ErrorBoard使用RethinkDB查询聚合

query.js

r.db('ErrorTracker').table('logs').group('message').map(function(doc){
  return {
    count: 1,
    from: doc('timestamp'),
    to: doc('timestamp'),
    browsers: r([doc('ua')('family')])
  }
}).reduce(function(left, right){
  return {
    count: left('count').add(right('count')),
    from: r.branch(left('from').lt(right('from')), left('from'), right('from')),
    to: r.branch(left('to').gt(right('to')), left('to'), right('to')),
    browsers: left('browsers').setUnion(right('browsers'))
  }
})