index.js

'use strict';

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.journals = exports.licenses = exports.types = exports.members = exports.funders = exports.works = exports.journalWorks = exports.memberWorks = exports.prefixWorks = exports.funderWorks = exports.journal = exports.type = exports.member = exports.prefix = exports.funder = exports.work = undefined;

var _typeof = typeof Symbol === "function" && typeof Symbol.iterator === "symbol" ? function (obj) { return typeof obj; } : function (obj) { return obj && typeof Symbol === "function" && obj.constructor === Symbol ? "symbol" : typeof obj; };

var _request = require('request');

var _request2 = _interopRequireDefault(_request);

var _assign = require('lodash/assign');

var _assign2 = _interopRequireDefault(_assign);

function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }

var endpoint = 'https://api.crossref.org/';
var timeout = 60 * 1000; // CrossRef is *very* slow

// make a request
function GET(path, cb) {
  // console.log(`### ${endpoint}${path}`);
  (0, _request2.default)({ url: '' + endpoint + path, json: true, timeout: timeout }, function (err, res, body) {
    if (err || !res || res.statusCode >= 400) {
      var statusCode = res ? res.statusCode : 0,
          statusMessage = res ? res.statusMessage : 'Unspecified error (likely a timeout)';
      if (statusCode === 404) return cb(new Error('Not found on CrossRef: \'' + endpoint + path + '\''));
      var msg = err && err.message ? err.message : statusMessage;
      return cb(new Error('CrossRef error: [' + statusCode + '] ' + msg));
    }
    if ((typeof body === 'undefined' ? 'undefined' : _typeof(body)) !== 'object') return cb(new Error('CrossRef response was not JSON: ' + body));
    if (!body.status) return cb(new Error('Malformed CrossRef response: no `status` field.'));
    if (body.status !== 'ok') return cb(new Error('CrossRef error: ' + body.status));
    cb(null, body.message);
  });
}

// make a method that just returns the one item
function item(urlTmpl) {
  return function (param, cb) {
    return GET(urlTmpl.replace('{param}', param), cb);
  };
}

// backend for list requests
function listRequest(path) {
  var options = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : {};
  var cb = arguments[2];

  if (typeof options === 'function') {
    cb = options;
    options = {};
  }
  // serialise options
  var opts = [];
  for (var k in options) {
    // The whole URL *minus* the scheme and "://" (for whatever benighted reason) has to be at most
    // 4096 characters long. Taking the extra bloat that `encodeURIComponent()` adds we truncate the
    // query to 2000 chars. We could be more precise and regenerate the URL until we reach as close
    // as possible to 4096, but frankly if you're searching for a string longer than 2000 characters
    // you're probably doing something wrong.
    if (k === 'query') {
      if (options.query.length > 2000) options.query = options.query.substr(0, 2000);
      opts.push('query=' + encodeURIComponent(options.query));
    } else if (k === 'filter') {
      (function () {
        var filts = [];

        var _loop = function _loop(f) {
          if (Array.isArray(options.filter[f])) {
            options.filter[f].forEach(function (val) {
              filts.push(f + ':' + val);
            });
          } else {
            filts.push(f + ':' + options.filter[f]);
          }
        };

        for (var f in options.filter) {
          _loop(f);
        }
        opts.push('filter=' + filts.join(','));
      })();
    } else if (k === 'facet' && options.facet) opts.push('facet=t');else opts.push(k + '=' + options[k]);
  }
  if (opts.length) path += '?' + opts.join('&');
  return GET(path, function (err, msg) {
    if (err) return cb(err);
    var objects = msg.items;
    delete msg.items;
    var nextOffset = 0;
    var isDone = false;
    var nextOptions = void 0;
    // /types is a list but it does not behave like the other lists
    // Once again the science.ai League of JStice saves the day papering over inconsistency!
    if (msg['items-per-page'] && msg.query) {
      nextOffset = msg.query['start-index'] + msg['items-per-page'];
      if (nextOffset > msg['total-results']) isDone = true;
      nextOptions = (0, _assign2.default)({}, options, { offset: nextOffset });
    } else {
      isDone = true;
      nextOptions = (0, _assign2.default)({}, options);
    }
    cb(null, objects, nextOptions, isDone, msg);
  });
}

// make a method that returns a list that can be
function list(path) {
  return function (options, cb) {
    return listRequest(path, options, cb);
  };
}
function itemList(urlTmpl) {
  return function (param, options, cb) {
    return listRequest(urlTmpl.replace('{param}', param), options, cb);
  };
}

// Actual API
// /works/{doi} 	returns metadata for the specified CrossRef DOI.
// /funders/{funder_id} 	returns metadata for specified funder and its suborganizations
// /prefixes/{owner_prefix} 	returns metadata for the DOI owner prefix
// /members/{member_id} 	returns metadata for a CrossRef member
// /types/{type_id} 	returns information about a metadata work type
// /journals/{issn} 	returns information about a journal with the given ISSN
var work = exports.work = item('works/{param}');
var funder = exports.funder = item('funders/{param}');
var prefix = exports.prefix = item('prefixes/{param}');
var member = exports.member = item('members/{param}');
var type = exports.type = item('types/{param}');
var journal = exports.journal = item('journals/{param}');

// /funders/{funder_id}/works 	returns list of works associated with the specified funder_id
// /types/{type_id}/works 	returns list of works of type type
// /prefixes/{owner_prefix}/works 	returns list of works associated with specified owner_prefix
// /members/{member_id}/works 	returns list of works associated with a CrossRef member
//                                  (deposited by a CrossRef member)
// /journals/{issn}/works 	returns a list of works in the given journal
var funderWorks = exports.funderWorks = itemList('funders/{param}/works');
var prefixWorks = exports.prefixWorks = itemList('prefixes/{param}/works');
var memberWorks = exports.memberWorks = itemList('members/{param}/works');
var journalWorks = exports.journalWorks = itemList('journals/{param}/works');

// /works 	returns a list of all works (journal articles, conference proceedings, books,
//                components, etc), 20 per page
// /funders 	returns a list of all funders in the FundRef Registry
// /members 	returns a list of all CrossRef members (mostly publishers)
// /types 	returns a list of valid work types
// /licenses 	return a list of licenses applied to works in CrossRef metadata
// /journals 	return a list of journals in the CrossRef database
var works = exports.works = list('works');
var funders = exports.funders = list('funders');
var members = exports.members = list('members');
var types = exports.types = list('types');
var licenses = exports.licenses = list('licenses');
var journals = exports.journals = list('journals');

// everything in one big ball
var CrossRef = {
  work: work,
  funder: funder,
  prefix: prefix,
  member: member,
  type: type,
  journal: journal,
  funderWorks: funderWorks,
  prefixWorks: prefixWorks,
  memberWorks: memberWorks,
  journalWorks: journalWorks,
  works: works,
  funders: funders,
  members: members,
  types: types,
  licenses: licenses,
  journals: journals
};
exports.default = CrossRef;