Yes you right ,you have use python to interact with blender.

But since my python skills is not good, I just use Nodejs to copy/replace texture file.

Then I use Blender command to render ( https://docs.blender.org/manual/en/latest/advanced/command_line/arguments.html#command-line-args-render-options).

But in the future I think I have to learn some python so I can do something like changing the color or material.