How to add a GeoJSON layer in GraphHopper? - leaflet

Question

I have a GeoJSON file containing POIs that I'd like to be able to display within a separate GraphHopper layer. After several tries and search over internet, I just can't manage to get a way to do it.
This is a sample of the GeoJSON file (I checked the whole file with JSON validator and it was OK).
{"type": "Feature",
"properties": {
"fee": "no",
"bicycle_parking": "anchors",
"ref": "PVNAN23",
"address": "Rue Gabriel Goudy 44200 Nantes",
"name": "Pirmil P+R",
"capacity": "24",
"park_ride": "yes",
"amenity": "bicycle_parking",
"covered": "yes"
},
"geometry": {"type": "Point", "coordinates": [-1.5406709, 47.1960031]}},
{"type": "Feature",
"properties": {
"bicycle_parking": "stands",
"addr:postcode": "44000",
"addr:country": "FR",
"name": "Madeleine",
"capacity": "6",
"amenity": "bicycle_parking",
"addr:street": "chaussée de la Madeleine",
"note": "vérifié",
"addr:city": "Nantes",
"covered": "no",
"addr:housenumber": "35"
},
"geometry": {"type": "Point", "coordinates": [-1.55076671448, 47.21000114109]}}
]}
I tried what is explained in How to load external geojson file into leaflet map but I cannot get it working.

Answer 1

If your JSON is valid that doesn't mean you're working with a valid GeoJSON object. For instance: {"foo": "bar"} is perfectly valid JSON but in no way a valid GeoJSON object. L.GeoJSON, leaflet's GeoJSON layer expects a FeatureCollection or an array containing Features.
A valid FeatureCollection:
{
"type": "FeatureCollection",
"features": [{
"type": "Feature",
"properties": {
"id": 1
},
"geometry": {
"type": "Point",
"coordinates": [0,0]
}
},{
"type": "Feature",
"properties": {
"id": 2
},
"geometry": {
"type": "Point",
"coordinates": [1,1]
}
}]
}
Or just the array with features:
[{
"type": "Feature",
"properties": {
"id": 1
},
"geometry": {
"type": "Point",
"coordinates": [0,0]
}
},{
"type": "Feature",
"properties": {
"id": 2
},
"geometry": {
"type": "Point",
"coordinates": [1,1]
}
}]
(Note that just an array of features isn't a valid GeoJSON object but Leaflet will handle it without problems)
To load these into a L.GeoJson layer you'll need to make them available in your script. You could simple declare the object before you create the layer. For example:
// Declare GeoJSON object
var geojson = {
type: "FeatureCollection",
features: [
// Features here
]
}
// Create a new GeoJSON layer with geojson object
// And add to map (assuming your map instance is assigned to "map")
var layer = new L.GeoJSON(geojson).addTo(map);
But that will become quite a mess when you've got lots of features and it's always better to keep your logic and data separated so you should put your data object in a separate file. So let's say you've got the object stored in a file called "geo.json", then you can load the file with XHR/AJAX solution of your choice. I'm using jQuery in the following example:
// Fetch geo.json file and assign the data to geojson variable
$.getJSON('geo.json', function (geojson) {
// Create a new GeoJSON layer with GeoJSON object
// And add to map (assuming your map instance is assigned to "map")
var layer = new L.GeoJSON(geojson).addTo(map);
});
Here a working example on Plunker: http://plnkr.co/edit/Mh8p4F?p=preview