*/ public function fields() : array; /** * Injects specific values from the provided {@see ContextInterface} into the provided carrier * via an {@see PropagationSetterInterface}. * * @see https://github.com/open-telemetry/opentelemetry-specification/blob/v1.6.1/specification/context/api-propagators.md#textmap-inject * * @param mixed $carrier */ public function inject(&$carrier, PropagationSetterInterface $setter = null, ContextInterface $context = null): void; /** * Extracts specific values from the provided carrier into the provided {@see ContextInterface} * via an {@see PropagationGetterInterface}. * * @see https://github.com/open-telemetry/opentelemetry-specification/blob/v1.6.1/specification/context/api-propagators.md#textmap-extract */ public function extract($carrier, PropagationGetterInterface $getter = null, ContextInterface $context = null): ContextInterface; }