How to send commands using ServiceStack?

Question

I am just getting into REST and ServiceStack and for now my GETs are returning strings which could be XML or Json.

I now need to work on the PUT or POST commands which change my domain model.

For a single resource, I could have a number of commands on my domain model (i.e for a customer resource I could have change name, change address, change billing address, etc). Each change to the domain model will consist of only one of these changes (not all).

With ServiceStack do I create ONE DTO which contains a flag/enumeration to indicate what the change is? This means I have one REST service with a case statement to indicate what I should do on the domain. This also means I have a very large DTO object which contains the data that needs to be posted to change my domain (of which a lot of the properties will be empty).

Or do I create lots of DTOs and REST services, each specific to the change on my model? In this case would I need to add ?Command=changeAddress to the URL? Not sure if this is right.

Answer 1

This also means I have a very large DTO object which contains the data that needs to be posted to change my domain (of which a lot of the properties will be empty).

A very large DTO object with empty properties is not a performance issue since ServiceStack's text serializers (i.e. JSON/JSV) only emit data for non-null values and doesn't spend time de-serializing what's not in the payload - so it shouldn't be a concern from a performance perspective.

Other than requiring the same Request DTO to be used for each of your REST Service Verbs - there is no "ServiceStack way" on how to design your services and ServiceStack doesn't force a design-style.

If you want to prefer a more REST-ful design, you would split up your customer into manageable entities that can be modified separately, e.g to change a customers Billing address I would do something like:

PUT /customers/address/billing
{
    "Line1": "123 Street",
    "City": "Brooklyn",
    "State": "NY"
}

And have a separate REST service to manage customer addresses, e.g:

Register<CustomerAddress>("/customers/address/{AddressType}");