title: Easy way to determine if a point is in a polygon using Google Cloud Functions
body: <p>I have a collection of polygons (GeoJSON) within a Google Firestore collection.</p>
  
  <p>For a given lat/lng coordinate how can I determine which polygons would contain it?</p>
  
  <p>I have used Leaflet, and Mapbox to solve a similar problem for a front end solution but never for a backend. Other NoSQL databases can perform this search natively but I cannot determine if Firestore can as well.</p>
  
  <p>Hopefully, there is a relatively lightweight way of doing this search.</p>
  
  <p>Thanks for your input!</p>