Geoalchemy2 Find a location within certain distance within given coordinate

I have a flask app that first fetches a location from Google Maps API and am trying to find the location that is closer to it within 1500 meters that is in the database I have.

Here is my places model.

class Places(db.Model):
    uuid = db.Column(UUID(as_uuid=True),
                     primary_key=True,
                     server_default=text("uuid_generate_v4()"))
    name = db.Column(db.String(80), nullable=False)
    # For Near Location Querying
    geometric_point = db.Column(
        Geometry(geometry_type='POINT', srid=4326), nullable=False)

I have this query to find the entry that has location nearby the submitted lng and lat within 1500meters.

def get_nearby_aqi_node(lat, lng):
    distance_in_meters = 1500

    geo_wkb = func.Geometry(func.ST_GeographyFromText(
        'POINT({} {})'.format(lng, lat)))

    point = db.session.query(Places.name,
                                Places.uuid).\
        filter(func.ST_DFullyWithin(Places.geometric_point, geo_wkb, distance_in_meters)).\
        order_by(
        Comparator.distance_centroid(Places.geometric_point, geo_wkb)).limit(1).first()

    return point

I am getting the single point that is closer to the place but it is not within the 1500 meter restriction. I get the same result with the .filter() removed.

Your points are of the geometry type with an CRS 4326, whose unit is degrees. The filer is a distance constraint of 1500 degrees (which is meaningless).

Even though you have called once func.ST_GeographyFromText(), the output is still a geometry and the cast between the two is automatic.

You can use the geography type for both points in order to use a distance in meters.