1. If we wanted to update, say, the first todo list, conventionally, PUT requires us to send the whole updated todo resource. Now let's create a PUT route:

{
  method: 'PUT',
  path: '/todo/{id}',
  handler: (request, reply) => {
    const index = request.params.id - 1;
    // replace the whole resource with the new one
    todoList[index] = request.payload;
    return reply({ message: 'updated' });
  }
}

2. Now go to Insomnia and make the request. Remember to change the request type to PUT:

3. You should see the following response:

{
  "message": "updated"
}

4. And when you do a GET on http://localhost:8000/todo/1, you should get the updated resource: