Re: Bounded Roles

[MarcoP]

do your bounded roles act as your application layer?

[Giacomo Tesio]

Hi Marco,

no, not exactly, at least if I understand what you mean for application layer.

Consider however that for "application layer" my mind read the ISO/OSI application layer in TCP/IP (that is unrelated to this... :-D).

Bounded roles act as entry points and junction points between the domain model (simple plain old clr objects behind pure interfaces) and the environment running it.

They can access, instantiate and return repositories and services but they are not an application layer.

As most domain objects (and bounded roles too) are behind pure interfaces, such interfaces define a layer: everything that need to USE the domain (eg the GUI) works with such interfaces.

However many things can be more complex, since entities and services could be proxied to inject infrastructural aspect like persistence and logging.

Thus "bounded role" is a term that has two definition in two different context:

- from the domain's client's developer point of view they are pure interface that strongly type the context boundaries (and this definition is valid for the modeler too);

- for the dbas, architects and developers facing with acls, persistence, logging, threading, syncronization of the instances and so on, bounded roles are a junction point between the infrastracture (persistence, logging, locking, caching) and the pure domain objects.

Hope this helps.

Giacomo

[MarcoP]

Yep, makes sense. My understanding of an application is where the use
case scenarios and infrastructure concerns are coordinated and it
sounds the bounded roles play this part. I saw one of your posts on
the ddd message board you are giving a talk soon. will that be
recorded and transcribed in english by chance?

[Giacomo Tesio]

For sure I will translate the slides...

Moreover I hope to record the talk and share it on vimeo/youtube.

Giacomo

[Marco Paul]

great, looking forward to it. when is your talk?