server.js

var express = require('express'),
    session = require('express-session'),
    mongoose = require('mongoose'),
    bodyParser = require('body-parser'),
    logger = require('morgan'),
    fs = require('fs'),
    bcrypt = require('bcrypt'),
    request = require('request'),
    Todo = require('./models/todo.js'),
    app = express();

app.use(logger('dev'));
app.use(express.static('./public'));
app.use(bodyParser.urlencoded({
    extended: false
}));
app.use(bodyParser.json());
app.use(session({
    secret: "string",
    saveUninitialized: false,
    resave: false
}));

var port = process.env.PORT || 3000

app.listen(port, function() {
    console.log('server running on localhost 3000');
});

mongoose.connect('mongodb://localhost/meanAppDB', function(err) {
    if (err) {
        console.log('connection error', err);
    } else {
        console.log('connection successful');
    }
});


app.get('/', function(req, res) {
    res.send('connected via server.js route');
});

app.get('/todos', function(req, res) {
    //getting the todos from the db and sending a response back with all the data
    Todo.find().exec(function(err, todos) {
        res.send(todos);
    });
});

app.post('/todos', function(req, res) {
    //creating a new todo in the database with the data thet i got from the controller
    var todo = new Todo(req.body);
    console.log(req.body)
    todo.save(function(err) {
        if (err) {
            console.log(err);
        } else {
            //sending a response back to the controller with the todo that I created
            res.send(todo);
        }
    });
})

app.delete('/todos/:id', function(req, res) {
    Todo.remove({
        //checking if the id of the route is the same of the id of the todo
        _id: req.params.id
    }, function(err, todo) {
        if (err) {
            res.send(err)
        } else {
            //send the todo back to the controller
            res.send(todo)
        }
    });
});

app.put('/todos/:id', function(req, res) {
    console.log("here")
    console.log(req.body)
   Todo.findOneAndUpdate({
     _id: req.params.id
   }, {
    text: req.body.text
 }, function(err, todo) {
     res.send(todo);
   });
 })