Can't get users using restful API with node and mongodb - node.js

Question

When I set up the route for users in server.js and test with postman/localhost I get the error message, cannot GET /users. Same with any other crud operation. How can I fix this route?
server.js
var express = require("express");
var app = express();
var bodyParser = require("body-parser");
var router = express.Router();
var mongoOp = require("./models/mongo");
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({"extended" : false}));
router.get("/",function(req,res){
res.json({"error" : false,"message" : "Hello World"});
});
router.route("/users")
.get(function(req,res){
var response = {};
mongoOp.find({},function(err,data){
// Mongo command to fetch all data from collection.
if(err) {
response = {"error" : true,"message" : "Error fetching data"};
} else {
response = {"error" : false,"message" : data};
}
res.json(response);
});
});
app.use('/',router);
app.listen(3000);
console.log("Listening to PORT 3000");
mongo.js
var mongoose = require("mongoose");
mongoose.connect('mongodb://localhost:27017/meanapi');
var mongoSchema = mongoose.Schema;
var userSchema = {
"userEmail" : String,
"userPassword" : String
};
module.exports = mongoose.model('userLogin', userSchema);

Answer 1

something helpful for these cases is to set NODE_ENV=development as an environment variable and use morgan. It prints out all the requests that hit your nodejs server with status code, method, path etc.
Here's a simple way to set it up:
if ('production' != app.get('env')) {
app.use(morgan('dev'));
}
Another thing that helps in debugging is
app.on('error', function (err) {
console.error(err); // or whatever logger you want to use
});
Ass that after all the middleware and it should print out if some requests fail to get all the way to your handlers.
Hope this helps!