Esri Leaflet identify() only on added layer from MapService

Question

I try to identify features only from the wastepit layer. In this example I am adding two layers: wells and wastepit. I am only calling the identify function on the wastepit layer but I still get features if I press on a location for a well? Please see the codepen for live example. How can I do so I am only get the featureInfo from the wastepit layer? I dont understand why I in fact get feature from all (8) layers in the MapService?

    wells = L.esri.dynamicMapLayer({
            url: url,
            layers: [0]
          }).addTo(map);

pipe = L.esri.dynamicMapLayer({
                url: url,
                layers: [4]
              }).addTo(map);

wastepit = L.esri.dynamicMapLayer({
            url: url,
            layers: [5]
          }).addTo(map);

function getFeatureInfo(e) {
  wastepit.identify()
    .on(map)
    .at(e.latlng)
    .run(function(error, featureCollection){

https://codepen.io/GitMorin/pen/MLQvdM?editors=0010

Answer 1

By default L.esri.IdentifyFeatures queries all the layers in the map service.

https://github.com/Esri/esri-leaflet/blob/v2.2.3/src/Tasks/IdentifyFeatures.js#L20

From the looks of your codepen, it appears you already found out that you can customize this behavior by supplying an alternative strategy and any combination of layers you want.

 .layers('all:5')

It's worth noting that dynamicMapLayer.bindPopup() passes through options set on the layer automatically.

It's also worth noting that its sub-optimal to add multiple individual dynamicMapLayers to the same map for each individual layer when you can ask the service to draw as many (or few) as you want all at once.