Question

I need to remove sub-docs from collection

tasks = item.tasks; // item is mongodb collection element, tasks is array of sub docs

tasks.forEach(function(task){
if (!task.finished)
     tasks.remove(task)
})

item.save()

after that I get situation when not all sub-docs with finished==true are removed.

Is there the other more correct way to do what I need?

Answer 1

You can do this atomically using an update with the $pull operator:

Items.update({_id: item._id}, {$pull: {tasks: {finished: true}}}, ...);

Seems you could also do this with MongooseArray#pull but the docs on that are so thin I’ve never figured out how to use it.