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var GeoJSON = require('geojson');
var extent = require('geojson-extent');
var logger = require('pelias-logger').get('api');
var type_mapping = require('./type_mapping');
var _ = require('lodash');
var addDetails = require('./geojsonify_place_details');
var addMetaData = require('./geojsonify_meta_data');
function geojsonifyPlaces( params, docs ){
// flatten & expand data for geojson conversion
var geodata = docs
.map(geojsonifyPlace.bind(null, params))
.filter( function( doc ){
return !!doc;
});
// get all the bounding_box corners as well as single points
// to be used for computing the overall bounding_box for the FeatureCollection
var extentPoints = extractExtentPoints(geodata);
// convert to geojson
var geojson = GeoJSON.parse( geodata, { Point: ['lat', 'lng'] });
var 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) {
// something went very wrong
if( !place || !place.hasOwnProperty( 'center_point' ) ) {
return warning('No doc or center_point property');
}
var output = {};
addMetaData(place, output);
addName(place, output);
addDetails(params, place, output);
// map center_point for GeoJSON to work properly
// these should not show up in the final feature properties
output.lat = parseFloat(place.center_point.lat);
output.lng = parseFloat(place.center_point.lon);
return output;
}
10 years ago
/**
* Validate and add name property
*
* @param {object} src
* @param {object} dst
*/
function addName(src, dst) {
// map name
if( !src.name || !src.name.default ) { return warning(src); }
dst.name = src.name.default;
}
/**
* Add bounding box
*
* @param {object} geojson
*/
function addBBoxPerFeature(geojson) {
geojson.features.forEach(function (feature) {
if (!feature.properties.hasOwnProperty('bounding_box')) {
return;
}
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) {
var extentPoints = [];
geodata.forEach(function (place) {
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 {
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 ) );
}
}
/**
* emit a warning if the doc format is invalid
*
* @note: if you see this error, fix it ASAP!
*/
function warning( doc ) {
console.error( 'error: invalid doc', __filename, doc);
return false; // remove offending doc from results
}
module.exports = geojsonifyPlaces;