Cannot read 'create' property of undefined - node.js

Question

I am following a tutorial on building an app with Express, Nodejs, Sequelize,Postgres.
After creating my controller and routes, the GET route works perfectly but POST route (mean to call a callback function for creating an object) fails with:
TypeError: cannot read property 'create' of undefined.
This is the controller:
let Todo = require('../models').todo;
module.exports = {
create(req, res){
return Todo
.create({title:req.body.title,})
.then(todo => res.status(201).send(todo))
.catch(error => res.status(400).send(error));
},
list(req, res){
return Todo
.all()
.then(todos => res.status(200).send(todos))
.catch(error => res.status(400).send(error));
},
};
And this is the route definition
const todosController = require('../controllers').todos;
module.exports = app => {
app.get('/api', (req, res) =>res.status(200).send({message:"welcome to the todos API!"}));
app.post('/api/todos', todosController.create);
app.get('/api/todos', todosController.list);
};
...and here is the todo model. Thanks #Yuri Tarabanko
'use strict';
module.exports = (sequelize, DataTypes) =>{
const Todo = sequelize.define('Todo', {
title:{
type:DataTypes.STRING,
allowNull: false
},
},
{
classMethods: {
associate: (models) => {
Todo.hasMany(models.TodoItem,
{
foreignKey:'todoId',
as: 'todoItems',
});
},
},
}
);
return Todo;
};
My controllers/index.js file is shown below.
const todos = require('./todos');
module.exports = {
todos,
};

Answer 1

It is because you are importing wrong...
Change:
const todosController = require('../controllers').todos;
to
const todosController = require('../controllers/todos')

Answer 2

Should be not
const todosController = require('../controllers').todos;
but
const todosController = require('../controllers');
because your create and list functions are not in todo but in root of module.exports.
create and list functions are actually in the "todo.js" file in the
"controllers" directory.
Then you should require them as
const todosController = require('../controllers/todo');
unless you have controllers/index.js which has
modules.exports={todo:require(todo)};
Also note that your file seems to be called todo, not todos.