iter mgo

iter.go

iter := collection.Find(nil).Sort("$natural").Tail(5 * time.Second)
for {
     for iter.Next(&result) {
         fmt.Println(result.Id)
         lastId = result.Id
     }
     if err := iter.Close(); err != nil {
         return err
     }
     if iter.Timeout() {
         continue
     }
     query := collection.Find(bson.M{"_id": bson.M{"$gt": lastId}})
     iter = query.Sort("$natural").Tail(5 * time.Second)
}