Method getMapLayerExtent

src/openlayers/mapping/WebMap.js:4957–5014

* @private * @function WebMap.prototype.getMapLayerExtent * @description 获取mapboxstyle图层信息 * @param {Object} layerInfo 图层信息 * @returns {Object} 图层信息

(layerInfo)

   * @returns {Object}  图层信息
   */
  getMapLayerExtent(layerInfo) {
    const restMapMVTStr = '/tileFeature/vectorstyles.json?type=MapBox_GL&styleonly=true&tileURLTemplate=ZXY';
    let dataSource = layerInfo.dataSource;
    let url = dataSource.url;
    if (this.isRestMapMapboxStyle(layerInfo)) {
      url = url.replace(restMapMVTStr, '');
      url = this.getRequestUrl(url + '.json');
    }
    if (url.indexOf('/restjsr/') > -1 && !/\.json$/.test(url)) {
      url = this.getRequestUrl(url + '.json');
    } else {
      url = this.getRequestUrl(url);
    }

    let credential = layerInfo.credential;
    let credentialValue, keyfix;
    //携带令牌(restmap用的首字母大写，但是这里要用小写)
    if (credential) {
      keyfix = Object.keys(credential)[0];
      credentialValue = credential[keyfix];
      url = `${url}?${keyfix}=${credentialValue}`;
    }

    return FetchRequest.get(url, null, {
      withCredentials: this.isCredentail(url),
      withoutFormatSuffix: true,
      headers: {
        'Content-Type': 'application/json;chartset=uft-8'
      }
    })
      .then(function (response) {
        return response.json();
      })
      .then((result) => {
        layerInfo.visibleScales = result.visibleScales;
        layerInfo.coordUnit = result.coordUnit || 'METER';
        layerInfo.scale = result.scale;
        layerInfo.epsgCode = (result.prjCoordSys && result.prjCoordSys.epsgCode) || '3857';
        layerInfo.bounds = result.bounds || {
          top: 20037508.342789244,
          left: -20037508.342789244,
          bottom: -20037508.342789244,
          leftBottom: {
            x: -20037508.342789244,
            y: -20037508.342789244
          },
          right: 20037508.342789244,
          rightTop: {
            x: 20037508.342789244,
            y: 20037508.342789244
          }
        };
        return layerInfo;
      })
      .catch((error) => {
        throw error;
      });
  }