春季数据mongo地理空间查询

Question

I have been trying to use a geospatial query to fetch data into a pojo with no success.

Here is an example data in my monogdb collection

{
    "_id" : ObjectId("597b8c9a21871eeabd5a1cf5"),
    "amb_id" : 10,
    "amb_number" : "KL25 8945",
    "driver_name" : "Amal Shaji",
    "driver_licence_id" : "12/4562/2017",
    "ownership" : "Amrita Institute of Medical Science",
    "ownership_address" : "Peeliyadu Road, Ponekkara, Edappally, Ernakulam",
    "location" : {
        "type" : "Point",
        "coordinates" : [
            76.293485,
            10.032871
        ]
    }
}

The below mongo query works perfectly fine in the mongoshell

 db.trial.find( 
  { location : 
  { $near :{ 
    $geometry :{  
      type : "Point" ,  
      coordinates : [ 76.2 , 9.9 ] } ,
      $maxDistance : 20000            }
      } 

  } 
  )
  .pretty();

Here is the pojo that I have been trying to fetch the data into

@Document(collection = "trial")
    public class Ambulance {
        @Id
        String id;
        @Field("amb_id")
        String ambulanceId;
        @Field("amb_number")
        String licensePlateNumber;
        @Field("driver_name")
        String driverName;
        @Field("driver_licence_id")
        String driverLicenseNumber;
        @Field("ownership")
        String ownerShip;
        @Field("ownership_address")
        String ownerShipAddress;
        @GeoSpatialIndexed(name="Location")
        Double[] location;

        //setters and getters
   }

Here is the repository I have been using

@ComponentScan
@Repository
public interface AmbulanceRepo extends MongoRepository<Ambulance, String> {
  GeoResults<Ambulance> findByLocationNear(Point p, Distance d);
}

and the controller

@RestController
@CrossOrigin(origins = "http://localhost:4200")
@RequestMapping("/")
public class NearbyAmbulanceController {

    private AmbulanceRepo ambulanceRepo;

    @Autowired
    public NearbyAmbulanceController(AmbulanceRepo repo){
        this.ambulanceRepo = repo;
    }

    @RequestMapping(value="/nearbyAmbulance",method = RequestMethod.POST)
    @ResponseBody
    public GeoResults<Ambulance> getAmbulanceDetails(
            @RequestBody LocationRequest locationRequest){
        System.out.println("lati "+locationRequest.getLatitude()+ " long "+locationRequest.getLongitude()+" d "+locationRequest.getDistance());
//        List<Ambulance> ambulanceList=this.ambulanceRepo.findByLocationNear(new Point(Double.valueOf(locationRequest.getLongitude()),Double.valueOf(locationRequest.getLatitude())),new Distance(locationRequest.getDistance(), Metrics.KILOMETERS));
        Point point = new Point(locationRequest.getLatitude(), locationRequest.getLongitude());
        Distance distance = new Distance(locationRequest.getDistance(), Metrics.KILOMETERS);
        GeoResults<Ambulance> ambulanceList=this.ambulanceRepo.findByLocationNear(point,distance);
        System.out.println(ambulanceList);
        return ambulanceList;
    }
}

Every time I try it I get no results. I am sure that I have data in the given point and nearby locations and I was even able to use the mongoshell to fetch those. I have feeling that the problem is with the way that I have annotated the location field in the entity. Is there anything that I am missing? Any help is appreiciated.

Answer 1

Seems like there were more than one database in mongodb that had collections by the name 'trial'. I tried removing all those and now it is working fine. Spring data wasn't able to figure out which collection to be queried on as there were multiple collection with the same name in different databases. Hope this helps someone, cause I have just wasted a couple of days on this.

Answer 2

Spring MongoDb Geo spatial query: It is tested well.

   public List<MachineDetails> searchbylocation(String lat, String longt, String maxDistance) {
            BasicQuery query1 = new BasicQuery("{geoLocation:{ $near: { $geometry: { type: 'Point',coordinates: ["+ lat+","+ longt+" ] }, $minDistance: 10, $maxDistance: "+maxDistance+"}}}");

            List<MachineDetails> venues1 = mtemplate.find(query1, MachineDetails.class);

return venues1;
}