Convert Meteor mongo string _id into ObjectId

help
1

I have a problem with one of my collections. I forgot to add the date when the document was inserted but now need it.

Standard MongoDB ObjectIDs are based on the timestamp where the ObjectId has a method that lets you determine the timestamp

var id = new ObjectId();
id.getTimestamp();

unfortunately Meteor and MiniMongo don’t use ObjectIds but strings as _id. Those strings are not the hexadecimal string representation of the MongoDB ObjectId, but something else.

Does anybody know how to reverse engineer the MiniMongo string id so I can determine the timestamp when the document was inserted?

2

Unfortunately, the minimongo string is a randomized hash. There’s no embedded timestamp.

You can use the {idGeneration: "MONGO"} flag on collections to use ObjectIds instead; which works fine on everything EXCEPT the user accounts.

3

Thank you, I just found my answer in the docs as well

ObjectID values created by Meteor will not have meaningful answers to their getTimestamp method, since Meteor currently constructs them fully randomly.

4

You might be able to do some detective work by investigating the oplog and trying to determine the datestamp information from those entries.