Question

I’m doing the following using Mongoose:

that.model.update({_id: dao._id}, dao,  { upsert: true }, cb);

Where dao is a mongoose representation containing (among other things) a couple of embedded documents. As a test I’ve deleted a couple of the embedded docs from the array before calling the update-method above.

The result is that the change to the array of embedded docs IS NOT persisted.

Anything I’m overlooking?

Answer 1

I solved the problem by doing something similar as proposed in the following issue: https://github.com/LearnBoost/mongoose/issues/571

For completeness some background which led to the problem.

I’m using DDD repositories which are populated on app-start. Under the hood this fetches Mongoose-objects (which are treate as DAOs in my situation) and are translated to domainobjects, which are cached in the repository. I need this separation between domainobjects and mongoose-objects, don’t ask.

This means that getById, getAll and all other public interfaces of the repo work with domainobjects and not with mongoose-objects.

When doing things like add or update on the repo this internally only updates the in-mem cache (which, again, only uses domainobjects instead of mongoose-objects)

Only when doing commit on the repo does the possibly changed collection of domainobjects get persisted. This is done by creating NEW Mongoose-objects instead of fetching Existing mongoose-objects and updating those.

This is why I can’t use dao.save() since, when I’m saving a different (just created) mongoose-object while a mongoose-object with the same id may possibly already exist in Mongo, it throws a duplicate id error.

Some relevant snippet from by code illustrating the solution:

var dao = that.createDAO(domainobject);

      //https://github.com/LearnBoost/mongoose/issues/571
      // Convert the Model instance to a simple object using Model's 'toObject' function
      // to prevent weirdness like infinite looping...
      var upsertData = dao.toObject();

      // Delete the _id property, otherwise Mongo will return a "Mod on _id not allowed" error
      delete upsertData._id;

      that.model.update({_id: dao._id}, upsertData,  { upsert: true }, cb);