tlbmc/edge_filtering.proto

edition = "2023";

package milotic_hft;

// EdgeFilter describes a per-identifier edge-side operation that
// the HFT server applies to that identifier's sample stream.
// If the server does not recognize the configured
// variant, it falls through to unfiltered streaming.
message EdgeFilter {
  oneof filter {
    OnChangeFilter on_change = 1;
    // Reserved for future filter variants.
  }
}

// OnChangeFilter emits a sample only when its value differs from the most
// recently emitted sample beyond a threshold, with an optional heartbeat
// to assert liveness when the value is steady.
message OnChangeFilter {
  // Absolute delta threshold: a sample passes the filter when
  // |current - last_emitted| > float_epsilon. 0 means emit on any change.
  // For uint64 `count` readings the threshold is float_epsilon rounded to the
  // nearest whole count.
  float float_epsilon = 1;

  // Maximum interval between emissions for this identifier when the
  // value is unchanged. 0 disables the heartbeat. Effective resolution
  // is rounded up to a multiple of export_interval_ms.
  //
  // The same cadence also re-asserts an unchanged non-OK status
  // (STALE/MISSING): with a heartbeat configured, a persistent stall
  // marker is re-emitted once per heartbeat interval instead of only
  // once on the status transition.
  int32 heartbeat_interval_ms = 2;
}