How to correctly find objects by proximity using sequelize.js and PostGIS?

Question

I'm trying to perform a simple ST_Dwithin search using sequelize.js and PostGIS. In my database I have 3 tables of interest: Users, Neighborhoods and Addresses. All geo data is stored inside addresses table, which has references to users and neighborhoods.

return Neighborhood.findById(id).then(neighborhood => {
  return neighborhood.getAddress().then(address => {
    return Address.findAll({
      where: sequelize.where(
        sequelize.fn(
          'ST_DWithin',
          sequelize.fn(
            'ST_Transform',
            address.position,
            26986),
          sequelize.fn('ST_Transform',
            sequelize.col('position'),
            26986),
          distance),
        true
      )
    })
  })
}).catch(err => new Error(err));

First I get the address of a neighborhood and then use sequelize.fn to query with PostGIS ST_DWithin function. However this throws an error TypeError: val.replace is not a function . I believe it is something with line address.position . The column position in the table Addresses stores geometry points with type GEOMETRY and srid 4326.

The function works correctly if instead of address.position I hard code something like sequelize.fn('ST_GeomFromText', 'POINT(39.807222 -76.984722)', 4326)

Answer 1

In my case, the geometry(point) attribute is in the User entity. This is what I got working:

var lat = parseFloat(json.lat);
var lng = parseFloat(json.lng);
var attributes = Object.keys(User.attributes);
var distanceAttribute = 
  sequelize.fn('ST_Distance_Sphere', 
                sequelize.literal('geolocation'), 
                sequelize.literal('ST_MakePoint('+lat+','+lng+')'));
var distanceAlias = [distanceAttribute, 'distance'];
attributes.push(distanceAlias);

var query = {
  attributes: attributes,
  where: sequelize.where(distanceAttribute, {$lte: 100000}),
  logging: console.log
}

User.findAll(query)
  .then(function(instance){
    console.log(instance);
  });

Which produces a SQL like this:

SELECT "user_id", "user_name" ... ST_Distance_Sphere(geolocation, 
ST_MakePoint(-22.4149023,-47.56513940000002)) AS "distance" 
FROM "user" AS "User" 
WHERE ST_Distance_Sphere(geolocation, 
ST_MakePoint(-22.4149023,-47.56513940000002)) <= 100000;

I think this should work for you too by changing User to Address