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var GeoJSON = require('geojson'),
extent = require('geojson-extent'),
labelGenerator = require('./labelGenerator'),
logger = require('pelias-logger').get('api'),
type_mapping = require('./type_mapping'),
_ = require('lodash');
// Properties to be copied
var DETAILS_PROPS = [
'housenumber',
'street',
'postalcode',
'confidence',
'distance',
'country',
'country_id',
'country_a',
'macroregion',
'macroregion_id',
'macroregion_a',
'region',
'region_id',
'region_a',
'macrocounty',
'macrocounty_id',
'macrocounty_a',
'county',
'county_id',
'county_a',
'localadmin',
'localadmin_id',
'localadmin_a',
'locality',
'locality_id',
'locality_a',
'neighbourhood',
'neighbourhood_id'
];
function lookupSource(src) {
return src.source;
}
function lookupLayer(src) {
return src.layer;
}
function geojsonifyPlaces( docs ){
// flatten & expand data for geojson conversion
var geodata = docs
.map(geojsonifyPlace)
.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(place) {
// something went very wrong
if( !place || !place.hasOwnProperty( 'center_point' ) ) {
return warning('No doc or center_point property');
}
var output = {};
addMetaData(place, output);
addDetails(place, output);
addLabel(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
/**
* Add details properties
*
* @param {object} src
* @param {object} dst
*/
function addDetails(src, dst) {
// map name
if( !src.name || !src.name.default ) { return warning(src); }
dst.name = src.name.default;
copyProperties(src, DETAILS_PROPS, dst);
}
/**
* Add region-specific label string
*
* @param {object} src
* @param {object} dst
*/
function addLabel(src, dst) {
dst.label = labelGenerator(dst);
}
/**
* 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 ) );
}
}
/**
* Copy specified properties from source to dest.
* Ignore missing properties.
*
* @param {object} source
* @param {[]} props
* @param {object} dst
*/
function copyProperties( source, props, dst ) {
props.forEach( function ( prop ) {
if ( source.hasOwnProperty( prop ) ) {
// array value, take first item in array (at this time only used for admin values)
if (source[prop] instanceof Array) {
if (source[prop].length === 0) {
return;
}
if (source[prop][0]) {
dst[prop] = source[prop][0];
}
}
// simple value
else {
dst[prop] = source[prop];
}
}
});
}
/**
* Create a gid from a document
* @TODO modify all importers to create separate source and layer fields to remove mapping
*
* @param {object} src
*/
function makeGid(src) {
return lookupSource(src) + ':' + lookupLayer(src) + ':' + src._id;
}
/**
* Determine and set place id, type, and source
*
* @param {object} src
* @param {object} dst
*/
function addMetaData(src, dst) {
dst.id = src._id;
dst.gid = makeGid(src);
dst.layer = lookupLayer(src);
dst.source = lookupSource(src);
if (src.hasOwnProperty('bounding_box')) {
dst.bounding_box = src.bounding_box;
}
}
/**
* 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.search = geojsonifyPlaces;