layer/layerRec/wmsFC.js

  1. 'use strict';
  3. const basicFC = require('./basicFC.js')();
  5. /**
  6.  * Searches for a layer title defined by a wms.
  7.  * @function getWMSLayerTitle
  8.  * @private
  9.  * @param  {Object} wmsLayer     esri layer object for the wms
  10.  * @param  {String} wmsLayerId   layers id as defined in the wms (i.e. not wmsLayer.id)
  11.  * @return {String}              layer title as defined on the service, '' if no title defined
  12.  */
  13. function getWMSLayerTitle(wmsLayer, wmsLayerId) {
  14.     // TEST STATUS none
  15.     // TODO move this to ogc.js module?
  17.     // crawl esri layerInfos (which is a nested structure),
  18.     // returns sublayer that has matching id or null if not found.
  19.     // written as function to allow recursion
  20.     const crawlSubLayers = (subLayerInfos, wmsLayerId) => {
  21.         let targetEntry = null;
  23.         // we use .some to allow the search to stop when we find something
  24.         subLayerInfos.some(layerInfo => {
  25.             // wms ids are stored in .name
  26.             if (layerInfo.name === wmsLayerId) {
  27.                 // found it. save it and exit the search
  28.                 targetEntry = layerInfo;
  29.                 return true;
  30.             } else if (layerInfo.subLayers) {
  31.                 // search children. if in children, will exit search, else will continue
  32.                 return crawlSubLayers(layerInfo.subLayers, wmsLayerId);
  33.             } else {
  34.                 // continue search
  35.                 return false;
  36.             }
  37.         });
  39.         return targetEntry;
  40.     };
  42.     // init search on root layerInfos, then process result
  43.     const match = crawlSubLayers(wmsLayer.layerInfos, wmsLayerId);
  44.     if (match && match.title) {
  45.         return match.title;
  46.     } else {
  47.         return ''; // falsy!
  48.     }
  49. }
  51. /**
  52.  * @class WmsFC
  53.  */
  54. class WmsFC extends basicFC.BasicFC {
  56.     // this will actively download / refresh the internal symbology
  57.     loadSymbology () {
  58.         const configLayerEntries =  this._parent.config.layerEntries;
  59.         const gApi = this._parent._apiRef;
  60.         const legendArray = gApi.layer.ogc
  61.             .getLegendUrls(this._parent._layer, configLayerEntries.map(le => le.id))
  62.             .map((imageUri, idx) => {
  64.                 const symbologyItem = {
  65.                     name: null,
  66.                     svgcode: null
  67.                 };
  69.                 // config specified name || server specified name || config id
  70.                 const name = configLayerEntries[idx].name ||
  71.                     getWMSLayerTitle(this._parent._layer, configLayerEntries[idx].id) ||
  72.                     configLayerEntries[idx].id;
  74.                 gApi.symbology.generateWMSSymbology(name, imageUri).then(data => {
  75.                     symbologyItem.name = data.name;
  76.                     symbologyItem.svgcode = data.svgcode;
  77.                 });
  79.                 return symbologyItem;
  80.             });
  81.         this.symbology = legendArray;
  82.         return Promise.resolve();
  83.     }
  84. }
  86. module.exports = () => ({
  87.     WmsFC
  88. });