handleFrame method

void handleFrame(InspectorPeer peer, Map<String, Object?> frame)

Dispatches one decoded frame from peer. Anything that is not a well-formed request is ignored, which is what makes a liveness knock — connect, say nothing, close — cost a read loop and nothing else.

Implementation

void handleFrame(InspectorPeer peer, Map<String, Object?> frame) {
  if (frame[frameType] != typeRequest) return;
  var channel = frame[frameChannel];
  var method = frame[frameMethod];
  var id = frame[frameRequestId];
  if (channel is! String || method is! String || id is! int) return;
  if (channel == metaChannel && method == metaAttach) {
    attach(peer, id);
    return;
  }
  if (channel == metaChannel && method == metaDetail) {
    var params = frame[framePayload];
    var eventId = params is Map ? params['event'] : null;
    var encoded = eventId is int ? _details[eventId] : null;
    send(peer, {
      frameChannel: metaChannel,
      frameType: typeResponse,
      frameRequestId: id,
      framePayload: encoded == null
          // Honest about the difference between "never captured" and
          // "captured and evicted": the attacher words them differently.
          ? {'evicted': true}
          : {'details': jsonDecode(encoded)},
    });
    return;
  }
  var handler = _handlers[channel]?[method];
  if (handler == null) {
    send(peer, {
      frameChannel: channel,
      frameType: typeError,
      frameRequestId: id,
      framePayload: {'message': 'no handler for $channel.$method'},
    });
    return;
  }
  var params = frame[framePayload];
  unawaited(
    _respond(
      peer,
      channel,
      id,
      handler,
      params is Map ? params.cast<String, Object?>() : const {},
    ),
  );
}