Exceptions | message-bus | Webware Documentation

All exceptions live under Webware\MessageBus\Exception.

Exception Extends / Implements Thrown when

Exception	Extends / Implements	Thrown when
`InvalidConfigurationException`	`InvalidArgumentException`	Configuration is missing or malformed, a message has no `command_map`/`query_map` entry, or a resolved handler service is not an instance of the expected handler marker (`MessageHandlerResolver`, `MiddlewarePipeFactory`, `collection_mapper_factory`).
`ServiceNotFoundException`	`RuntimeException`, `Psr\Container\NotFoundExceptionInterface`	A required service (`config`, a mapped handler, or `MiddlewarePipelineInterface`) isn't registered in the container (`MessageHandlerResolver`, `Container\MessageBusFactory`, `Container\MiddlewarePipeFactory`).
`HandlerMethodNotFoundException`	`InvalidArgumentException`	The resolved handler has no callable method for the strategy's method name (`MessageHandlerMiddleware`).
`MessageException`	`RuntimeException`	The pipeline reaches `Handler\EmptyPipelineHandler` without ever producing a `ResultInterface`.
`NextHandlerAlreadyCalledException`	`DomainException`	`Next::handle()` is invoked more than once on the same instance.

InvalidConfigurationException

InvalidArgumentException

Configuration is missing or malformed, a message has no command_map/query_map entry, or a resolved handler service is not an instance of the expected handler marker (MessageHandlerResolver, MiddlewarePipeFactory, collection_mapper_factory).

ServiceNotFoundException

RuntimeException, Psr\Container\NotFoundExceptionInterface

A required service (config, a mapped handler, or MiddlewarePipelineInterface) isn't registered in the container (MessageHandlerResolver, Container\MessageBusFactory, Container\MiddlewarePipeFactory).

HandlerMethodNotFoundException

InvalidArgumentException

The resolved handler has no callable method for the strategy's method name (MessageHandlerMiddleware).

MessageException

RuntimeException

The pipeline reaches Handler\EmptyPipelineHandler without ever producing a ResultInterface.

NextHandlerAlreadyCalledException

DomainException

Next::handle() is invoked more than once on the same instance.

Each exception exposes named static constructors (for example ServiceNotFoundException::fromService(), HandlerMethodNotFoundException::forMethod(), InvalidConfigurationException::fromUnMappedMessage()) rather than public constructors, keeping error messages consistent at every call site.