Re: Sharing binaries/code between client and server in a DDD environment

Hi,


I agree with Paul. I have used this practice of a "published domain" quite
alot. Some years ago I wrote a post on this and other aspects of the
architecture we are using:
http://se-thinking.blogspot.se/2012/09/ddd-on-top-of-services-ddd-inside.html
See second last section in the post.


Regards,

Jörgen
Den 22 maj 2014 18:46 skrev "Paul Rayner
[email protected][domaindrivendesign]" <
[email protected]>:


>
>
> The objects you've defined below seem to be functioning more as data
> transfer objects (DTOs) rather than value objects. Especially since you
> have them as part of your service layer, which is outside of the domain
> model, if I am understanding you correctly.
>
> If they are, in-fact, value objects in your domain model, they should be
> immutable and I would recommend you implement everything that flows out of
> that choice. In that case, I have no issues sharing them, so long as you
> adhere to the guidelines for shared kernel:
> https://domainlanguage.com/ddd/patterns/DDD_Reference_2011-01-31.pdf.
>
> Cheers,
> Paul.
>
> On Thu, May 22, 2014 at 8:18 AM, Alastair van Leeuwen
> [email protected] [domaindrivendesign] <
> [email protected]> wrote:
>
>>
>>
>> Hi,
>>
>> How appropriate is it when sharing binaries or code between a client and
>> a server in a DDD environment.
>> I by no means advocate sharing the entire Model but just certain common
>> aspects.
>>
>> For example, when using C# with WCF, it is accepted if the service
>> interfaces are shared between the client and the server.
>> What if this is taken one step further?
>>
>> For example:
>> interface ICustomerMaintenance
>> {
>>  void CreateCustomer(string Name, string Surname, Sex sex, PhoneNumber
>> mobileNumber, PhoneNumber landNumber, ...);
>> }
>>
>> Sex is defined as:
>>     enum Sex
>>     {
>>         Male, Female
>>     }
>>
>> PhoneNumber is a value object defining a phone number.
>>
>> Although Sex and PhoneNumber are both Value Objects, can they not be
>> defined in some common area and shared?
>> It seems like extra complexity if these value objects must be re-created
>> on the client side.
>>
>> When sharing these domain concepts in both the client and server, is
>> there a special name for it?
>> Is it a Shared Kernel or is this term used only when integrating between
>> Bounded Context?
>>
>> There are already common value objects available in C#, such as DateTime.
>> If a DateTime did not exist in C#, surely it does not have to be
>> re-created on the client and server?
>>
>> Kind regards,
>> Alastair
>>
>>
>>
>>
>>
>>
>  
>