In a nut shell, with CQRS you have Commands that will change the state of your application and Queries that will return information about the state of your application.
Installation
composerrequiresonsofphp/cqrs-contract
Messages
Both Commands and Queries are considered Messages and are handled by Message Handlers.
Message Handlers
When a message is dispatched/handled, it is handled by a message handler.
Message Bus
The Message Bus is given a Message and will use a Message Handler to handle the message. If it's a Query Message, the bus will return a result and for Command Messages, it will not return anything.
Message Handler Provider
Returns the Handler that will handle the Message. They do not actually handle or process the message.
