tryParseEventLine static method

TraceEventRecord? tryParseEventLine(String line)

Parses one trace line into TraceEventRecord when it contains a structured event emitted by event.

Returns null when the line is not an event line or is malformed.

Implementation

static TraceEventRecord? tryParseEventLine(String line) {
  final parsedLine = _parseLine(line);
  if (parsedLine == null) return null;
  final message = parsedLine.message;
  if (!message.startsWith(_eventMarker)) return null;

  final jsonPayload = message.substring(_eventMarker.length);
  final decoded = _decodeJsonObject(jsonPayload);
  if (decoded == null) return null;

  final version = decoded['v'];
  if (version is! num || version.toInt() != _eventSchemaVersion) {
    return null;
  }
  final type = decoded['type'];
  if (type is! String || type.trim().isEmpty) return null;

  final fields = <String, Object?>{};
  for (final entry in decoded.entries) {
    if (entry.key == 'v' || entry.key == 'type') continue;
    fields[entry.key] = entry.value;
  }
  return TraceEventRecord(
    timestampUs: parsedLine.timestampUs,
    tag: parsedLine.tag,
    type: type,
    fields: fields,
  );
}