metetor_demo/lib/router.js

import "/client/templates/loading.html"
import "/client/templates/user_page.html"
import "/client/templates/not_found.html"

Router.configure({
    layoutTemplate: 'mainLayout',
    loadingTemplate: 'loading',
    notFoundTemplate: 'notFound',
    waitOn: function () {
        return Meteor.subscribe("url_res")
    }
})

// Meteor.subscribe('user_res')

Router.route("/")

Router.route("/nelson", {name: 'mainItem'})

Router.route("/user/:_id", {
    name: 'userPage'
})

Router.onBeforeAction('dataNotFound',{only: 'userPage'})