Push_map_as_event_on_timeout with interlaced events

Hi,

I have interlaced events that stream in every minute.

For example:

event 1:
  task_id: "routerA-site1"
    metric1: val1
    metric2: val2

event 2: 
  task_id:"routerB-site1"
    metric1: val1
    metric2: val2

event3:
  task_id:"routerA-site1"
    metric3: val3
    metric4: val4

I want to be able to aggregate event1 and event3 since they both have the same task_id. I wanted to do something similar to below but it's not producing the output I need. I don't want to map out each individual field and value manually either.

aggregate {
            task_id => "%{router}-%{site}"
            timeout_task_id_field => "task_id"
            timeout_timestamp_field => "@timestamp"
            code => "
                event.to_hash.each { |k,v|
                unless map[k]
                    map[k] = v
                end
            }
            "
            #push_previous_map_as_event => true
            push_map_as_event_on_timeout => true
            timeout => 60
        }

Thank you.