onRequest method

@override void onRequest(RequestOptions options, RequestInterceptorHandler handler)

Called when the request is about to be sent.

Implementation

@override
void onRequest(RequestOptions options, RequestInterceptorHandler handler) {
  assert(() {
    final context = CausalityZone.currentContext();
    final event = CausalEvent(
      parentId: context?.eventId,
      type: CausalEventType.networkEvent,
      description: 'HTTP ${options.method} ${options.uri.path}',
      metadata: {
        'method': options.method,
        'url': options.uri.toString(),
        'path': options.uri.path,
        'phase': 'request',
        'has_body': options.data != null,
        'content_type': options.contentType ?? 'unknown',
      },
    );
    TrinityEventBus.instance.emit(event);
    // Store the event ID in options.extra so we can link the response
    options.extra['_trinity_event_id'] = event.id;
    return true;
  }());
  handler.next(options);
}