Loopback Remote Method Returning an Object

I just want to expand on documentation of remote methods and hope I can save you some time.

The documentation shows how to return a string and we can easily see how it would work for any primitive data types. The handler (i.e. Person.great function) returns a string, the REST API, wraps it with a JSON object and returns { "greetings": "Greetings... John!" }.

Now let say we have a method returning the address where this person lives. The handler would return an object (e.g. a model).

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module.exports = function(Person) {
     
  Person.address = function(personId, cb) {
    // address is an object that would look like 
    // { street: '22 Main St', city: 'San Jose', zipcode: 95148 }
    var address = ...; // do something to lookup the address based on personId
    cb(null, address);
  }
   
  Person.remoteMethod('address', {
    http: { path: '/:personId/address', verb: 'get' },
    accepts: { arg: 'personId', type: 'number', required: true },
    returns: { type: 'object', root: true }
  });
};

The thing I want to point out here is the property root: true on line 13. Without it, this REST endpoint would return a JSON like this

{
  "undefined": {
    "street": "22 Main St",
    "city": "San Jose",
    "zipcode": "95148"
  }
}

I found out about this by enabling debugging by starting the app this way:

$ DEBUG=loopback:explorer:routeHelpers node .

You can see how the default API endpoints are defined. They are very useful examples to follow.