Hi All,
right now we are developing our first eSOA Composite Application with CE and I have some questions regarding Business Objects, the import of external services and the development of application services.
As I understood there are two ways to provide business functionality for composite applications:
a. Import backend functionality as an external service (e.g. BAPI, RFC) at the CAF, build the application service which can be used as a callable object for UIs or the GPs
b. Develop a local Business Object (in CAF) providing the business logic, create the application service which again can be used as a callable object. Furthermore the application service can be exposed as a Web Service (external service).
My questions:
1. When is it appropriate to to import external services in stead of developing local BOs?
2. Under what conditions is it advisable to (solely) develop local BOs?
3. What are the advantages / disadvantages regarding the reusability of the services (in option a and b)?
Note: We are developing on NetWeaver 2004s.
Please let me know, if you need more information to answer the questions!
Thanks for your advice in advance,
Regards,
Ivonne
Hi Ivonne,
first of all, the CAF Business Objects (BOs) itself don't contain any business logic, they're basically just local database tables (with some CRUD services on top).
Business logic is implemented in Application Services (AS).
Now, regarding local BO's vs. external services, it depends on your use case. If the data is already available somewhere in your backend system it makes sense to use external services. For instance you wouldn't want to store business partners all over different composites. For data that is specific to your composite (in particular configuration, customizing etc.) and not likely to be reused by other applications you should use local BOs.
Accessing local BO's is also much faster than calling external services.
You can do reuse in both scenarios, since the CAF services can be exposed as web services.
Regards,
Christian
Edited by: Christian Loos on Apr 8, 2008 6:11 PM
Add a comment