CEDAR 2.9.0 Release
CEDAR 2.9.0 has been deployed to production. This release makes YAML a first-class representation across the artifact API and modernizes the platform's dependency and testing foundations.
What's New
First-class YAML support. CEDAR now reads and writes YAML for templates, elements, fields, and instances. Earlier versions could serve an artifact as YAML on download but accepted only JSON on the way in; you can now create and update artifacts by submitting YAML directly. The API negotiates the representation per request — send Accept: application/yaml to receive YAML, or Content-Type: application/yaml to submit it — so JSON and YAML clients use the same endpoints interchangeably.
The YAML forms and examples are documented in the CEDAR YAML specification: https://metadatacenter.readthedocs.io/en/latest/yaml-spec/. The JSON API is browsable in the interactive API reference: https://resource.metadatacenter.org/api/
Maintenance and Modernization
A round of platform maintenance landed in this release, with no change to the public API beyond the YAML additions above:
- Migrated the microservices to Dropwizard 4 / Jakarta EE 9 (javax → jakarta, Jetty 11, Jersey 3).
- Upgraded core client libraries: HttpClient 4 → 5, Jedis 2.9 → 5.x, Swagger-core v3 / OpenAPI 3, and the JSON Schema validator (FGE → networknt).
- Moved the MySQL driver to the maintained
com.mysql:mysql-connector-jcoordinate and refreshed a batch of parent-POM dependency versions. - Regenerated and now serve OpenAPI 3 specifications for the API-serving services.
- Rebuilt the test foundation: backend-free suites (in-memory auth, embedded Neo4j/Mongo/MariaDB), a full JUnit 4 → 5 migration, a REST integration-smoke harness, and table-driven authorization, permission, and artifact-lifecycle matrices.