Example of Streaming Esri JSON to GeoJSON

index.js

const request = require('request')
const JSONStream = require('JSONStream')
const TerraformerArcGIS = require('terraformer-arcgis-parser')
const geojsonStream = require('geojson-stream')
const fs = require('fs')

const url = 'http://sjcgis.org/arcgis/rest/services/Polaris/Buildings/MapServer/0/query?outSR=4326&where=FID >= 20000 AND FID<=20175&f=json&outFields=*&geometry=&returnGeometry=true&geometryPrecision=10'

const featureStream = JSONStream.parse('features.*', convert)
const outFile = fs.createWriteStream('features.geojson')

request.get({url: url})
  .on('error', err => console.log('Error', err))
  .pipe(featureStream)
  .pipe(geojsonStream.stringify())
  .pipe(outFile)

function convert (feature) {
  const gj = {
    type: 'Feature',
    properties: feature.attributes,
    geometry: TerraformerArcGIS.parse(feature.geometry)
  }
  return gj
}