MongoDb gesospital query with golang (with mongo-go-driver)

mongodb-go-geospital.txt

=== RUN   TestGetPointsByDistance
Inserted new Point.  f0cfed41-fba5-4a2d-8179-9737b631d3c1
<nil>
[{2d91d952-2825-4a28-ae53-5a58656c4f68 {Point [12.002 12]}} {f0cfed41-fba5-4a2d-8179-9737b631d3c1 {Point [12.002 12]}}]
--- PASS: TestGetPointsByDistance (0.00s)

points.go

package dbs

import (
	"context"
	"fmt"
	"github.com/google/uuid"
	"go.mongodb.org/mongo-driver/bson"
)

// We need this type so we can store it in our mongodb db and do geospatial queries
// https://docs.mongodb.com/manual/geospatial-queries/
type Location struct {
	GeoJSONType string  `json:"type" bson:"type"`
	Coordinates []float64  `json:"coordinates" bson:"coordinates"`
}

func NewLocation(lat, long float64) Location {
	return Location{
		"Point",
		[]float64{lat, long},
	}
}

type Point struct {
	Id string `json:"id" bson:"_id"`
	Location Location `json:"location" bson:"location"`
}

func AddPoint(point Point) (string, error) {

	point.Id = uuid.New().String()

	insertResult, err := PointCollection.InsertOne(context.TODO(), point)
	if err != nil {
		fmt.Printf("Could not insert new Point. Id: %s\n", point.Id)
		return "", err
	}
	fmt.Printf("Inserted new Point. Id: %s\n", insertResult.InsertedID)
	return point.Id, nil
}


func GetPointsByDistance(location Location, distance int) ([]Point, error) {
	var results []Point

	// You have to build an index fo this stuff
	//db.Points.createIndex( { <location field> : "2dsphere" } )

	filter := bson.D{
		{"location",
			bson.D{
				{"$near", bson.D{
					{"$geometry", location},
					{"$maxDistance", distance},
				}},
			}},
	}


	cur, err := PointCollection.Find(context.TODO(), filter)

	if err != nil {
		return []Point{}, err
	}

	for cur.Next(context.TODO()) {
		var elem Point
		err := cur.Decode(&elem)
		if err != nil {
			fmt.Println("Could not decode Point")
			return []Point{}, err
		}

		results = append(results, elem)
	}

	return results, nil
}

points_test.go

package dbs

import (
	"fmt"
	a "github.com/stretchr/testify/assert"
	"testing"
)

func TestGetPointsByDistance(t *testing.T) {
	assert := a.New(t)

	var testPoint = Point{Location: NewLocation(12.002, 12)}

	_, err := AddPoint(testPoint)
	assert.NoError(err)

	points, err := GetPointsByDistance(NewLocation(12.002, 12), 50)
	assert.NoError(err)
	
	fmt.Println(err)
	fmt.Println(points)
}