This JIRA describes a proposal for standard types for open metadata entities and relationships. For example, glossaries, database definitions, rules, policies, ...
The value of having standard definitions for metadata is to enable type safe APIs and business level UIs plus be able to exchange metadata between different instances of metadata repositories.
The implementation of these common types is divided into 8 areas:
- Area 0 - for extensions to Apache Atlas's base model
- Area 1 - for definitions of the data-related assets we are governing and using
- Area 2 - for a glossary of meanings and semantic relationships
- Area 3 - for information about asset use, crowd-sourced definitions and collaboration around the data-related assets
- Area 4 - for governance such as policies, rules and classifications
- Area 5 - for reference models and reference data
- Area 6 - for metadata discovery processes (see https://issues.apache.org/jira/browse/ATLAS-1748)
- Area 7 - for lineage
Adaptation and flexibility are key in metadata environments so these common definitions must be extensible - and we still need to support the ad hoc definition of new types in Atlas.
Apache Atlas supports meta-types that are used in the definition of new types. These are currently enumeration, struct, classification and entity. JIRA https://issues.apache.org/jira/browse/ATLAS-1690 adds relationships to this list. The open metadata models make use of all of these meta-types. These are represented by sterotypes on the classes of the open metadata definitions.
The Atlas wiki has the models as a set of linked pages which are probably the easiest way to view the models.
Start here: https://cwiki.apache.org/confluence/display/ATLAS/Building+out+the+Apache+Atlas+Typesystem