Node-orm saving nested objects - node.js

Question

My model is essentially
Idea has many Position
Idea has one User
Position has one Direction
Position has one Security
Position has one Idea (inverse of Idea has many Position)
I have added 'Q' promises to many of the node-orm functions to program in that manner. So find is now qFind etc...
I am struggling to find the best way to persist this to the DB (MySql):
User.qGet(1004).then(function(user) {
var newIdea = new Idea({
'openedOn': new Date()
})
newIdea.setUser(user, console.log)
Idea.qCreate(newIdea).then(function(idea) {
_.each(positions, function(position) {
Security.qFind({ticker: position.ticker}).then(function(securities){
var security = securities[0]
Direction.qFind({direction: position.direction}).then(function(directions){
var direction = directions[0]
var newPosition = Position({
'weight': 1
})
newPosition.setIdea(idea, console.log)
newPosition.setDirection(direction, console.log)
newPosition.setSecurity(security, console.log)
console.log(JSON.stringify(newPosition))
}) // Direction.qFind
}) // Security.qFind
}) // _.each
console.log(JSON.stringify(idea))
res.send(idea)
}) // Idea.qCreate
}) // User.find
Here are my problems
It is not working. When I set the idea, i get the error:
[Error: ER_BAD_NULL_ERROR: Column 'directionId' cannot be null]
The issue is I need to set three foreign keys in this object...
2. Is this the right approach to saving nested objects?

Answer 1

One solution is setting the id
var newPosition = Position({
'weight': 1
,'ideaId': idea.id
,'directionId': direction.id
,'securityId': security.id
})
Position.create(newPosition, function(e, i){
})
The problem is that /Associations/One.js calls save when setting an association.

Answer 2

I have decided to embrace the use of promises, and the Q library
Step 1 adding q nbind to interesting methods in my orm model. for instance:
model = db.models.direction
model['qFind'] = Q.nbind(model['find'], model);
Step 2 was adding instance methods to my Models to:
setDirectionByName: function(direction) {
var _this = this;
var internalSuccess = function(directions) {
_this.direction = directions[0]
_this.directionId = directions[0].id
return directions
}
return {
then: function(externalSuccess, externalFail) {
var success = _.compose(externalSuccess, internalSuccess)
Direction.qFind({direction: direction}).then(success, externalFail)
}
}
}
in this step i define an internal success method which stores the properties, and return a promise which utilizes composition to form an overall success function (the one from my model inside of the one passed to the 'then' invocation.
Step 3: handling the request and saving the data
User.qGet(1004).then(function(user) {
var newIdea = new Idea({
'openedOn': new Date()
})
newIdea.setUser(user, function(){})
Idea.qCreate(newIdea).then(function(idea) {
var positionPromises = _.map(positions, function(position) {
var newPosition = Position({
'weight': 1
,'ideaId': idea.id
})
Here I set the foreign keys, and wait for them to complete, before the Position.create is asynchronously kicked off, with a promise being returned.
return Q.all([
newPosition.setDirectionByName(position.direction)
, newPosition.setSecurityByTicker(position.ticker)
]).then(function(noop) {
//newPosition.setIdea(idea)
return Position.qCreate(newPosition)
})
}) // _.map
SO then with an array of promises for Position objects. Here I am going to wait for them all to fill, prior to returning the results tot he client
Q.all(positionPromises).then(function(positions){
console.log('RESULTS of POSITION Promises')
//console.log(JSON.stringify(positions))
//This doesn't seem to work as expected
//idea.setPositions(positions, function(e, o){ })
// kludge it
idea.positions = positions
console.log(JSON.stringify(idea))
console.log('/RESULTS of POSITION Promises')
res.send(idea)
})
console.log('FALL THROUGH')
}) // Idea.qCreate
}) // User.find