Load a large json into memory as javascript object

run-in-console.js

// from here: https://developer.mozilla.org/en-US/docs/Learn/JavaScript/Objects/JSON
var request = new XMLHttpRequest();
request.open('GET', 'http://localhost:8888/test.json')
request.responseType = 'json';
// request.onload = function() {
//     var data = request.response;
// }
request.send()
var data = request.response
// now you can do like
console.log(data.properties.firstname.value)

simple-cors-http-server.py

#!/usr/bin/env python3
# put test.json in same directory
from http.server import SimpleHTTPRequestHandler
from http.server import HTTPServer, test
import sys

class CORSRequestHandler (SimpleHTTPRequestHandler):
    def end_headers (self):
        self.send_header('Access-Control-Allow-Origin', '*')
        SimpleHTTPRequestHandler.end_headers(self)

if __name__ == '__main__':
    test(CORSRequestHandler, HTTPServer, port=int(sys.argv[1]) if len(sys.argv) > 1 else 8888)