Redis GEOSEARCH for Nearest Driver Dispatch

Learn Redis GEOSEARCH for nearest driver dispatch: GEOADD courier GPS, radius query with WITHDIST, GEORADIUS vs GEOSEARCH, and a Node.js nearest-drivers API.

Redis GEOSEARCH is the command you use when you need the nearest drivers inside a map radius — without scanning MongoDB on every dispatch. For food delivery and on-demand marketplaces, that query is the heart of courier matching: given a restaurant (or dropoff) coordinate, return available drivers sorted by distance.

This tutorial is only about Redis geo for nearest driver dispatch: GEOADD, GEOSEARCH, and keeping the index limited to available couriers. No batching, sockets, or payments mixed in.

What is Redis GEOSEARCH?

Redis GEOSEARCH queries a Redis geo index (a sorted set of members with lon/lat) and returns members within a circle or box. With ASC, WITHDIST, and COUNT, you get a shortlist of the closest drivers — ideal for dispatch.

Why teams pick Redis for this instead of a full table scan:

• GPS pings write often; Redis handles high-frequency GEOADD updates in memory
• Radius reads stay O(log N) style lookups instead of loading every driver document
• The same pattern works for “drivers near restaurant” and “drivers near customer”

Courier GPS → GEOADD drivers:geo lng lat <driverId>
Restaurant ready → GEOSEARCH … BYRADIUS 5 km ASC WITHDIST COUNT 20
Result → nearest driver ids + distanceKm → offer job

GEOADD: index live driver locations

Before you can run Redis GEOSEARCH, drivers must exist in the geo key. Redis GEOADD stores longitude, latitude, and a member id (your driver ObjectId as a string).

Axis order is always longitude, then latitude (GeoJSON order). Mixing axes breaks every radius query.

Node.js — Redis GEOADD

await redis.geoAdd('drivers:geo', {
  longitude: lng,
  latitude: lat,
  member: String(driverId),
});

redis-cli

GEOADD drivers:geo 9.70 4.05 64f1a2b3c4d5e6f7a8b9c0d1

GEOSEARCH: nearest drivers by radius

This is the money command. Redis GEOSEARCH nearest drivers from a restaurant (or customer) point:

Node.js — Redis GEOSEARCH WITHDIST

const rows = await redis.geoSearchWith(
  'drivers:geo',
  { longitude: restaurantLng, latitude: restaurantLat },
  { radius: 5, unit: 'km' },
  ['WITHDIST'],
  { SORT: 'ASC', COUNT: 20 }
);
// [{ member: 'driverId', distance: '0.42' }, …]

redis-cli — GEOSEARCH nearest drivers

GEOSEARCH drivers:geo FROMLONLAT 9.70 4.05 BYRADIUS 5 km ASC WITHDIST COUNT 20

Map each hit to { driverId, distanceKm }. Redis solved proximity; your marketplace still owns who gets the offer.

GEORADIUS vs GEOSEARCH

Older docs and Stack Overflow answers still say Redis GEORADIUS. Redis 6.2+ recommends GEOSEARCH (and GEOSEARCHSTORE) as the modern replacement. Same job — nearest members in a radius — cleaner syntax and forward-compatible APIs in node-redis v4 (geoSearchWith).

If you maintain legacy code: migrating GEORADIUS → GEOSEARCH … FROMLONLAT … BYRADIUS is usually a straight swap for nearest-driver dispatch.

Online vs offline: keep the geo index honest

A Redis geo key for dispatch must mean available right now. Otherwise GEOSEARCH returns busy or offline couriers.

• Driver status = available

  Run GEOADD with the latest GPS fix.

• offline / busy / on_delivery

  Run ZREM drivers:geo <driverId> so Redis GEOSEARCH cannot return them.

• Sync on every status/location write

  Hook the driver update path so the geo index never drifts from Mongo.

Presence sync

if (status !== 'available') {
  await redis.zRem('drivers:geo', String(driverId));
  return;
}
await redis.geoAdd('drivers:geo', {
  longitude: lng,
  latitude: lat,
  member: String(driverId),
});

Treat Redis as optional: if REDIS_URL is missing, return an empty nearest list instead of crashing. Mongo remains the source of truth for the driver profile.

Node.js nearest-driver API shape

Expose Redis GEOSEARCH behind a small authenticated route so ops and demos can verify the index:

HTTP

GET /api/logistics/drivers/nearest?lng=9.70&lat=4.05&radiusKm=5&count=20

{
  "engine": "redis-geosearch",
  "radiusKm": 5,
  "count": 2,
  "drivers": [
    { "driverId": "…", "distanceKm": 0.42 },
    { "driverId": "…", "distanceKm": 1.15 }
  ]
}

When Redis is down or unset: "engine": "unavailable", drivers: []. That keeps white-label installs bootable without Redis while production can enable REDIS_URL for real nearest-driver dispatch.

FAQ — Redis GEOSEARCH for driver dispatch

Explore logistics demos on the demo hub and the logistics feature overview.