YANG Tools has shipped version 2.0.1 in Oxygen, with major code refactoring under the hood and in developer-visible APIs pertaining to YANG metamodel.

The most user-visible change is that in-memory data tree now enforces mandatory leaf node presence for operational store by default. This can be tweaked via the DataTreeConfiguration interface on a per-instance basis, if need be, but we recommend against switching it off.

For downstream users using karaf packaging, we have split our features into stable and experimental ones. Stable features are available from features-yangtools and contain the usual set of functionality, which will only expand in its capabilities. Experimental features are available from features-yangtools-experimental and carry functionality which is not stabilized yet and may get removed – this currently includes ObjectCache, which is slated for removal, as Guava's Interners are better suited for the job.

Users of yang-maven-plugin will find that YANG files packaged in jars now have their names normalized to RFC7950 guidelines. This includes using the actual module or submodule name as well as capturing the revision in the filename.

YANG codecs have seen a major shift, with the old XML parser in yang-data-impl removed in favor of yang-data-codec-xml and yang-data-codec-gson gaining the ability to parse and emit RFC7951 documents – allowing RFC8040 NETCONF module to come closer to full compliance. Since the SchemaContext is much more usable now, with Modules being indexed by their QNameModule, the codec operations have become significantly faster.

YANG parser has been extended with semantic knowledge of RFCs defined in RFC6536, RFC7952, RFC8040 and OpenConfig extensions.