The Discovery attribute based access control language is a presented as a JSON based profile of the XACML language, modified to use the information model query language to express policy rules.
The language is used to support some of the data access authorisation processes as described in the specification - Identity, authentication and authorisation . This article specifies the requirements of the language and the grammar it uses. Whilst presented as JSON, in line with other components of the information modelling language, the syntax can be accessed via the information model XSD schemaon the discovery github and example content viewed in the information manager data files folder