Event Mapper Connector
The event mapper connector provides a mechanism to translate events that signify changes to metadata from a third party metadata repository into events that are send out to other cohort members. It is paired with a repository-connector and is able to call it to retrieve and maintain metadata in the third party metadata repository. During its initialization, it is passed an event processor that is responsible for distributing events from the event mapper to the other members of connected cohorts.
The event mapper for a third party metadata repository is shown running in a repository proxy server. It is listening for events from the third party metadata repository, using the repository connector to retrieve and update metadata in its own third party metadata repository in order to formulate equivalent events for the open metadata ecosystem. These are published through the event processor supplied during its initialization.
Event mappers are needed in a repository proxy server if the third party technology that it is integrating into the open metadata repository cohort also has its own mechanisms for maintaining metadata. If the third party metadata repository's contents are static, or only updated through Egeria's mechanisms then no event mapper is needed. If no event mapper is present, then the repository proxy ignores refresh event requests from other members of the connected cohorts. This means its metadata is only available through federated queries.
Since each event mapper is tied to a third party technology, core Egeria does not supply any implementations of this connector. There is, however, the following implementation available: