<commit_before>---
title: L.esri.Layers.HeatMapFeatureLayer
layout: documentation.hbs
---

# {{page.data.title}}

`L.esri.Layers.HeatMapFeatureLayer` provides integration for Feature Layers with the [Leaflet.heat plugin](https://github.com/Leaflet/Leaflet.heat). Because of the extra Dependency on Leaflet.heat we do not include `L.esri.Layers.HeatMapFeatureLayer` in the default build of Esri Leaflet. It lives in /dist/extras/heatmap-feature-layer.js. You will also need to include your own copy of the [Leaflet.heat plugin](https://github.com/Leaflet/Leaflet.heat).

More information about Feature Layers can be found in the [`L.esri.Layers.FeatureLayer` documentation]({{assets}}api-reference/layers/feature-layer.html).

### Constructor

<table>
    <thead>
        <tr>
            <th>Constructor</th>
            <th>Description</th>
        </tr>
    </thead>
    <tbody>
        <tr>
            <td><code class="nobr">new L.esri.Layers.HeatmapFeatureLayer({{{param 'String' 'key'}}}, {{{param 'Object' 'options'}}})</code><br><br><code class="nobr">L.esri.Layers.heatmapFeatureLayer({{{param 'String' 'key'}}}, {{{param 'Object' 'options'}}})</code><br><br><code class="nobr">new L.esri.HeatmapFeatureLayer({{{param 'String' 'key'}}}, {{{param 'Object' 'options'}}})</code><br><br><code class="nobr">L.esri.heatmapFeatureLayer({{{param 'String' 'key'}}}, {{{param 'Object' 'options'}}})</code></td>
            <td><code>url</code> should be the URL to the Feature Layer.</td>
        </tr>
    </tbody>
</table>
### Options

<table>
    <thead>
        <tr>
            <th>Option</th>
            <th>Type</th>
            <th>Description</th>
        </tr>
    </thead>
    <tbody>
        <tr>
            <td><code>where</code></td>
            <td><code>String</code></td
            <td>A server side expression that will be evaluated to filter features. By default this will include all features in a service.</td>
        </tr>
        <tr>
            <td><code>fields</code></td>
            <td><code>Array</code></td>
            <td>An array of metadata names to pull from the service. Includes all fields by default.</td>
        </tr>
        <tr>
            <td><code>from</code></td><commit_msg>Change param name `key` to `url`<commit_after>---
title: L.esri.Layers.HeatMapFeatureLayer
layout: documentation.hbs
---

# {{page.data.title}}

`L.esri.Layers.HeatMapFeatureLayer` provides integration for Feature Layers with the [Leaflet.heat plugin](https://github.com/Leaflet/Leaflet.heat). Because of the extra Dependency on Leaflet.heat we do not include `L.esri.Layers.HeatMapFeatureLayer` in the default build of Esri Leaflet. It lives in /dist/extras/heatmap-feature-layer.js. You will also need to include your own copy of the [Leaflet.heat plugin](https://github.com/Leaflet/Leaflet.heat).

More information about Feature Layers can be found in the [`L.esri.Layers.FeatureLayer` documentation]({{assets}}api-reference/layers/feature-layer.html).

### Constructor

<table>
    <thead>
        <tr>
            <th>Constructor</th>
            <th>Description</th>
        </tr>
    </thead>
    <tbody>
        <tr>
            <td><code class="nobr">new L.esri.Layers.HeatmapFeatureLayer({{{param 'String' 'url'}}}, {{{param 'Object' 'options'}}})</code><br><br><code class="nobr">L.esri.Layers.heatmapFeatureLayer({{{param 'String' 'url'}}}, {{{param 'Object' 'options'}}})</code><br><br><code class="nobr">new L.esri.HeatmapFeatureLayer({{{param 'String' 'url'}}}, {{{param 'Object' 'options'}}})</code><br><br><code class="nobr">L.esri.heatmapFeatureLayer({{{param 'String' 'url'}}}, {{{param 'Object' 'options'}}})</code></td>
            <td><code>url</code> should be the URL to the Feature Layer.</td>
        </tr>
    </tbody>
</table>
### Options

<table>
    <thead>
        <tr>
            <th>Option</th>
            <th>Type</th>
            <th>Description</th>
        </tr>
    </thead>
    <tbody>
        <tr>
            <td><code>where</code></td>
            <td><code>String</code></td
            <td>A server side expression that will be evaluated to filter features. By default this will include all features in a service.</td>
        </tr>
        <tr>
            <td><code>fields</code></td>
            <td><code>Array</code></td>
            <td>An array of metadata names to pull from the service. Includes all fields by default.</td>
        </tr>
        <tr>
            <td><code>from</code></td>
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