Mongoose: schema.pre('save') not triggered by MyModel.update()

[Hamms]

example.js:

var mongoose = require('mongoose')
  , Schema = mongoose.Schema

mongoose.connect('mongodb://localhost/test')

var Thing = new Schema({
  title : String,
  content : String
})

Thing.pre('save', function(next){
  console.log("saving: %s (%s)", this.title, this.content)
  next()
})

var MyThing = mongoose.model('Thing', Thing)

var example = new MyThing({
  title : 'foo',
  content : 'bar'
})

example.save(function(err){
  MyThing.update({title:'foo'},{content:'baz'}, function(err, rs){
    console.log(rs)
  })  
})

Output:

$ node example.js 
saving: foo (bar)
1

The pre is triggered by the initial save, but not the update.

[aheckmann]

This is not a bug. pre save is a hook that fires on instances when their save method is called, not on the model when update is called.

Model.update let's you send atomic $set operations directly to mongodb.

[martindale]

This is a feature I'd like to have; especially helpful when upserting sparse data.

[niftylettuce]

@aheckman I agree with @martindale, I feel that in UI's where we have $.ajax form updates such as by passing a req.body._id to a post route, some type of pre method would be handy. An example use case is when you submit two numbers, and you'd like the model to have a pre('save') for calculating the total.

[niftylettuce]

perhaps pre('update') ofc

[trentmillar]

I have noticed this as well so I assume this is not considered an enhancement worth adding.

I decided to use aheckmann's approach where I need to update my object's updatedOn date field. However, where auditing is something I'd like to use at the middleware level, this approach smells.

Setting a date in my case is very sensitive to the instant the save commits to mongodb since I have a background process loading updated docs based on a moving date & time window. I'm not saying there would be a lot of time drift but aheckmann's approach vs. pre('update') would likely contain more drift by the time the save happens.

I would love to see some middleware option here.

[willynilly]

So what is the workaround? I expected pre('save') would have caught updates, which semantically seem like saves to me. Since updates are so common, it makes the save hook much less valuable.

[sohailalam2]

I am not sure if anyone is still watching this or not, but looking into the Mongoose documentations -
Mongoose
under _Notes on findAndUpdate()_ section makes a reference to issues/964 which explains why this does not work. Hope that helps! :)

[r3wt]

This is fucking bullshit. we can't do anything async in setters. idiots.

[trentmillar]

this is a really old thread but ok. There are pre's that actually inturup this or it has been figured out since the post.

[r3wt]

It's all good trent, i went ahead and reorganized my code to make a findById and then a subsequent save, so the pre save hook to salt a password still works. I guess it is what it is, though it would be nice to have a pre update hook as well, it still will take two queries to service the operation since you must read data and check if it has changed any way with isModifed

[martindale]

Tagging #964 and bumping for interest.