Leaflet create GeoJSON polygon layer from Turf buffer on GeoJSON point layer while keeping the attributes

Question

I have Leaflet GeoJSON point layer that I buffer with turf and add to the map. The code works well but I want to add the point attributes to the polygon layer but I am unsure of how to do to that. Anyone can run this code in the console if they have a an app with Leaflet and turf

var all_day=L.layerGroup();
$.getJSON("https://earthquake.usgs.gov/earthquakes/feed/v1.0/summary/all_day.geojson", function(data) {
        L.geoJSON(data, {
                onEachFeature: function(feature,layer){
                            layer.bindPopup('<b>Magnitude</b>= '+feature.properties.mag+'<br>'+
                                            '<b>Place</b>= '+feature.properties.place+'<br>');
                            var magnitude=feature.properties.mag;
                            var place=feature.properties.place;

                            var buffed=turf.buffer(feature.geometry,magnitude*10)

                            L.geoJSON(buffed, {
                              onEachFeature: function(feature,layer){
                                layer.bindPopup('<b>Magnitude</b>= '+magnitude+'<br>'+
                                            '<b>Place</b>= '+place+'<br>')
                              }}).addTo(all_day);
                                           
                        }
                    }).addTo(all_day);
});
all_day.addTo(map);

I saw something like this answer https://stackoverflow.com/questions/35760126/leaflet-draw-not-taking-properties-when-converting-featuregroup-to-geojson/35819611#35819611 but it didn't work for me and its kind of clunky.

Answer 1

All you have to do after you create buffed feature is to assign to it the properties from parent feature:

buffed.properties = feature.properties;

Code could then look something like this:

L.geoJSON(data, {
  onEachFeature: function(feature,layer) {
    layer.bindPopup('<b>Magnitude</b>= ' + feature.properties.mag + '<br>'+
                    '<b>Place</b>= ' + feature.properties.place + '<br>');
    var buffed = turf.buffer(feature.geometry, feature.properties.mag * 10);
    buffed.properties = feature.properties;
    L.geoJSON(buffed, {
      onEachFeature: function(feature,layer) {
        layer.bindPopup('<b>Magnitude</b>= ' + feature.properties.mag + '<br>'+
                        '<b>Place</b>= ' + feature.properties.place + '<br>');
      }
    }).addTo(all_day);
  }
}).addTo(all_day);