How do I access a MongoDB object id during creation?
You can use mongoose's .save for the purpose. Insert the object in the first model, save it, and upon receiving a success callback, use its _id for the second model,
let model = new myModel(myObject);model.save(function(err, savedObject) { let accessId = savedObject._id; refModel.create({refId: accessId}); //or something similar})The same can be done without using mongoose
db.myCollection.insert(objectToBeSaved, function(err, savedObject) { let accessId = savedObject._id; db.refCollection.insert({refId: accessId}); //or something similar })