How can I add a two column unique id to the mongodb in a meteor app?

Question

I am trying to create a two column unique index on the underlying mongodb in a meteor app and having trouble. I can\'t find anything in the meteor docs. I have tried from

Answer 1

Collection._ensureIndex(index, options)

Searching inside Meteor source code, I found a bind to ensureIndex called _ensureIndex. For single-key basic indexes you can follow the example of packages/accounts-base/accounts_server.js that forces unique usernames on Meteor:

Meteor.users._ensureIndex('username', {unique: 1, sparse: 1});

For multi-key "compound" indexes:

Collection._ensureIndex({first_id:1, another_id:1}, {unique: 1});

The previous code, when placed on the server side, ensures that indexes are set.

Warning

Notice _ensureIndex implementation warning:

We'll actually design an index API later. For now, we just pass through to Mongo's, but make it synchronous.