dotnet:add-error-mapping

Context

Creates a new domain error type and registers it in the error mapping configuration, following the Result pattern used in the project.

Inputs

$ARGUMENTS - Error name, HTTP status code, and description (e.g., "OrderNotFound 404 Order was not found")

Steps

1. Parse Arguments

Extract:

• •Error name (e.g., OrderNotFound → OrderNotFoundError)
• •HTTP status code (e.g., 404)
• •Description (e.g., "Order was not found")

2. Read Standards

Read standards/dotnet.md for error mapping patterns.

3. Create Error Class

public class {Name}Error : IResultError
{
    public string Message { get; }

    public {Name}Error(string message = "{description}")
    {
        Message = message;
    }
}

4. Register Error Mapping

Add to error mapping configuration:

mappings.Map<{Name}Error>()
    .To<ProblemDetails>(StatusCodes.Status{Code})
    .WithMapping((error, problemDetails) =>
    {
        problemDetails.Title = "{Human-readable title}";
        problemDetails.Detail = error.Message;
    });

5. Verify

• •Run dotnet build to confirm compilation.
• •Check that the error type is used correctly in existing Result returns.

Verification

• •Error class follows IResultError pattern
• •Mapping registered with correct HTTP status code
• •ProblemDetails format matches RFC 7807
• •Build passes