lizard-javascript-api/lib/utils.js

Library to interact with lizard assets, rasters and timeseries.

'use strict';

var _isomorphicFetch = require('isomorphic-fetch');

var _isomorphicFetch2 = _interopRequireDefault(_isomorphicFetch);

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

var baseUrl = function () {
  var absoluteBase = 'http://demo.lizard.net';

  if (typeof window !== 'undefined') {
    var protocol = window && window.location.protocol;

    var host = window && window.location.host;

    var port = window && window.location.port;

    absoluteBase = protocol + '://' + host + ':' + port;
  }
  return absoluteBase;
}();

var fetchItem = function fetchItem(entity, id) {
  var plural = entity + 's';

  var request = new Request(baseUrl + '/api/v2/' + plural + '/' + id, {
    credentials: 'same-origin'
  });

  return (0, _isomorphicFetch2.default)(request).then(function (response) {
    return response.json();
  });
};

/**
 * Stringifies a GeoJSON object into WKT
 */
var geomToWkt = function geomToWkt(gj) {
  if (gj.type === 'Feature') {
    gj = gj.geometry;
  }

  function wrapParens(s) {
    return '(' + s + ')';
  }

  function pairWKT(c) {
    return c.join(' ');
  }

  function ringWKT(r) {
    return r.map(pairWKT).join(', ');
  }

  function ringsWKT(r) {
    return r.map(ringWKT).map(wrapParens).join(', ');
  }

  function multiRingsWKT(r) {
    return r.map(ringsWKT).map(wrapParens).join(', ');
  }

  switch (gj.type) {
    case 'Point':
      return 'POINT (' + pairWKT(gj.coordinates) + ')';
    case 'LineString':
      return 'LINESTRING (' + ringWKT(gj.coordinates) + ')';
    case 'Polygon':
      return 'POLYGON (' + ringsWKT(gj.coordinates) + ')';
    case 'MultiPoint':
      return 'MULTIPOINT (' + ringWKT(gj.coordinates) + ')';
    case 'MultiPolygon':
      return 'MULTIPOLYGON (' + multiRingsWKT(gj.coordinates) + ')';
    case 'MultiLineString':
      return 'MULTILINESTRING (' + ringsWKT(gj.coordinates) + ')';
    case 'GeometryCollection':
      return 'GEOMETRYCOLLECTION (' + gj.geometries.map(undefined.geomToWkt).join(', ') + ')';
    default:
      throw new Error('geomToWkt requires a valid GeoJSON Feature or geometry object as input');
  }
};

module.exports = { fetchItem: fetchItem, geomToWkt: geomToWkt, baseUrl: baseUrl };