Blind / Passive Approach

• Get request IP:
  • HTTP: https://expressjs.com/en/4x/api.html#req.ip
  • WebSocket: https://github.com/socketio/engine.io/blob/49362abcd0c176ed0f8621bc70820a8adf9859b2/lib/socket.js#L33-L38
• Countries and cities dataset:
  • https://dev.maxmind.com/geoip/geoip2/geolite2/
• Reader:
  • https://www.npmjs.com/package/maxmind
• City to coordinates:
  • https://www.npmjs.com/package/all-the-cities
• Calculate distance:
  • https://www.npmjs.com/package/spherical-geometry-js
  • https://github.com/mapbox/cheap-ruler

var x = cheapRuler(lat1, 'kilometers');
x.distance([lat1, long1], [lat2, long2]);

Proactive Approach

• https://developer.mozilla.org/en-US/docs/Web/API/Geolocation/getCurrentPosition

var options = {
  enableHighAccuracy: true,
  timeout: 5000,
  maximumAge: 0
};
function success(pos) {
  var crd = pos.coords;
  console.log('Your current position is:');
  console.log(`Latitude : ${crd.latitude}`);
  console.log(`Longitude: ${crd.longitude}`);
  console.log(`More or less ${crd.accuracy} meters.`);
}
function error(err) {
  console.warn(`ERROR(${err.code}): ${err.message}`);
}
navigator.geolocation.getCurrentPosition(success, error, options);

• https://github.com/google/open-location-code/tree/master/js

OpenLocationCode.encode(lat, long)
OpenLocationCode.decode(lat, long)

WebSockets

• https://github.com/socketio/engine.io-client
• https://github.com/socketio/engine.io

Visualization

• d3 geo
  • https://www.npmjs.com/package/d3-geo
• Map
  • https://bl.ocks.org/mbostock/3757119
• Map Arcs
  • https://stackoverflow.com/a/39650848
• It's like Netflix's viszeral, but focused on worldmap instead.
  • https://github.com/Netflix/vizceral
• Nodes are based on coordinates of cities
• Nodes are color-based
  • https://github.com/gka/chroma.js
• Nodes have animations
  • Connection status
  • Activity between nodes
  • http://duspviz.mit.edu/d3-workshop/transitions-animation/