using default_scheduler_url as a mounting point (not root `http://address/mount`) behind proxy not working

[franckOL]

I need to mount luigi behind a nginx, for example luigi at http://address/mount. For that I configure:

[core]
default_scheduler_url=http://address/mount
....

GUI is ok and works but, CLI not due to url resolution. it happens there https://github.com/spotify/luigi/blob/c13566418c92de3e4d8d33ead4e7c936511afae1/luigi/rpc.py#L54

To understand what happened:

parsed=urlparse('http://address/mount')
url='/api/add_task'
urljoin(parsed.geturl(), url)
# ==> give 'http://address/api/add_task'
# expected http://address/mount/api/add_task

What I must do for working - slash at the end of mount point, no slash for url -:

parsed=urlparse('http://address/mount/')
url='api/add_task'
urljoin(parsed.geturl(), url)
# ==> http://address/mount/api/add_task

[honnix]

I think having the slash is expected.