$near not working in sails.js

[Jignesh Jigs]

Hello ,

i am working on sails.js but $near operator not working ..

Can u please help me..

In model i declare like this ->latlong:{    type:'array'  }

 var coords = [25,50];

        Restaurant.find({ latlong : { $near: coords }}).limit(1).exec(function(err, res) {

          console.log("Closest to %s is %s", coords, res);

         

        });

Await for yr reply..

Regards,

JIgnesh

[John Tomaselli]

You have to use Mongodb native as waterline does not support this. I actually had an engineer at Mongodb help me with the parameters.

The data must be in the following and is case sensitve

"ziplocation" : {

        "type" : "Point",

        "coordinates" : [ 

            -73.968, 

            40.758

        ]

    }

Good luck and let me know.

John

I use geoNear in the working example

  var vlimit = 500;// max no of records to return

var pagesize = 30;
var searchObj = {};
 lng = ziplist.LONGITUDE;
 lat = ziplist.LATITUDE;

var startpos = req.param('startpos');
......
lng

Providers.native(function (err, collection) {
                    collection.geoNear(lng, lat, {
                        num:vlimit, // max no of records to return limit: does not work
                        distanceMultiplier:3959,
                        maxDistance: vmaxDistance/3959,
                        query: searchObj, // filter
                        spherical: true
                    }, function (mongoErr, docs) {

                        if (mongoErr) {
                            console.error(mongoErr);
                            return res.send('geoProximity failed with error=' + mongoErr);
                        } else {
                            var returnCt =docs.results.length;
                            var providers= [];
                           
                            _.forEach(docs.results, function (result) {
                                providers.push(_.extend(result.obj, {
                                    dis: result.dis
                                }))
                            });
                           
                            var returnArray = dentists.splice(startpos, pagesize);
                            // push the last record with stats
                            returnArray.push({ reccount: returnCt});
                            console.log('returnCt=', returnCt);
                            return res.json({ data: returnArray });
                        }
                    });

[John Tomaselli]

Also, look at https://github.com/balderdashy/sails-mongo for support

On Friday, March 21, 2014 11:33:51 AM UTC-4, Jignesh Jigs wrote:

[Vikram Mirla]

Hi Sails team,

I am a sails.js beginner. 

I have an app developed with node.js and express, where I have a model definition for 

location as :

  loc: { type:[Number], index:'2d'}

Sails.js does nto recognize it.

So instead I used.

loc: {

       type: 'array'

    },

Now, I am not sure how to query for nearest values to a location.

With mongoose, I was able to use $near. Like this:

      Comment.find( {loc:  {$near: [ parseFloat(req.query.lon), parseFloat(req.query.lat) ],$maxDistance:20  }})

What would be equivalent with Waterline?/ Sails.js?

Would appreciate hints here. I wish to continue with Sails.js, but have been facing these migration issues.

Thanks

Vikram

[Vikram Mirla]

Hello All,

To the benefit of the community, I am copying a link which helped me get 'geoNear' working

https://github.com/balderdashy/sails-mongo/issues/46

I made few mistakes - which took more time:

- I have two 2dsphere indices in my model. 

geoNear requires that there should be only one attribute in model with 2dsphere index

-  I was incorrectly passing latitude first to geoNear function:

Right way is as follows:

  User.native(function(err, collection) {
     
      collection.geoNear(lng, lat, {
        limit: 30,
        maxDistance: 1000, // in meters
        //query: {}, // allows filtering
        distanceMultiplier: 3959, // converts radians to miles (use 6371 for km)
        spherical : true
      }, function(mongoErr, docs) {
        if (mongoErr) {
          console.error(mongoErr);

          res.send('geoProximity failed with error='+mongoErr);
        } else {

          console.log('docs=',docs);
//        res.send('proximity successful, got '+docs.results.length+' results.');
          res.json(docs.results);
        }
      });
    });

Other thing I learnt which could benefit others. In config/bootstrap.js file, if you were to set multiple configurations , use async.

var async = require('async');

module.exports.bootstrap = function(cb) {

    function updateUserStatus (done) {
         User.update({}, {
               online: false
            },
            function userUpdated(err, users) {
               if (err) {
                  console.log(err);
                  return done(err);
               } else {
                  return done();
               }
               
            }
         )
    }


   function  geoStuff (done) {
        
     User.native(function (err, collection) {
            collection.ensureIndex({ location: '2dsphere' }, function () {
           return done();
         });
      });
   }

 async.parallel([ updateUserStatus, geoStuff], cb)


};

and my Model user.js has this config.

    location: {

       type: 'json', index:'2dsphere'

    },

Mongodb entry looks like this:

{

  _id: ObjectId("5458434c6fd369ca07e0917b"),

  admin: true,

  createdAt: ISODate("2014-11-04T03:09:00.980Z"),

  email: "mirl...@gmail.com",

  encryptedPassword: "$2a$10$Y4142XzCoVNhJKLqEx934eGCAauLz2RcTzJCHO64QDrvZruMjD8SS",

  location: {

    type: "Point",

    coordinates: [

      -73.968,

      40.758

    ]

  },

  name: "mirla",

  online: true,

  title: "mirla",

}

Thanks ,

Vikram