How to find model dimensions through ROS?

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Hi there,

I am trying to get the model dimensions of different models loaded into the gazebo environment. Environment consist of many single linked obstacle models, mainly of 3 shapes: box, cylinder and sphere. I am able to retrieve the model pose using gazebo_msgs::GetModelState service. However, there seems to be no service or topic containing the data related to radius of cylinder or size of a box in the environment. Is there an easy way to access these parameters without having to define it other than in the world file/ model plugin?

Best regards