CHR0054: Reactor method has an unsupported return type

Rule description

A reactor method whose first parameter is an [EventType] but whose synchronous return type is not one of the supported shapes is skipped during handler discovery. CHR0054 reports that return type, rather than treating it as an unresolvable parameter.

Severity

Warning

Supported returns

• void or Task.
• A registered event type, EventForEventSourceId, or EventsWithConcurrencyScopes.
• IEnumerable<T> where T is a registered event type, EventForEventSourceId, or object (for mixed events and targeted events).
• Task<T> for any side effect that a registered reactor side-effect handler can process, including the shapes above.

A synchronous custom side-effect type cannot be discovered as a reactor handler. Return it from Task<T> instead and register an IReactorSideEffectHandler that can handle its value.

Related rules

• CHR0004: Reactor method has a parameter that cannot be resolved.
• CHR0005: Reactor event parameter must have [EventType] attribute.