Posts tagged metadata services
It has been almost a year since my last post about the metadata services. I talked about how-to set up a File-based MDS and DB-based MDS. This post talks about the usage of the files, placed in the MDS, in the different components available in a SOA composite. If the MDS is a new thing for you then I advise to read my previous about this subject first.
You can spot the presence of a file that is a reference to the MDS if it uses the oramds: URI annotation. Files are no longer referenced to a hardcoded or relative file path.
To start using you’re MDS that you have set up we will create a new SOA application. Let call the application WorkflowSOAapp and create a SOA project and call it WebformService.
Before I talk about the advantages en methods of using the MDS, I want to introduce myself, because this is my first public post on the AMIS technology blog. My name is Robert van Mölken and I’m 26 years old. I’m now actively working, as a SOA Consultant / Developer, for nearly 5 years. My main toolstack is SOA Suite (3,5 years 10gR3 and 1,5 years 11gR1), but also have experience with opensource BPEL / ESB alternatives from Apache.
In many big SOA application all the composites use the same canonical1 data model (message definitions) for their service contracts. Many entities and elements (complex- and simple types) are reused. Therefor it is not a good choice to use a local copy for the service contracts (WSDLs) and message definition files (XSDs) in each SOA composite project.
If you do so and a mayor (common) part of the message definitions changes then you need to update all the SOA composite projects, where these files are used, with the new version of the files. Oracle created the MDS to solve this issue. MDS stands for MetaData Services. The MDS holds all kind of xml-based files, like WSDLs, XSDs, Domain Values Maps but can also hold fault policies and event definitions More >