router.js

// Option A
Router.map(function() {
  this.route('dashboards', function() {
    this.route('new');

    this.route('edit', {
      path: ':dashboard_id/edit'
    });

    this.route('show', {
      path: ':dashboard_id'
    }, function(){
      this.route('charts', function(){
        this.route('new');
    
        this.route('edit', {
          path: ':chart_id/edit'
        });
        
        this.route('show', {
          path: ':chart_id'
        })
      });
    });
  });
});

export default Router;

// Option B
Router.map(function() {
  this.resource('dashboards', function() {
    this.route('new');

    this.route('edit', {
      path: ':dashboard_id/edit'
    });

    this.route('show', {
      path: ':dashboard_id'
    }, function(){
      this.resource('charts', function(){
        this.route('new');
    
        this.route('edit', {
          path: ':chart_id/edit'
        });
        
        this.route('show', {
          path: ':chart_id'
        })
      });
    });
  });
});

export default Router;