LogDataAggregator

The LogDataAggregator is a sequencer block, that collects value sample events from CDP Logger, aggregates them by Path and sends out compacted value series using Protocol Buffers encoding.

The block can be useful when CDPLogger data needs to be sent over a slow or expensive communication line, to speed up the communication and reduce the bandwidth usage.

Block receives ValueLogReader Data events (i.e. Path plus value sample data like Timestamp, Value and ValueType) and groups them by the Path. When some sample groups become larger than the configured maximum or the ValueType has been changed, then the previously collected value samples for the Path will be encoded and sent to the block output, together with the Path value. The following Protocol Buffers message is used to encode value sample list:

syntax = "proto3";
message AggregatedData {
  string valuetype = 1;
  repeated uint64 timestamp_deltas = 2;
  repeated double d_values = 3;
  repeated float f_values = 4;
  repeated uint64 ui64_values = 5;
  repeated sint64 i64_values = 6;
  repeated uint32 ui32_values = 7;
  repeated sint32 i32_values = 8;
  repeated uint32 us_values = 9;
  repeated sint32 s_values = 10;
  repeated uint32 uc_values = 11;
  repeated int32 c_values = 12;
  repeated bool b_values = 13;
  repeated string str_values = 14;
}

To decode these messages on the receiver end, a companion LogDataDisaggregator block can be used, that can decode these messages back to individual value samples again.

Events

Arguments

Properties