How to resize the first disk size when using "POST /vApp/{id}/action/recomposeVApp" to initialize a vm from a vapptemplate?

I want to add a vm to an exist vapp,and the vm will be initialized from a vapptemplate.So ,I use "POST /vApp/{id}/action/recomposeVApp".

The disk size in the vapptemplate is 10G,I want to resize to 15G,but the "POST /vApp/{id}/action/recomposeVApp" operation doesn't have

any parameter to resize the disk.

Who know how to do this?

Thanks!