Support default values for @type when framing.

Author: gkellogg

CHANGELOG.md

@@ -39,6 +39,7 @@
   'i18n-datatype'.
 - Top level `@graph` omitted if `omitGraph` is `true`.
 - Check for invalid values of `@embed`.
+- Support default values for `@type` when framing.
 
 ## 2.0.2 - 2020-01-17
 

lib/expand.js

@@ -515,7 +515,20 @@ async function _expandObject({
     }
 
     if(expandedProperty === '@type') {
-      _validateTypeValue(value);
+      // if framing, can be a default object, but need to expand
+      // key to determine that
+      if(_isObject(value)) {
+        const expandedValue = {};
+        for(const [k, v] of Object.entries(value)) {
+          const kk = _expandIri(typeScopedContext, k, {vocab: true});
+          const vv = _asArray(v).map(vvv =>
+            _expandIri(typeScopedContext, vvv, {base: true, vocab: true})
+          );
+          expandedValue[kk] = vv;
+        }
+        value = expandedValue;
+      }
+      _validateTypeValue(value, options.isFrame);
       _addValue(
         expandedParent, '@type',
         _asArray(value).map(v =>

lib/frame.js

@@ -270,7 +270,14 @@ api.frame = (state, subjects, frame, parent, property = null) => {
     // handle defaults
     for(const prop of Object.keys(frame).sort()) {
       // skip keywords
-      if(isKeyword(prop)) {
+      if(prop === '@type') {
+        if(!types.isObject(frame[prop][0]) ||
+           !frame[prop][0].hasOwnProperty('@default'))
+        {
+          continue;
+        }
+        // allow through default types
+      } else if(isKeyword(prop)) {
         continue;
       }
 
@@ -526,18 +533,24 @@ function _filterSubject(state, subject, frame, flags) {
           matchThis = true;
         } else if(frame['@type'].length === 1 &&
           types.isEmptyObject(frame['@type'][0])) {
-          // match on wildcard @type
+          // match on wildcard @type if there is a type
           matchThis = nodeValues.length > 0;
         } else {
           // match on a specific @type
           for(const type of frame['@type']) {
-            if(nodeValues.some(tt => tt === type)) {
-              return true;
+            if(types.isObject(type) && '@default' in type) {
+              // match on default object
+              matchThis = true;
+            } else {
+              matchThis = matchThis || nodeValues.some(tt => tt === type);
             }
           }
-          return false;
+        }
+        if(!flags.requireAll) {
+          return matchThis;
         }
       }
+      continue;
     }
 
     // Forc a copy of this frame entry so it can be manipulated

lib/jsonld.js

@@ -48,7 +48,9 @@ const {fromRDF: _fromRDF} = require('./fromRdf');
 const {toRDF: _toRDF} = require('./toRdf');
 
 const {
-  frameMergedOrDefault: _frameMergedOrDefault
+  frameMergedOrDefault: _frameMergedOrDefault,
+  cleanupNull: _cleanupNull,
+  cleanupPreserve: _cleanupPreserve
 } = require('./frame');
 
 const {
@@ -70,8 +72,7 @@ const {
 
 const {
   compact: _compact,
-  compactIri: _compactIri,
-  removePreserve: _removePreserve
+  compactIri: _compactIri
 } = require('./compact');
 
 const {
@@ -225,12 +226,6 @@ jsonld.compact = async function(input, ctx, options) {
     ctx = ctx[0];
   }
 
-  if(options.framing) {
-    // remove @preserve from results
-    options.link = {};
-    compacted = _removePreserve(activeCtx, compacted, options);
-  }
-
   // add context and/or @graph
   if(_isArray(compacted)) {
     // use '@graph' keyword
@@ -493,13 +488,17 @@ jsonld.frame = async function(input, frame, options) {
   opts.is11 = _processingMode(activeCtx, 1.1);
 
   // do framing
-  const framed = _frameMergedOrDefault(expanded, expandedFrame, opts);
+  let framed = _frameMergedOrDefault(expanded, expandedFrame, opts);
 
   opts.graph = !options.omitGraph;
   opts.skipExpansion = true;
   opts.link = {};
   opts.framing = true;
-  const compacted = await jsonld.compact(framed, frameContext, opts);
+  let compacted = await jsonld.compact(framed, frameContext, opts);
+
+  // replace @null with null, compacting arrays
+  opts.link = {};
+  compacted = _cleanupNull(compacted, opts);
 
   return compacted;
 };

lib/util.js

@@ -147,31 +147,33 @@ api.parseLinkHeader = header => {
  *
  * @param v the value to check.
  */
-api.validateTypeValue = v => {
-  // can be a string or an empty object
-  if(types.isString(v) || types.isEmptyObject(v)) {
+api.validateTypeValue = (v, isFrame) => {
+  if(types.isString(v)) {
     return;
   }
 
-  // must be an array
-  let isValid = false;
-  if(types.isArray(v)) {
-    // must contain only strings
-    isValid = true;
-    for(let i = 0; i < v.length; ++i) {
-      if(!(types.isString(v[i]))) {
-        isValid = false;
-        break;
-      }
+  if(types.isArray(v) && v.every(vv => types.isString(vv))) {
+    return;
+  } else if(isFrame && types.isObject(v)) {
+    switch(Object.keys(v).length) {
+      case 0:
+        // empty object is wildcard
+        return;
+      case 1:
+        // default entry is all strings
+        if('@default' in v &&
+           api.asArray(v['@default']).every(vv => types.isString(vv)))
+        {
+          return;
+        }
     }
   }
 
-  if(!isValid) {
-    throw new JsonLdError(
-      'Invalid JSON-LD syntax; "@type" value must a string, an array of ' +
-      'strings, or an empty object.', 'jsonld.SyntaxError',
-      {code: 'invalid type value', value: v});
-  }
+  throw new JsonLdError(
+    'Invalid JSON-LD syntax; "@type" value must a string, an array of ' +
+    'strings, an empty object, ' +
+    'or a default object.', 'jsonld.SyntaxError',
+    {code: 'invalid type value', value: v});
 };
 
 /**

tests/test-common.js

@@ -126,18 +126,12 @@ const TEST_TYPES = {
       specVersion: ['json-ld-1.0'],
       // FIXME
       idRegex: [
-        // default value for @type
-        /frame-manifest.jsonld#t0064$/,
-        // @container: @graph
-        /frame-manifest.jsonld#tg010$/,
         // blank nodes
         /frame-manifest.jsonld#t0052$/,
         /frame-manifest.jsonld#t0053$/,
         // lists
         /frame-manifest.jsonld#t0055$/,
         /frame-manifest.jsonld#t0058$/,
-        // @preserve and @container: @set
-        /frame-manifest.jsonld#t0062$/,
         // requireAll
         /frame-manifest.jsonld#tra01$/,
         /frame-manifest.jsonld#tra02$/,