filter {
  # Check if message if json compliant. (There will be one blank space in front of the log)
  if [message] =~ "\A\s+\{.+\}\z" {
    # Strip the leading whitespace.
    mutate {
      strip => ["message"]
    }
    # Load the json into worker_log
    json {
      source => "message"
      target => "worker_log"
    }
    # Add a field to the top level containing the cid value from worker_log
    mutate {
      add_field => {
        "cid" => "%{[worker_log][cid]}"
      }
    # Delete the temp field so it doesn't create 4 billion fields in ES.
    remove_field => worker_log
    }
  }
}