sudoc/index.js

a wrapper around sudoc webservices

'use strict';

let request = require('request');
let baseUrl = 'http://www.sudoc.fr/services';

function query(service, params, callback) {

  let arrayQuery = Array.isArray(params);
  params = arrayQuery ? params.join(',') : params || '';

  let options = {
    uri: encodeURI(`${baseUrl}/${service}/${params}`),
    headers: { 'Accept': 'text/json' }
  };

  request.get(options, (err, res, body) => {
    if (err) { return callback(err); }

    let sudoc;

    try {
      sudoc = JSON.parse(body).sudoc;
    } catch (e) {
      return callback(e);
    }

    if (sudoc.error) {
      return callback(null, null);
    }

    if (arrayQuery && !Array.isArray(sudoc)) {
      sudoc = [sudoc];
    }

    callback(null, sudoc);
  });
}

['issn2ppn', 'isbn2ppn', 'ean2ppn'].forEach(service => {
  exports[service] = function (params, callback) {
    if (typeof callback === 'function') { return query(service, params, callback); }

    return new Promise((resolve, reject) => {
      query(service, params, (err, sudoc) => {
        if (err) { return reject(err); }
        resolve(sudoc);
      });
    });
  };
});