query

type Answer ¶

type Answer interface{}

Answer is a marker interface for answers to Domain Queries, returned by a Query Handler.

type Dispatcher ¶

type Dispatcher interface {
	Dispatch(context.Context, Query) (Answer, error)
}

Dispatcher represents a component that routes Domain Queries into their appropriate Query Handlers.

Differently from Command Handlers, Query Handlers return an Answer to the Domain Query dispatched, which usually is the Domain Read Model for a specific query type.

Implementations can be synchronous or asynchronous, although it is generally used as a synchronous component, i.e. the call to Dispatch returns when the query has been resolved.

type Handler ¶

type Handler interface {
	QueryType() Query
	Handle(context.Context, Query) (Answer, error)
}

Handler is a component capable of handling Domain Queries, resolving them into an Answer, typically a Domain Read Model.

An Handler implementation specifies their supported Query type using the QueryType method. Please, make sure the type returned by this method reflects the same type of the Query submitted in your application.

type Query ¶

type Query interface{}

Query is a marker interface for Domain Query types.

type SimpleBus ¶

type SimpleBus struct {
	// contains filtered or unexported fields
}

SimpleBus is a simple Query Bus implementation, synchronous and that works in-memory by registering Query Handlers and dispatching Domain Queries, the Bus will take care of routing the Query to the appropriate Query Handler.

Use NewSimpleBus to create a new SimpleBus instance.

func NewSimpleBus() *SimpleBus

func (b SimpleBus) Dispatch(ctx context.Context, query Query) (Answer, error)

func (b *SimpleBus) Register(handler Handler)