REST Endpoint GeoJSON Demo

JSON, or Javascript Object Notation, has long been a common format for modern web applications using AJAX methodologies to dynamically display data. Recent years have seen an extension of this format into geography, called GeoJSON, providing web developers with a lightweight, open format that is easily parsed by Javascript and shown on simple maps. The format proved so popular that in 2014 Google Maps began supporting it, as did Esri in ArcGIS Online (AGOL) REST endpoints. (Here's an example.) As of version 10.4, you can request GeoJSON as a format from Esri services authored in ArcGIS Server. If you're working with an Esri-flavored endpoint that is older than that, you can leverage open Javascript libraries such as this one from Terraformer to convert their original version of JSON-with-geometry to GeoJSON.

Below we take this in a few directions. First, we utilize data from the USGS's Wind Turbine Database, which has a non-Esri API, but also an ArcGIS Server endpoint. Then, with some help from Lyzi Diamond and a plugin from Calvin Metcalf, we add that dataset with a bounding-box query of the layer, setting the output format to GeoJSON. (You'll only find this format in the HTML query form if it's available.)

All this is overlain on the Esri imagery web map tile service. If you zoom in on some of the records, you will usually see the wind turbine!