Name: jsonld.js
Owner: Digital Bazaar, Inc.
Description: A JSON-LD Processor and API implementation in JavaScript
Created: 2011-08-23 02:14:31.0
Updated: 2018-01-14 08:06:04.0
Pushed: 2018-01-15 18:13:48.0
Homepage: http://json-ld.org/
Size: 2923
Language: JavaScript
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This library is an implementation of the JSON-LD specification in JavaScript.
JSON, as specified in RFC7159, is a simple language for representing objects on the Web. Linked Data is a way of describing content across different documents or Web sites. Web resources are described using IRIs, and typically are dereferencable entities that may be used to find more information, creating a “Web of Knowledge”. JSON-LD is intended to be a simple publishing method for expressing not only Linked Data in JSON, but for adding semantics to existing JSON.
JSON-LD is designed as a light-weight syntax that can be used to express Linked Data. It is primarily intended to be a way to express Linked Data in JavaScript and other Web-based programming environments. It is also useful when building interoperable Web Services and when storing Linked Data in JSON-based document storage engines. It is practical and designed to be as simple as possible, utilizing the large number of JSON parsers and existing code that is in use today. It is designed to be able to express key-value pairs, RDF data, RDFa data, Microformats data, and Microdata. That is, it supports every major Web-based structured data model in use today.
The syntax does not require many applications to change their JSON, but easily add meaning by adding context in a way that is either in-band or out-of-band. The syntax is designed to not disturb already deployed systems running on JSON, but provide a smooth migration path from JSON to JSON with added semantics. Finally, the format is intended to be fast to parse, fast to generate, stream-based and document-based processing compatible, and require a very small memory footprint in order to operate.
install jsonld
s
t jsonld = require('jsonld');
install jsonld
Use your favorite technology to load node_modules/dist/jsonld.min.js.
To use CDNJS include this script tag:
ipt src="https://cdnjs.cloudflare.com/ajax/libs/jsonld/0.5.17/jsonld.min.js"></script>
Check https://cdnjs.com/libraries/jsonld for the latest available version.
To use jsDeliver include this script tag:
ipt src="https://cdn.jsdelivr.net/npm/jsonld@0.5.17/dist/jsonld.min.js"></script>
See https://www.jsdelivr.com/package/npm/jsonld for the latest available version.
To use unpkg include this script tag:
ipt src="https://unpkg.com/jsonld@0.5.17/dist/jsonld.min.js"></script>
See https://unpkg.com/jsonld/ for the latest available version.
install npm:jsonld
js
rt * as jsonld from 'jsonld';
r
rt {promises} from 'jsonld';
r
rt {JsonLdProcessor} from 'jsonld';
doc = {
ttp://schema.org/name": "Manu Sporny",
ttp://schema.org/url": {"@id": "http://manu.sporny.org/"},
ttp://schema.org/image": {"@id": "http://manu.sporny.org/images/manu.png"}
context = {
ame": "http://schema.org/name",
omepage": {"@id": "http://schema.org/url", "@type": "@id"},
mage": {"@id": "http://schema.org/image", "@type": "@id"}
ompact a document according to a particular context
ee: http://json-ld.org/spec/latest/json-ld/#compacted-document-form
ld.compact(doc, context, function(err, compacted) {
nsole.log(JSON.stringify(compacted, null, 2));
Output:
"@context": {...},
"name": "Manu Sporny",
"homepage": "http://manu.sporny.org/",
"image": "http://manu.sporny.org/images/manu.png"
ompact using URLs
ld.compact('http://example.org/doc', 'http://example.org/context', ...);
xpand a document, removing its context
ee: http://json-ld.org/spec/latest/json-ld/#expanded-document-form
ld.expand(compacted, function(err, expanded) {
Output:
"http://schema.org/name": [{"@value": "Manu Sporny"}],
"http://schema.org/url": [{"@id": "http://manu.sporny.org/"}],
"http://schema.org/image": [{"@id": "http://manu.sporny.org/images/manu.png"}]
xpand using URLs
ld.expand('http://example.org/doc', ...);
latten a document
ee: http://json-ld.org/spec/latest/json-ld/#flattened-document-form
ld.flatten(doc, (err, flattened) => {
all deep-level trees flattened to the top-level
rame a document
ee: http://json-ld.org/spec/latest/json-ld-framing/#introduction
ld.frame(doc, frame, (err, framed) => {
document transformed into a particular tree structure per the given frame
anonize (normalize) a document using the RDF Dataset Normalization Algorithm
URDNA2015), see: http://json-ld.github.io/normalization/spec/
ld.canonize(doc, {
gorithm: 'URDNA2015',
rmat: 'application/n-quads'
err, canonized) => {
canonized is a string that is a canonical representation of the document
that can be used for hashing, comparison, etc.
erialize a document to N-Quads (RDF)
ld.toRDF(doc, {format: 'application/n-quads'}, (err, nquads) => {
nquads is a string of N-Quads
eserialize N-Quads (RDF) to JSON-LD
ld.fromRDF(nquads, {format: 'application/n-quads'}, (err, doc) => {
doc is JSON-LD
egister a custom async-callback-based RDF parser
ld.registerRDFParser(contentType, (input, callback) => {
parse input to a jsonld.js RDF dataset object...
llback(err, dataset);
egister a custom synchronous RDF parser
ld.registerRDFParser(contentType, input => {
parse input to a jsonld.js RDF dataset object... and return it
turn dataset;
se the promises API:
ompaction
t compacted = await jsonld.compact(doc, context);
xpansion
t expanded = await jsonld.expand(doc);
lattening
t flattened = await jsonld.flatten(doc);
raming
t framed = await jsonld.frame(doc, frame);
anonicalization (normalization)
t canonized = await jsonld.canonize(doc, {format: 'application/n-quads'});
erialize to RDF
t rdf = await jsonld.toRDF(doc, {format: 'application/n-quads'});
eserialize from RDF
t doc = await jsonld.fromRDF(nquads, {format: 'application/n-quads'});
egister a custom promise-based RDF parser
ld.registerRDFParser(contentType, async input => {
parse input into a jsonld.js RDF dataset object...
turn new Promise(...);
ow to override the default document loader with a custom one -- for
xample, one that uses pre-loaded contexts:
efine a mapping of context URL => context doc
t CONTEXTS = {
ttp://example.com": {
"@context": ...
...
rab the built-in node.js doc loader
t nodeDocumentLoader = jsonld.documentLoaders.node();
r grab the XHR one: jsonld.documentLoaders.xhr()
hange the default document loader using the callback API
you can also do this using the promise-based API, return a promise instead
f using a callback)
t customLoader = (url, callback) => {
(url in CONTEXTS) {
return callback(
null, {
contextUrl: null, // this is for a context via a link header
document: CONTEXTS[url], // this is the actual document that was loaded
documentUrl: url // this is the actual context URL after redirects
});
call the underlining documentLoader using the callback API.
deDocumentLoader(url, callback);
Note: By default, the node.js document loader uses a callback, but
owser-based document loaders (xhr or jquery) return promises if they
e supported (or polyfilled) in the browser. This behavior can be
ntrolled with the 'usePromise' option when constructing the document
ader. For example: jsonld.documentLoaders.xhr({usePromise: false}); */
ld.documentLoader = customLoader;
lternatively, pass the custom loader for just a specific call:
t compacted = await jsonld.compact(
context, {documentLoader: customLoader});
jsonld that exposes
most of the basic jsonld.js API.Commercial support for this library is available upon request from Digital Bazaar: support@digitalbazaar.com
The source code for the JavaScript implementation of the JSON-LD API is available at:
http://github.com/digitalbazaar/jsonld.js
This library includes a sample testing utility which may be used to verify that changes to the processor maintain the correct output.
The main test suites are included in external repositories. Check out each of the following:
https://github.com/json-ld/json-ld.org
https://github.com/json-ld/normalization
They should be sibling directories of the jsonld.js directory or in a
test-suites dir. To clone shallow copies into the test-suites dir you can
use the following:
npm run fetch-test-suites
Node.js tests can be run with a simple command:
npm test
If you installed the test suites elsewhere, or wish to run other tests, use
the JSONLD_TESTS environment var:
JSONLD_TESTS="/tmp/org/test-suites /tmp/norm/tests" npm test
Browser testing can be done with Karma:
npm test-karma
npm test-karma -- --browsers Firefox,Chrome
Code coverage of node tests can be generated in coverage/:
npm run coverage
To display a full coverage report on the console from coverage data:
npm run coverage-report
The Mocha output reporter can be changed to min, dot, list, nyan, etc:
REPORTER=dot npm test
Remote context tests are also available:
# run the context server in the background or another terminal
node tests/remote-context-server.js
JSONLD_TESTS=./tests npm test
To generate earl reports:
# generate the earl report for node.js
EARL=earl-node.jsonld npm test
# generate the earl report for the browser
EARL=earl-firefox.jsonld npm test-karma -- --browser Firefox