src/Api/Resolver/ApiResolver.php
public function resolve(string $variable)
    {
        $matches = [];

        if (!$this->isMatch($variable, $matches)) {
            throw new UnresolvedException('Variable pattern "'.$variable.'" is not valid.');
        }

        $service = $matches[1];
        $resource = $matches[2];
        $id = $matches[3];
        $property = $matches[4];
        $model = $this->api->get($service.'.'.$resource)->get($id);
        $accessor = PropertyAccess::createPropertyAccessor();

        try {
            $value = $accessor->getValue($model, $property);
        } catch (Exception $exception) {
            throw new UnresolvedException('Variable pattern "'.$variable.'" is not valid.', 0, $exception);
        }

        return $value;
    }
public function resolve(string $variable)
    {
        $matches = [];

        if (!$this->isMatch($variable, $matches)) {
            throw new UnresolvedException('Variable pattern "'.$variable.'" is not valid.');
        }

        $service = $matches[1];
        $resource = $matches[2];
        $id = $matches[3];
        $property = $matches[4];
        $model = $this->api->get($service.'.'.$resource)->get($id);
        $accessor = PropertyAccess::createPropertyAccessor();

        try {
            $value = $accessor->getValue($model, $property);
        } catch (Exception $exception) {
            throw new UnresolvedException('Variable pattern "'.$variable.'" is not valid.', 0, $exception);
        }

        return $value;
    }
{@inheritdoc}