MetHAL

Wrapper around the HAL API. It allows to query the HAL database in a convenient way.

## Install

  npm install --save @ezpaarse-project/methal

Usage

  var methal = require('methal');

  methal.query({ docid: '19' }, { fields: '*' }, function (err, result) {
    console.log(result);
  });

Methods

query(search, [options,] callback)

Perform a query and get the JSON response from the API. The callback is called with a potential error and the result object. (see below)

Result example

{
  "response":{
    // number of documents that match the query
    "numFound": 1,
    // index of the first document
    "start": 0,
    // actual documents (NB: the amount is limited by default)
    "docs":[{
      "docid": 19,
      "uri_s": "https://hal.archives-ouvertes.fr/hal-00000019",
      "label_s": "Mark Wexler, Francesco Panerai, Ivan Lamouret, Jacques Droulez. Self-motion and the perception of stationary objects. Nature, Nature Publishing Group, 2001, 409, pp.85-88. <hal-00000019>"
    }]
  }
}

find(search, [options,] callback)

Shorthand function to get multiple documents. Returns only the docs instead of the full JSON.

findOne(search, [options,] callback)

Shorthand function to get a single document. Limit the query to one row and returns only the doc instead of the full JSON.

Querying

The search can be eiter an object or a raw query string that use Solr syntax. The object supports $and, $or and $not operators between fields.

Have a look at the API documentation to get a list of all available fields.

Query examples

// city contains "Paris"
{ city_t: 'paris' }

// city equals "Paris"
{ city_s: 'Paris' }

// city contains either "Paris" or "London"
{ city_t: 'paris OR london' }

// title contains "milk" and (city equals "London" or language equals "en")
{
  title_t: 'milk',
  $or: [
    { city_s: 'London' },
    { language_s: 'en' }
  ]
}

// city equals "Paris" and (language is not "fr" and fulltext does not contain "milk")
{
  { city_s: 'Paris' },
  $not: [
    { language_s: 'fr' },
    { fulltext_t: 'milk' }
  ]
}

Main options

Have a look at the API documentation to get a full list of available options.

Option	Description
sort	Sort results. Ex: "city_s asc", "language_s desc"
start	Offset of the first document to return.
rows	Number of documents to return (limited by default).
fl / fields	Fields to return. Ex: "*", "docid, country_s", ["docid", "country_s"]
host	Host of the API (optional default to public API: http://api.archives-ouvertes.fr)
core	API core: `search`, `ref/instance`, `hal` (hal team internal use). Default to `search`.