If you like the convenience of transferring a file temporarily into the cloud to download it elsewhere (great for getting stuff out of a rancher environment), check out patchbay[0]. It uses what it calls 'HTTP channels' so if you start a POST request to a patchbay URL, it will block until a corresponding GET is made to the same endpoint which will receive the data from your POST. The operation can be done in reverse as well, with the GET blocking until the POST begins.

[0] https://patchbay.pub/