modulus add-command

Scaffolds a CQRS command with its handler and FluentValidation validator inside a module's Application layer. Commands represent intent to change state and are dispatched through the Modulus mediator pipeline.

Synopsis

modulus add-command <command-name> [options]

Arguments

Argument	Description
<command-name>	PascalCase name for the command (e.g., CreateProduct, PlaceOrder).

Options

Option	Description	Default
--module, -m <name>	(Required) Target module where the command will be created.	--
--solution, -s <path>	Path to the .slnx solution file.	Auto-discovered
--result-type, -r <type>	Return type wrapped in Result<T>. Omit for a void Result (commands that return no value).	Void Result

Generated Output

Running modulus add-command CreateProduct --module Catalog --result-type Guid generates three files:

Command record

src/Modules/Catalog/EShop.Modules.Catalog.Application/Commands/CreateProduct/CreateProductCommand.cs

using EShop.SharedKernel.Application;

namespace EShop.Modules.Catalog.Application.Commands.CreateProduct;

public sealed record CreateProductCommand : ICommand<Guid>;

Handler class

src/Modules/Catalog/EShop.Modules.Catalog.Application/Commands/CreateProduct/CreateProductCommandHandler.cs

using EShop.SharedKernel.Application;

namespace EShop.Modules.Catalog.Application.Commands.CreateProduct;

public sealed class CreateProductCommandHandler
    : ICommandHandler<CreateProductCommand, Guid>
{
    public async Task<Result<Guid>> Handle(
        CreateProductCommand command,
        CancellationToken cancellationToken)
    {
        // TODO: Implement command logic
        throw new NotImplementedException();
    }
}

Validator class

src/Modules/Catalog/EShop.Modules.Catalog.Application/Commands/CreateProduct/CreateProductCommandValidator.cs

using FluentValidation;

namespace EShop.Modules.Catalog.Application.Commands.CreateProduct;

public sealed class CreateProductCommandValidator
    : AbstractValidator<CreateProductCommand>
{
    public CreateProductCommandValidator()
    {
        // TODO: Add validation rules
    }
}

When --result-type is omitted, the command implements ICommand (no generic parameter) and the handler returns Result instead of Result<T>.

Examples

Create a command that returns a Guid:

modulus add-command CreateProduct --module Catalog --result-type Guid

Create a void command (no return value):

modulus add-command DeleteProduct --module Catalog

Create a command that returns a custom type:

modulus add-command PlaceOrder --module Orders --result-type OrderConfirmation

See Also

• modulus add-query -- Scaffold read-side queries
• modulus add-endpoint -- Wire commands to HTTP endpoints
• Commands & Queries -- How the mediator dispatches commands
• Pipeline Behaviors -- Validation, logging, and other cross-cutting concerns