Shapes Constraint Language (SHACL) Draft Published

The RDF Data Shapes Working Group has published a Working Draft of Shapes Constraint Language (SHACL). SHACL (Shapes Constraint Language) is a language for describing and constraining the contents of RDF graphs. SHACL groups these descriptions and constraints into "shapes", which specify conditions that apply at a given RDF node. Shapes provide a high-level vocabulary to identify predicates and their associated cardinalities, datatypes and other constraints. Additional constraints can be associated with shapes using SPARQL and similar extension languages. These extension languages can also be used to define new high-level vocabulary terms. SHACL shapes can be used to communicate information about data structures associated with some process or interface, generate or validate data, or drive user interfaces. This document defines the SHACL language and its underlying semantics.