `Worker`, or contains `Recurring`. The diagnostic sits on the type name, and its message names the kind and the accepted shape.

### Failing Example

```csharp
internal sealed class SubscriberNotifier : IEventHandler<OrderPlacedEvent>
{
}

internal sealed class ReminderLoop : BackgroundService
{
}
```

### Passing Example

```csharp
internal sealed class NotifySubscribersOnOrderPlacedHandler : IEventHandler<OrderPlacedEvent>
{
}

internal sealed class ReminderJob : BackgroundService
{
}
```

### How to Fix

Name a reaction `{Action}On{PastFact}Handler` or end it in `Reaction`, and name a job to end in `Job` or `Worker`, or to contain `Recurring`.

## Notes

### What the Rule Ignores

The rule does not report a class that is neither a reaction nor a job, and it does not report interfaces. A class that is both a reaction and a job is checked against both shapes. It does not run in Domain, Application.Abstractions, or WebApi.