This npm package is a plugin to citation.js (see this article) that outputs bibliographic information to Wikidata QuickStatements. Some important points:

1. it does not (currently) check if the information is already in Wikidata
2. it only supports journals articles (at this moment)

npm install @citation-js/plugin-quickstatements

To run the below example, you also need to install a few other packages (as they are currently not automatically pulled in, it seems):

npm install @citation-js/core @citation-js/plugin-pubmed @citation-js/plugin-doi @babel/register @babel/core

Install the plugin by require-ing it:

require('@citation-js/plugin-quickstatements')

Formats and other features added by this plugin.

The input is CSL generated by citation.js by any of its supported formats. Here's an example for how to create QuickStatements for a PubMed Central identifier:

c = require('@citation-js/core')
require('@citation-js/plugin-pubmed')
require('@citation-js/plugin-doi')

require('@babel/register')
require('@citation-js/plugin-quickstatements')

c.Cite.async([
  '10.1186/s13321-019-0380-5',
  'pmid:14266813',
  'PMC6613236'
])
  .then(Cite =>
    console.log(Cite.format('quickstatements'))
  )
  .catch(console.error)

Or for book ISBN numbers:

const c = require('@citation-js/core')
require('@citation-js/plugin-isbn')

require('@babel/register')
require('@citation-js/plugin-quickstatements')

c.Cite.async([
  '978-0956775016'
])
  .then(Cite =>
    console.log(Cite.format('quickstatements'))
  )
  .catch(console.error)

The output is QuickStatements to be copied into the online webservice. The output looks like:

	CREATE

	LAST	P31	Q13442814
	LAST	Len	"Journal of Cheminformatics, ORCID, and GitHub"
	LAST	P304	"44"
	LAST	P356	"10.1186/s13321-019-0365-4"
	LAST	P433	"1"
	LAST	P478	"11"
	LAST	P698	"31281945"
	LAST	P932	"PMC6613236"
	LAST	P1476	"Journal of Cheminformatics, ORCID, and GitHub"
	LAST	P577	"2019-07-08"
	LAST	P2093	"Egon Willighagen"	P1545	"1"	
	LAST	P2093	"Nina Jeliazkova"	P1545	"2"	
	LAST	P2093	"Rajarshi Guha"	P1545	"3"