@geogirafe/lib-geoportal/components/advancedfilter/layercsvexporter.js

GeoGirafe is a flexible application to build online geoportals.

import LayerWms from '../../models/layers/layerwms.js';
import SelectionParam from '../../models/selectionparam.js';
import { removeUnwantedOlParams } from '../../tools/utils/olutils.js';
import { WKT } from 'ol/format.js';
import CsvManager from '../../tools/export/csvmanager.js';
import ColumnAliasHelper from '../../tools/utils/aliases.js';
class LayerCsvExporter {
    context;
    csvManager;
    columnAliasHelper;
    wktFormat = new WKT();
    WKT_DECIMALS = 2;
    csvContentTruncated = false;
    constructor(context) {
        this.context = context;
        this.csvManager = new CsvManager(this.context);
        this.columnAliasHelper = new ColumnAliasHelper(this.context.stateManager);
    }
    async createCsvFile(layer) {
        this.csvContentTruncated = false;
        if (!layer) {
            return;
        }
        if (layer instanceof LayerWms) {
            const features = await this.requestFeatures(layer);
            const { data, columnDefs } = this.featuresToColumnData(features, layer.name);
            const layerName = this.context.i18nManager.getTranslation(layer.name);
            this.csvManager.startDownload(data, columnDefs, `${layerName}-filter-result.csv`);
        }
    }
    async requestFeatures(layer) {
        // Create a selection param object that defines the map max extent but nothing more.
        //  Any layer filter will be applied in the client automatically.
        const projection = this.context.mapManager.getMap().getView().getProjection();
        let extent = this.context.configManager.Config.map.maxExtent?.split(',').map(Number);
        extent ??= projection.getExtent();
        const selectionParam = new SelectionParam(layer.ogcServer, [layer], projection.getCode(), extent);
        if (layer.wfsQueryable) {
            const client = this.context.wfsManager.getClient(layer.ogcServer);
            return await client.getFeature(selectionParam).then((features) => {
                if (features.length === client.maxFeatures) {
                    this.csvContentTruncated = true;
                }
                return features;
            });
        }
        else {
            return [];
        }
    }
    featuresToColumnData(features, layerName, includeGeometry = true) {
        const data = features.map((feature) => {
            const properties = removeUnwantedOlParams(feature, false);
            const geometry = feature.getGeometry();
            if (includeGeometry && geometry) {
                properties[feature.getGeometryName()] = this.wktFormat.writeGeometry(geometry, {
                    decimals: this.WKT_DECIMALS
                });
            }
            return properties;
        });
        let columnDefs = [];
        if (data.length > 0) {
            columnDefs = Object.keys(data[0]).map((columnName) => {
                return {
                    name: this.columnAliasHelper.getColumnAlias(layerName, columnName)
                };
            });
        }
        return { data, columnDefs };
    }
}
export default LayerCsvExporter;