Improve structure of .well-known/void schema

package.json

@@ -22,9 +22,9 @@
     "@fortawesome/free-solid-svg-icons": "^5.15.3",
     "@fortawesome/vue-fontawesome": "^2.0.2",
     "@rdfjs-elements/rdf-editor": "^0.4.1",
+    "@rdfjs/namespace": "^1.1.0",
     "@rdfjs/serializer-jsonld-ext": "^2.0.0",
     "@rdfjs/term-set": "1.0.2",
-    "@tpluscode/rdf-ns-builders": "^0.4.2",
     "@tpluscode/rdf-string": "0.2.23",
     "@zazuko/rdf-vocabularies": "2021.3.31",
     "buefy": "^0.9.7",

src/components/SettingsPane.vue

@@ -43,7 +43,7 @@
           Force introspection
         </b-switch>
         <p class="help">
-          By default, the explorer will use the endpoint schema provided at <code>endpoint/.well-known/schema</code>
+          By default, the explorer will use the endpoint schema provided at <code>endpoint/.well-known/void</code>
           (if any). Use this option to force an introspection.
         </p>
       </b-field>

src/endpoint.js

@@ -1,11 +1,12 @@
+import clownface from 'clownface'
 import RDF from 'rdf-ext'
 import ParsingClient from 'sparql-http-client/ParsingClient'
 import TermSet from '@rdfjs/term-set'
-import _prefixes from '@zazuko/rdf-vocabularies/prefixes'
 import { shrink } from '@zazuko/rdf-vocabularies/shrink'
 import { tablesFromSHACL } from '@/shacl'
+import { rdf, schema, spex, prefixes as _prefixes } from './namespace'
 
-const SCHEMA_URI = '.well-known/schema'
+const SCHEMA_URI = '.well-known/void'
 
 const initialPrefixes = [...Object.keys(_prefixes)]
 
@@ -54,9 +55,7 @@ export class Endpoint {
 
     const tables = await this.fetchSHACL()
 
-    return tables.length > 0
-      ? tables
-      : this.introspectTables()
+    return tables || this.introspectTables()
   }
 
   /**
@@ -71,9 +70,15 @@ export class Endpoint {
       ${fromClause}
     `
     const quads = await this.client.query.construct(query)
-    const dataset = RDF.dataset(quads)
+    const dataset = clownface({
+      dataset: RDF.dataset(quads),
+      term: RDF.namedNode(schemaURI),
+    })
+    const defaultShapes = dataset.out(spex.shapes).has(rdf.type, spex.DefaultShapes)
 
-    return tablesFromSHACL(dataset, this)
+    return defaultShapes.term
+      ? tablesFromSHACL(defaultShapes.out(schema.hasPart), this)
+      : null
   }
 
   async introspectTables () {

src/namespace.js

@@ -0,0 +1,13 @@
+import namespace from '@rdfjs/namespace'
+import prefixes from '@zazuko/rdf-vocabularies/prefixes'
+
+prefixes.spex = 'https://ld.zazuko.com/spex/'
+
+export const rdf = namespace(prefixes.rdf)
+export const schema = namespace(prefixes.schema)
+export const sh = namespace(prefixes.sh)
+export const spex = namespace(prefixes.spex)
+
+export {
+  prefixes
+}

src/shacl.js

@@ -1,10 +1,15 @@
-import clownface from 'clownface'
-import { rdf, sh } from '@tpluscode/rdf-ns-builders'
-import _prefixes from '@zazuko/rdf-vocabularies/prefixes'
-
+import { sh, prefixes } from './namespace'
+
+/**
+ * Serializes a list of a tables as a SHACL graph.
+ *
+ * @param {Array} tables - List of tables
+ * @param {Endpoint} endpoint
+ * @returns Object - JSON-LD SHACL
+ */
 export function tablesToSHACL (tables, endpoint) {
-  const prefixes = endpoint.prefixes.reduce((acc, { prefix, url }) => ({ ...acc, [prefix]: url }), {})
-  const context = { ..._prefixes, ...prefixes }
+  const customPrefixes = endpoint.prefixes.reduce((acc, { prefix, url }) => ({ ...acc, [prefix]: url }), {})
+  const context = { ...prefixes, ...customPrefixes }
 
   const graph = tables.map((table) => {
     return {
@@ -33,16 +38,23 @@ export function tablesToSHACL (tables, endpoint) {
 
   return {
     '@context': context,
-    '@graph': graph,
+    '@graph': {
+      '@type': 'spex:DefaultShapes',
+      'schema:hasPart': graph,
+    },
   }
 }
 
-export function tablesFromSHACL (dataset, endpoint) {
-  const cf = clownface({ dataset })
-
-  const shapes = cf.has(rdf.type, sh.NodeShape).toArray()
-
+/**
+ * Extracts a list of tables from an RDF graph.
+ *
+ * @param {Clownface} shapes - Pointer to node shapes
+ * @param {Endpoint} endpoint
+ * @returns
+ */
+export function tablesFromSHACL (shapes, endpoint) {
   return shapes
+    .toArray()
     .map((shape) => {
       const targetClass = shape.out(sh.targetClass).term
 

src/views/ShaclEditor.vue

@@ -39,8 +39,10 @@ import { Splitpanes, Pane } from 'splitpanes'
 import 'splitpanes/dist/splitpanes.css'
 import '@rdfjs-elements/rdf-editor'
 import { parsers } from '@rdf-esm/formats-common'
+import clownface from 'clownface'
 import OverviewTables from '@/components/OverviewTables.vue'
 import { tablesFromSHACL } from '@/shacl'
+import { rdf, sh } from '@/namespace'
 
 const formats = [...parsers.keys()]
 
@@ -82,7 +84,8 @@ export default {
       try {
         const quads = await editor.quads
         const dataset = RDF.dataset(quads)
-        this.tables = tablesFromSHACL(dataset, endpoint)
+        const shapes = clownface({ dataset }).has(rdf.type, sh.NodeShape)
+        this.tables = tablesFromSHACL(shapes, endpoint)
       } catch (e) {
         this.error = e.toString()
       }