[SOLVED] via api to remote upload

[Lyc]

My English isn't very good, please don't mind

I want to upload ISO via PVE api.

I let client can upload ISO file to my server(203.xx.xx.xx) and I hope ISO file can via api post to PVE server.
front-end : client choose ISO and click submit button
back-end : upload to my server -> use api upload ISO to PVE server from my server.

I use this api function
POST /api2/json/nodes/{node}/storage/{storage}/upload



but I don't know tmpfilename format
please help me.
thank you very much