AngularJS - always have a param as a default for a Resource

Basically I got a scenario where the API i'm accessing uses a :groupId as a part of the url in many cases. Is there a easy way to avoid passing $routeParams.groupId in each function call?

var app = angular.module('plunker', []);

app.config(["$routeProvider", function($routeProvider) {
  $routeProvider.
    when("/:groupId/location", {templateUrl: "partials/location.html", controller: "LocationCtrl"});
}]);

/* Controllers */
app.controller('LocationCtrl', function($scope, $routeParams, Location) {
  Location.groupId = $routeParams.groupId; /* Is this even possible? I want to have it available to Location instead of the below*/
  Location.query();

  Location.query({groupId: $routeParams.groupId});
});

/* Services */
app.service("Location", function($resource, $routeParams) {
  return $resource("/api/:groupId/location", {}, {
    query: {method: "GET", isArray: true}
  });
});

I think you can do this:

 app.service("Location", function($resource, $routeParams) {
    return $resource("/api/:groupId/location", {groupId:12345}, {
         query: {method: "GET", isArray: true}
    });
 });

I haven't tested it, but I believe that's how the documentation reads

If it's any help, since the above answer didn't work for me, I appended .query to the end of the call.

app.service("Location", function($resource, $routeParams) {
    return $resource("/api/:groupId/location", {groupId:'@groupId'})
                                                  .query({ groupId: 12345 });
 });