🚃 Golang MediatR
This package is a Mediator Pattern implementation in golang, and inspired by great jbogard/mediatr library in .Net.
For decoupling some objects in a system we could use Mediator object as an interface, for decrease coupling between the objects. Mostly I uses this pattern when I use CQRS in my system.
Registering Handlers
// Command
type CreateProductCommand struct {
ProductID uuid.UUID `validate:"required"`
Name string `validate:"required,gte=0,lte=255"`
Description string `validate:"required,gte=0,lte=5000"`
Price float64 `validate:"required,gte=0"`
CreatedAt time.Time `validate:"required"`
}
// Command Handler
type CreateProductCommandHandler struct {
productRepository *repository.InMemoryProductRepository
}
func NewCreateProductCommandHandler(productRepository *repository.InMemoryProductRepository) *CreateProductCommandHandler {
return &CreateProductCommandHandler{productRepository: productRepository}
}
func (c *CreateProductCommandHandler) Handle(ctx context.Context, command *CreateProductCommand) (*creating_product_dtos.CreateProductResponseDto, error) {
product := &models.Product{
ProductID: command.ProductID,
Name: command.Name,
Description: command.Description,
Price: command.Price,
CreatedAt: command.CreatedAt,
}
createdProduct, err := c.productRepository.CreateProduct(ctx, product)
if err != nil {
return nil, err
}
response := &creating_product_dtos.CreateProductResponseDto{ProductID: createdProduct.ProductID}
return response, nil
}
// Registering Command Handler to the mediatr
mediatr.RegisterHandler[*creating_product.CreateProduct, *creating_products_dtos.CreateProductResponseDto](createProductCommandHandler)
Sending Request
// Sending command to mediatr for routing to the corresponding command handler
command := creating_product.NewCreateProductCommand(request.Name, request.Description, request.Price)
mediatr.Send[*creating_products_dtos.CreateProductResponseDto](ctx.Request().Context(), command)
Using Pipeline Behaviors
TODO
