# FeatureIdentifier

> **FeatureIdentifier** = `object`

Defined in: [style/style.ts:79](<https://github.com/maplibre/maplibre-gl-js/blob/538a7680ab16d5cf5a6564ee0ce72a11be14d142/src/style/style.ts#L79>)

A feature identifier that is bound to a source

## Properties

### id?

> `optional` **id?**: `string` | `number`

Defined in: [style/style.ts:83](<https://github.com/maplibre/maplibre-gl-js/blob/538a7680ab16d5cf5a6564ee0ce72a11be14d142/src/style/style.ts#L83>)

Unique id of the feature.

---

### source

> **source**: `string`

Defined in: [style/style.ts:87](<https://github.com/maplibre/maplibre-gl-js/blob/538a7680ab16d5cf5a6564ee0ce72a11be14d142/src/style/style.ts#L87>)

The id of the vector or GeoJSON source for the feature.

---

### sourceLayer?

> `optional` **sourceLayer?**: `string`

Defined in: [style/style.ts:91](<https://github.com/maplibre/maplibre-gl-js/blob/538a7680ab16d5cf5a6564ee0ce72a11be14d142/src/style/style.ts#L91>)

*For vector tile sources, `sourceLayer` is required.*