geoNear not returning any results - node.js

Question

I'm trying to use geoNear to return documents in my collection that have latitude and longitude coordinates, but not getting any results even though there are documents in the collection that have latitude and longitude coordinates. I'm using mlab to store my data, for example, here is a document in my collection.
var trucker = db.collection('trucker');
{
"_id": {
"$oid": "581e82d00f192a694bb56679"
},
"latitude": 77.0551642746301,
"longitude": 10.825842664395019,
"loc": [
77.0551642746301,
10.825842664395019
],
}
I have the coordinates in two different ways, because I was trying to see if geoNear would pick up the location, and return the result, but still can't find it. This is how I'm using geoNear currently, to find results
exports.geoNear = function (lat, lon ,res, next)
{
console.log("Inside geoNear");
var job = {};
job.lon = JSON.parse(lon);
job.lat = JSON.parse(lat);
console.log(job.lon);
console.log(job.lat);
trucker.geoNear([job.lon, job.lat], function(err, success){
if(success) {
res(success);
} else {
console.log('Response error' + err);
}
});
};
app.get('/geoFind', function(req, res) {
AM.geoNear('48.99759239999999', '-123.0683089', function(o){
res.send(200,o);
});
});
I am getting this result when visiting localhost:8000/geoFind:
{
"waitedMS": 0,
"results": [],
"stats": {
"nscanned": 0,
"objectsLoaded": 0,
"maxDistance": 0,
"time": 0
},
"ok": 1
}
Now, I have tried many different ways such as the following but get, Response errorMongoError: 'near' field must be point with the following:
trucker.createIndex( { loc : "2dsphere" } )
trucker.geoNear({loc: {type: "Point", coordinates: [job.lon,job.lat]}}, {spherical: true}, function(err, success) {
if(success){
res(success);
} else {
console.log('Response error '+err + job.lon +':' + job.lat);
}
});
Now, I'm wondering how do I use geoNear to return documents with latitude and longitude coordinates? Does latitude and longitude need to be stored in the database a specific way? I tried db.command() as well with geoNear and I always get db.command is not a function, same with trucker.command or trucker.db.db.command or trucker.db.command (anything with command to get data from the database which I think is because I'm using mongoose not mongoclient, because my database it set up with mlab). Nothing I've tried has worked which is why I'm now asking this question as I've tried just about every way imaginable to get results from my database using geoNear.

Answer 1

I got back at it this morning and did some more testing because it didn't make sense to me why I was not getting any results, so I created a brand new collection called location, and inserted 1 document to test and it worked, then 2 documents that look like the following and that worked too:
{
"_id": {
"$oid": "581cc2f430c34502e36eb148"
},
"truckerID": "b233a9eaaedc63730e71a8b542606ee82e0aa5e5",
"name": "Justin",
"email": "Justin#gmail.com",
"company": "Justins Shipping",
"user": "justin1",
"pass": "D6Mvu6rUur758f37eac7010958c14557bb4df9871a",
"phone": "1234567890",
"location": [
-73.9928,
40.7193
]
}
{
"_id": {
"$oid": "581cc2f530c34502e36eb158"
},
"truckerID": "b233a9eaaedc63731e72a8b542606ee82e0aa7a6",
"name": "Alan",
"email": "Alan#gmail.com",
"company": "Alans Shipping",
"user": "alan1",
"pass": "D6Mvu6fUur758f37eac7010958c14557bb4df9872c",
"phone": "1234567890",
"location": [
-122.4194155,
37.7749295
]
}
Apparently, location does have to be in the format,
location: [longitude, latitude]
or geoNear will not be able to find your document.
The really interesting finding to me, was that if you have a collection, with 10 documents, and there are documents in your collection that don't have:
location: [longitude, latitude]
geoNear will not get any results either. If even one document does not have that field, location: [longitude, latitude], geoNear will also not be able to find anything, or return any results after having done some more testing.
The following worked for me after creating those 2 new documents in a new collection for testing purposes using mongoose and mlab.
exports.geoNear = function (lon, lat ,res, next)
{
console.log("Inside geoNear");
var job = {};
job.lon = JSON.parse(lon);
job.lat = JSON.parse(lat);
console.log(job.lon);
console.log(job.lat);
locations.geoNear([job.lon, job.lat], {spherical: true}, function(err, success){
if(success) {
res(success);
} else {
console.log('Response error' + err);
}
});
}
var AM = require('./modules/account-manager');
app.get('/geoFind', function(req, res) {
AM.geoNear('-73.99279', '40.719296', function(o){
res.send(200,o);
});
});
and I got the following result:
{
"waitedMS": 0,
"results": [
{
"dis": 1.4957325341976439e-7,
"obj": {
"_id": "581cc2f430c34502e36eb148",
"truckerID": "b233a9eaaedc63730e71a8b542606ee82e0aa5e5",
"name": "Justin",
"email": "Justin#gmail.com",
"company": "Justins Shipping",
"user": "justin1",
"pass": "D6Mvu6rUur758f37eac7010958c14557bb4df9871a",
"phone": "1234567890",
"location": [
-73.9928,
40.7193
]
}
},
{
"dis": 0.6482546796756842,
"obj": {
"_id": "581cc2f530c34502e36eb158",
"truckerID": "b233a9eaaedc63731e72a8b542606ee82e0aa7a6",
"name": "Alan",
"email": "Alan#gmail.com",
"company": "Alans Shipping",
"user": "alan1",
"pass": "D6Mvu6fUur758f37eac7010958c14557bb4df9872c",
"phone": "1234567890",
"location": [
-122.4194155,
37.7749295
]
}
}
],
"stats": {
"nscanned": 24,
"objectsLoaded": 2,
"avgDistance": 0.3241274146244688,
"maxDistance": 0.6482546796756842,
"time": 6
},
"ok": 1
}
I hope this answer helps someone else down the line who is also wondering why geoNear isn't returning any results.
EDIT: After doing even more research, it was actually because the collection needs to have a geospatial index created from the get-go. I tried adding the location field to all documents in the collection but still could not get any results back. Once I removed my collection entirely in mlab called "trucker" and re-added it, I was finally able to search that index and get results.
This line is needed initially:
trucker.createIndex( { location : "2dsphere" } )
Then you can use geoNear to find users near your location such as the following:
trucker.geoNear([job.lon, job.lat], {maxDistance:5000, distanceMultiplier: 6378137, spherical: true}, function(err, success){
if(success) {
res(success);
} else {
console.log('Response error' + err);
}
});