Support literal JSON.

Author: davidlehn

CHANGELOG.md

@@ -1,5 +1,10 @@
 # jsonld ChangeLog
 
+### Added
+- Support literal JSON.
+  - Use JCS node-es6 canonicalize code from
+    https://github.com/cyberphone/json-canonicalization/
+
 ## 1.7.0 - 2019-08-30
 
 ### Added

lib/constants.js

@@ -17,6 +17,7 @@ module.exports = {
   RDF_TYPE: RDF + 'type',
   RDF_PLAIN_LITERAL: RDF + 'PlainLiteral',
   RDF_XML_LITERAL: RDF + 'XMLLiteral',
+  RDF_JSON_LITERAL: RDF + 'JSON',
   RDF_OBJECT: RDF + 'object',
   RDF_LANGSTRING: RDF + 'langString',
 

lib/context.js

@@ -499,7 +499,7 @@ api.createTermDefinition = (
         {code: 'invalid type mapping', context: localCtx});
     }
 
-    if(type !== '@id' && type !== '@vocab') {
+    if(type !== '@id' && type !== '@vocab' && type !== '@json') {
       // expand @type to full IRI
       type = _expandIri(
         activeCtx, type, {vocab: true, base: false}, localCtx, defined,

lib/expand.js

@@ -669,6 +669,12 @@ function _expandObject({
           insideList: isList,
           expansionMap
         });
+      } else if(
+        _getContextValue(activeCtx, key, '@type') === '@json') {
+        expandedValue = {
+          '@type': '@json',
+          '@value': value
+        };
       } else {
         // recursively expand value with key as new active property
         expandedValue = api.expand({

lib/fromRdf.js

@@ -17,6 +17,7 @@ const {
   RDF_TYPE,
   // RDF_PLAIN_LITERAL,
   // RDF_XML_LITERAL,
+  RDF_JSON_LITERAL,
   // RDF_OBJECT,
   // RDF_LANGSTRING,
 
@@ -285,6 +286,10 @@ function _RDFToObject(o, useNativeTypes) {
     if(!type) {
       type = XSD_STRING;
     }
+    if(type === RDF_JSON_LITERAL) {
+      type = '@json';
+      rval['@value'] = JSON.parse(rval['@value']);
+    }
     // use native types for certain xsd types
     if(useNativeTypes) {
       if(type === XSD_BOOLEAN) {

lib/json-canonicalize.js

@@ -0,0 +1,65 @@
+// https://github.com/cyberphone/json-canonicalization
+// https://www.apache.org/licenses/LICENSE-2.0
+/* eslint-disable */
+
+// ES6 based JSON canonicalizer
+'use strict';
+var canonicalize = function(object) {
+
+    var buffer = '';
+    serialize(object);
+    return buffer;
+
+    function serialize(object) {
+        if (object === null || typeof object !== 'object' ||
+            object.toJSON != null) {
+            /////////////////////////////////////////////////
+            // Primitive type or toJSON - Use ES6/JSON     //
+            /////////////////////////////////////////////////
+            buffer += JSON.stringify(object);
+
+        } else if (Array.isArray(object)) {
+            /////////////////////////////////////////////////
+            // Array - Maintain element order              //
+            /////////////////////////////////////////////////
+            buffer += '[';
+            let next = false;
+            object.forEach((element) => {
+                if (next) {
+                    buffer += ',';
+                }
+                next = true;
+                /////////////////////////////////////////
+                // Array element - Recursive expansion //
+                /////////////////////////////////////////
+                serialize(element);
+            });
+            buffer += ']';
+
+        } else {
+            /////////////////////////////////////////////////
+            // Object - Sort properties before serializing //
+            /////////////////////////////////////////////////
+            buffer += '{';
+            let next = false;
+            Object.keys(object).sort().forEach((property) => {
+                if (next) {
+                    buffer += ',';
+                }
+                next = true;
+                ///////////////////////////////////////////////
+                // Property names are strings - Use ES6/JSON //
+                ///////////////////////////////////////////////
+                buffer += JSON.stringify(property);
+                buffer += ':';
+                //////////////////////////////////////////
+                // Property value - Recursive expansion //
+                //////////////////////////////////////////
+                serialize(object[property]);
+            });
+            buffer += '}';
+        }
+    }
+};
+
+module.exports = canonicalize;

lib/toRdf.js

@@ -6,6 +6,7 @@
 const {createNodeMap} = require('./nodeMap');
 const {isKeyword} = require('./context');
 const graphTypes = require('./graphTypes');
+const jsonCanonicalize = require('./json-canonicalize');
 const types = require('./types');
 const util = require('./util');
 
@@ -18,6 +19,7 @@ const {
   RDF_TYPE,
   // RDF_PLAIN_LITERAL,
   // RDF_XML_LITERAL,
+  RDF_JSON_LITERAL,
   // RDF_OBJECT,
   RDF_LANGSTRING,
 
@@ -224,8 +226,11 @@ function _objectToRDF(item, issuer, dataset, graphTerm) {
     let value = item['@value'];
     const datatype = item['@type'] || null;
 
-    // convert to XSD datatypes as appropriate
-    if(types.isBoolean(value)) {
+    // convert to XSD/JSON datatypes as appropriate
+    if(datatype === '@json') {
+      object.value = jsonCanonicalize(value);
+      object.datatype.value = RDF_JSON_LITERAL;
+    } else if(types.isBoolean(value)) {
       object.value = value.toString();
       object.datatype.value = datatype || XSD_BOOLEAN;
     } else if(types.isDouble(value) || datatype === XSD_DOUBLE) {

tests/test-common.js

@@ -60,16 +60,6 @@ const TEST_TYPES = {
         /compact-manifest.jsonld#tpi04$/,
         /compact-manifest.jsonld#tpi05$/,
         /compact-manifest.jsonld#tpi06$/,
-        // JSON literals
-        /compact-manifest.jsonld#tjs01$/,
-        /compact-manifest.jsonld#tjs02$/,
-        /compact-manifest.jsonld#tjs03$/,
-        /compact-manifest.jsonld#tjs04$/,
-        /compact-manifest.jsonld#tjs05$/,
-        /compact-manifest.jsonld#tjs06$/,
-        /compact-manifest.jsonld#tjs07$/,
-        /compact-manifest.jsonld#tjs08$/,
-        /compact-manifest.jsonld#tjs09$/,
         // IRI confusion
         /compact-manifest.jsonld#te002$/,
         // @propogate
@@ -164,18 +154,6 @@ const TEST_TYPES = {
         /expand-manifest.jsonld#tpi09$/,
         /expand-manifest.jsonld#tpi10$/,
         /expand-manifest.jsonld#tpi11$/,
-        // JSON literals
-        /expand-manifest.jsonld#tjs01$/,
-        /expand-manifest.jsonld#tjs02$/,
-        /expand-manifest.jsonld#tjs03$/,
-        /expand-manifest.jsonld#tjs04$/,
-        /expand-manifest.jsonld#tjs05$/,
-        /expand-manifest.jsonld#tjs06$/,
-        /expand-manifest.jsonld#tjs07$/,
-        /expand-manifest.jsonld#tjs08$/,
-        /expand-manifest.jsonld#tjs09$/,
-        /expand-manifest.jsonld#tjs10$/,
-        /expand-manifest.jsonld#tjs11$/,
         // misc
         /expand-manifest.jsonld#te043$/,
         /expand-manifest.jsonld#te044$/,
@@ -329,14 +307,6 @@ const TEST_TYPES = {
       specVersion: ['json-ld-1.0'],
       // FIXME
       idRegex: [
-        // JSON literals
-        /fromRdf-manifest.jsonld#tjs01$/,
-        /fromRdf-manifest.jsonld#tjs02$/,
-        /fromRdf-manifest.jsonld#tjs03$/,
-        /fromRdf-manifest.jsonld#tjs04$/,
-        /fromRdf-manifest.jsonld#tjs05$/,
-        /fromRdf-manifest.jsonld#tjs06$/,
-        /fromRdf-manifest.jsonld#tjs07$/,
       ]
     },
     fn: 'fromRDF',
@@ -399,20 +369,6 @@ const TEST_TYPES = {
         /html-manifest.jsonld#tr020$/,
         /html-manifest.jsonld#tr021$/,
         /html-manifest.jsonld#tr022$/,
-        // JSON literal
-        /toRdf-manifest.jsonld#tjs01$/,
-        /toRdf-manifest.jsonld#tjs02$/,
-        /toRdf-manifest.jsonld#tjs03$/,
-        /toRdf-manifest.jsonld#tjs04$/,
-        /toRdf-manifest.jsonld#tjs05$/,
-        /toRdf-manifest.jsonld#tjs06$/,
-        /toRdf-manifest.jsonld#tjs07$/,
-        /toRdf-manifest.jsonld#tjs08$/,
-        /toRdf-manifest.jsonld#tjs09$/,
-        /toRdf-manifest.jsonld#tjs10$/,
-        /toRdf-manifest.jsonld#tjs11$/,
-        /toRdf-manifest.jsonld#tjs12$/,
-        /toRdf-manifest.jsonld#tjs13$/,
         // number fixes
         /toRdf-manifest.jsonld#trt01$/,
         // IRI resolution