oembedder

Delivers the embedded representation of a URL if one is provided or tries to create it with the information present on the given URL.

Installation

npm i oembedder

Usage

The oembedder module exports a function that accepts two parameters, the url of the resource to get the oEmbed format and an optional configuration object that might contain custom selectors to extract values from a specific resource and/or the provider url.

If a provider url is given the custom selectors are superfluous.

Configuration

The configuration consists of the following two properties (provider, selectors).

Provider

You can find the oEmbed provider from the oembed.com list, or you might know a provider that is not listed there.

Example provider for youtube:

{
  "provider_name": "YouTube",
  "provider_url": "https://www.youtube.com/",
  "endpoints": [
    {
      "url": "https://www.youtube.com/oembed",
      "discovery": true
    }
  ]
}

The above JSON is retrieved from oembed.com and the library expects the https://www.youtube.com/oembed endpoint from the endpoints array.

If you have a provider that is not included in the list you could follow the instructions and submit it.

The oembedder returns a promise that resolves to the oEmbed format of the requested resource, as a javascript object.

Example with provider

Usage:

const oembedder = require('oembedder');

const provider = 'https://www.youtube.com/oembed';
const url = 'https://www.youtube.com/watch?v=_avbO-ckwQw';

oembedder(url, provider)
  .then(console.log)
  .catch(console.log);

Response

{
  author_url: 'https://www.youtube.com/user/NBA',
  type: 'video',
  provider_url: 'https://www.youtube.com/',
  thumbnail_url: 'https://i.ytimg.com/vi/_avbO-ckwQw/hqdefault.jpg',
  thumbnail_width: 480,
  html: '<iframe width="480" height="270" src="https://www.youtube.com/embed/_avbO-ckwQw?feature=oembed" frameborder="0" allow="autoplay; encrypted-media" allowfullscreen></iframe>',
  provider_name: 'YouTube',
  thumbnail_height: 360,
  height: 270,
  title: '2018 NBA Finals Game 4 Mini-Movie',
  author_name: 'NBA',
  version: '1.0',
  width: 480
}

Example without provider

If you don't know the provider or there is no oEmbed provider to a specific url. The library will try to resolve the oEmbed format of the resource.

Usage:

const oembedder = require('oembedder');

const url = 'http://www.bbc.com/capital/story/20180626-why-owls-might-suffer-in-a-cashless-society';

oembedder(url)
  .then(console.log)
  .catch(console.log);

Response

{
  version: '1.0',
  type: 'link',
  title: 'The strange reason owl theft may be on the rise ',
  provider_url: 'http://www.bbc.com/',
  provider_name: 'www.bbc.com',
  author_url: 'http://www.bbc.com/',
  author_name: 'Richard Gray',
  thumbnail_url:'http://ichef.bbci.co.uk/wwfeatures/live/624_351/images/live/p0/6c/29/p06c29f1.jpg',
  thumbnail_width: 624,
  thumbnail_height: 351
}

Selectors

You can use selectors to extract information from a specific page for a specific property of the oEmbed format. If no selectors are provided a set of default selectors will be used to extract this information. You can overwrite part or all of the default selectors by passing a custom selector for an oEmbed property.

The current library supports attribute values of matched element, text within its html tag, or the html content.

The selectors configuration accepts a set of selector objects per property, in case that the information needs to be extracted and combined from a series of html elements.

Property	Default selector(s)	text	attribute	Default value
title	h1, h2, div[class$=title]	true		undefined
providerUrl				resource domain
providerName	meta[property=site_name]	false	content	resource host
authorUrl				provider url
authorName	meta[name=author]	false	content	resource host
thumbnail	meta[property="og:image"]	false	content	undefined
text*				undefined
htmlText**				undefined

* The text property is an extension to possibly extract the text of a resource, which is not defined in the oembed.com provider response.

** The htmlText property is another extension to possibly extract the text of a resource, similarly with the text property above, but including the html markup.

Those too extensions intent to enrich the oEmbed format for a better representation on the web.

Example with custom selectors

The following configuration of selectors is set to extract the author name and url of blog post on medium.com.

const oembedder = require('oembedder');

const selectors = {
  authorName: [
    {
      selector: 'meta[property="author"]',
      attribute: 'content'
    }
  ],
  authorUrl: [
    {
      selector: 'link[rel="author"]',
      attribute: 'href'
    }
  ]
};

const url = 'https://medium.com/the-node-js-collection/native-extensions-for-node-js-767e221b3d26';

oembedder(url, { selectors })
  .then(console.log)
  .catch(console.log);

Example with customer selectors (extract text)

const oembedder = require('oembedder');

const selectors = {
  authorName: [
    {
      selector: 'meta[property="author"]',
      attribute: 'content'
    }
  ],
  authorUrl: [
    {
      selector: 'link[rel="author"]',
      attribute: 'href'
    }
  ],
  text: [
    {
      selector: '.section-content',
      text: true
    }
  ]
};

const url = 'https://medium.com/the-node-js-collection/native-extensions-for-node-js-767e221b3d26';

oembedder(url, { selectors })
  .then(console.log)
  .catch(console.log);

Http options

The configuration of the module allows the user to set some information of the http GET request. The allowed options are the following:

http option	Default value	Description
encoding	utf-8	The encoding to be used by the request
followRedirect	true	To follow or not 3xx responses as redirects
gzip	true	Requests compressed content or not
headers	undefined	A JS object with http header info
timeout		After the timeout in ms the request will respond with ESOCKETTIMEDOUT error

Example with http options

const oembedder = require('oembedder');

const url = 'https://medium.com/the-node-js-collection/native-extensions-for-node-js-767e221b3d26';

const httpOptions = {
  timeout: 5000 // sets the request timeout to 5 seconds
};

oembedder(url, { httpOptions })
  .then(console.log)
  .catch(console.log);

Limitations

At the moment the library only resolves oEmbeds of type link for the resources that no provider is given or matched.

License