Cache the counts of an associated collection.

All definitions should be made server side only.

// Sets up a 'booksCount' field on each author
Authors.maintainCountOf(Books, 'authorId');

// TODO: more examples

collection1.maintainCountOf(collection2, lookup, [name])

1. collection1

The collection to store the counter on

2. Arguments

collection2 — Meteor Collection
The collection to maintain a count of

lookup — String or Function
The field name on collection2 to perform the match against collection1 _id
or a callback function returning a value to match against collection1 _id

name — String
Optional. Specify a custom counter field name

MIT. (c) Percolate Studio

counter-cache was developed as part of the Verso project.