Improve metadata extraction (#478)

* Improve metadata extraction

* Recognize meta[property] as a space-separated list
* Recognize Dulin Core (dc|dcterm): metadata.
* Prefer Dublin Core, Open Graph, Twitter, and HTML in that order.
* _getArticleTitle() is now only used as fallback if document
 doesn't provide good metadata.
33 files changed
tree: 4c81cc5064e32ecbf4ec23158bba2ebe06aa2a19
  1. .eslintrc.js
  2. .gitignore
  3. .npmignore
  4. .travis.yml
  5. JSDOMParser.js
  7. Readability.js
  8. benchmarks/
  9. index.js
  10. package.json
  11. test/


Build Status

A standalone version of the readability library used for Firefox Reader View. Any changes to Readability.js itself should be reviewed by an appropriate Firefox/toolkit peer, such as @gijsk, since these changes will be automatically merged to mozilla-central.


For outstanding issues, see the issue list in this repo, as well as this bug list.

To test local changes to Readability.js, you can use the automated tests. There's a node script to help you create new ones.

Please make sure to run eslint against any proposed changes when creating a pull request.


To parse a document, you must create a new Readability object from a document object, and then call parse(). Here's an example:

var article = new Readability(document).parse();

This article object will contain the following properties:

  • title: article title
  • content: HTML string of processed article content
  • length: length of an article, in characters
  • excerpt: article description, or short excerpt from the content
  • byline: author metadata
  • dir: content direction

If you're using Readability on the web, you will likely be able to use a document reference from elsewhere (e.g. fetched via XMLHttpRequest, in a same-origin <iframe> you have access to, etc.).

Otherwise, you would need to construct such an object using a DOM parser such as jsdom. While this repository contains a parser of its own (JSDOMParser), that is restricted to reading XML-compatible markup and therefore we do not recommend it for general use.

If you‘re using jsdom to create a DOM object, you should ensure that the page doesn’t run (page) scripts (avoid fetching remote resources etc.) as well as passing it the page's URI as the url property of the options object you pass the JSDOM constructor.


Readability's parse() works by modifying the DOM. This removes some elements in the web page. You could avoid this by passing the clone of the document object while creating a Readability object.

var documentClone = document.cloneNode(true); 
var article = new Readability(documentClone).parse();


Please run eslint as a first check that your changes adhere to our style guidelines.

To run the test suite:

$ mocha test/test-*.js

To run a specific test page by its name:

$ mocha test/test-*.js -g 001

To run the test suite in TDD mode:

$ mocha test/test-*.js -w

Combo time:

$ mocha test/test-*.js -w -g 001


Benchmarks for all test pages:

$ npm run perf

Reference benchmark:

$ npm run perf-reference


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See the License for the specific language governing permissions and
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