const GeoJSON = require('geojson'); const extent = require('@mapbox/geojson-extent'); const logger = require('pelias-logger').get('geojsonify'); const collectDetails = require('./geojsonify_place_details'); const _ = require('lodash'); const Document = require('pelias-model').Document; const field = require('./fieldValue'); function geojsonifyPlaces( params, docs ){ // flatten & expand data for geojson conversion const geodata = docs .filter(doc => { if (!_.has(doc, 'center_point')) { logger.warn('No doc or center_point property'); return false; } else { return true; } }) .map(geojsonifyPlace.bind(null, params)); // get all the bounding_box corners as well as single points // to be used for computing the overall bounding_box for the FeatureCollection const extentPoints = extractExtentPoints(geodata); // convert to geojson const geojson = GeoJSON.parse( geodata, { Point: ['lat', 'lng'] }); const geojsonExtentPoints = GeoJSON.parse( extentPoints, { Point: ['lat', 'lng'] }); // to insert the bbox property at the top level of each feature, it must be done separately after // initial geojson construction is finished addBBoxPerFeature(geojson); // bounding box calculations computeBBox(geojson, geojsonExtentPoints); return geojson; } function geojsonifyPlace(params, place) { // setup the base doc const doc = { id: place._id, gid: new Document(place.source, place.layer, place._id).getGid(), layer: place.layer, source: place.source, source_id: place.source_id, bounding_box: place.bounding_box, lat: parseFloat(place.center_point.lat), lng: parseFloat(place.center_point.lon) }; // assign name, logging a warning if it doesn't exist if (_.has(place, 'name.default')) { doc.name = field.getStringValue(place.name.default); } else { logger.warn(`doc ${doc.gid} does not contain name.default`); } // assign all the details info into the doc Object.assign(doc, collectDetails(params, place)); return doc; } /** * Add bounding box * * @param {object} geojson */ function addBBoxPerFeature(geojson) { geojson.features.forEach(feature => { if (feature.properties.bounding_box) { feature.bbox = [ feature.properties.bounding_box.min_lon, feature.properties.bounding_box.min_lat, feature.properties.bounding_box.max_lon, feature.properties.bounding_box.max_lat ]; } delete feature.properties.bounding_box; }); } /** * Collect all points from the geodata. * If an item is a single point, just use that. * If an item has a bounding box, add two corners of the box as individual points. * * @param {Array} geodata * @returns {Array} */ function extractExtentPoints(geodata) { return geodata.reduce((extentPoints, place) => { // if there's a bounding_box, use the LL/UR for the extent if (place.bounding_box) { extentPoints.push({ lng: place.bounding_box.min_lon, lat: place.bounding_box.min_lat }); extentPoints.push({ lng: place.bounding_box.max_lon, lat: place.bounding_box.max_lat }); } else { // otherwise, use the point for the extent extentPoints.push({ lng: place.lng, lat: place.lat }); } return extentPoints; }, []); } /** * Compute bbox that encompasses all features in the result set. * Set bbox property on the geojson object. * * @param {object} geojson */ function computeBBox(geojson, geojsonExtentPoints) { // @note: extent() sometimes throws Errors for unusual data // eg: https://github.com/pelias/pelias/issues/84 try { var bbox = extent( geojsonExtentPoints ); if( !!bbox ){ geojson.bbox = bbox; } } catch( e ){ console.error( 'bbox error', e.message, e.stack ); console.error( 'geojson', JSON.stringify( geojsonExtentPoints, null, 2 ) ); } } module.exports = geojsonifyPlaces;