MongoDB/mongoose creating a relation between two models? - node.js

Question

I am looking to create a one-to-many relationship following this pattern http://docs.mongodb.org/manual/tutorial/model-referenced-one-to-many-relationships-between-documents/
I have an Exercise.js schema, which will contain a collection of exercises.
var exerciseSchema = new mongoose.Schema({
_id: String,
title: String,
description: String,
video: String,
sets: Number,
reps: String,
rest: Number
});
Then I have a workout plan BeginnerWorkout.js schema
var workoutDaySchema = new mongoose.Schema({
_id: String,
day: Number,
type: String,
exercises: Array
});
I want to associate an array of exercises to the workoutDaySchema, this contains a collection of workout days for a particular workout, each day has a collection of exercises.
I have a seeder function that generates the workout for me.
check: function() {
// builds exercises
Exercise.find({}, function(err, exercises) {
if(exercises.length === 0) {
console.log('there are no beginner exercises, seeding...');
var newExercise = new Exercise({
_id: 'dumbbell_bench_press',
title: 'Dumbbell Bench Press',
description: 'null',
video: 'null',
sets: 3, // needs to be a part of the workout day!!
reps: '12,10,8',
rest: 1
});
newExercise.save(function(err, exercises) {
console.log('successfully inserted new workout exercises: ' + exercises._id);
});
} else {
console.log('found ' + exercises.length + ' existing beginner workout exercises!');
}
});
// builds a beginner workout plan
BeginnerWorkout.find({}, function(err, days) {
if(days.length === 0) {
console.log('there are no beginner workous, seeding...');
var newDay = new BeginnerWorkout({
day: 1,
type: 'Full Body',
exercises: ['dumbbell_bench_press'] // here I want to pass a collection of exercises.
});
newDay.save(function(err, day) {
console.log('successfully inserted new workout day: ' + day._id);
});
} else {
console.log('found ' + days.length + ' existing beginner workout days!');
}
});
}
So my question is inside building a workout plan, how can I associate the exercises into the exercises key using mongoose?

Answer 1

Try this:
exercises: [{ type: mongoose.Schema.Types.ObjectId, ref: 'Exercise', required: false }]
And add an exercise to the workout using the exercise._id (In your code above you'd need to put this in the relevant callback such as the callback for .save on the exercise):
newDay.exercises.push(newExercise._id);
_id is generally a generated number so I don't know if you can set it to the text string you suggest.
When you .find() a workout you'll need to populate the exercises too. Something like:
BeginnerWorkout.find({}).
.populate('exercises')
.exec(function(err, exercises) {
//etc