Processing of Resources in the Registry

To use the Governance Registry efficiently, it is useful to have a basic understanding on how resources and related operations are handled in the Registry.

The diagram below illustrates a simplified form on the WSO2 Registry architecture.

Web and APP interfaces are mechanisms used to expose the Registry functionality, in a servlet deployment.

Embedded Registry exposes all its functionalities via two main interfaces.

The Registry API - Provides all resource related operations.
The User Manager API - Exposes user/role and authorization features.

The Registry API has methods for all basic resource operations such as get(...), put(...), delete(...), as well as methods for other resource related operations such as accessing associations, versioning, etc.

Repository component manages the actual storage of resources and the VersionRepository component handles all versioning related functionalities.

Data access layer executes SQL statements to interact with the database for the purpose of performing various Registry operations.

Having a general understanding of key Registry components, let's see what takes place when a Registry API method is invoked.

If a method that directly relates to a resource is invoked, the Registry delegates it to the Repository after performing certain housekeeping tasks related to transactions, session management and logging.

The Repository performs its operations interacting with the data access layer to perform low-level database operations.

Once the Repository completes its operations, the Registry invokes the VersionRepository if the resource requires versioning. Similar to the Repository, all versioning operations will be taken over by the VersionRepository.

What concerns the process of handling operations, they do not directly relate to resources. Such operations include commenting, tagging, associations, etc. As these operations are not related to resources, there is no need to call the Repository or VersionRepository components. The Registry directly accesses its data access layer, after performing typical housekeeping tasks that relates to such operations.