Make proxy redirect to 443 instead of 8443

[LucidNeko]

configurable-http-proxy redirects to '--port' which in this case is 8443 and unresolvable outside of the cluster.

The master branch now uses version 4.1.0 of configurable-http-proxy which added '--redirect-to' to solve this problem.

[consideRatio]

I'm reading up about the command line options for CHP.

--port (defaults to 8000) Public-facing port of the proxy
--redirect-port Redirect HTTP requests on this port to the server on HTTPS
--redirect-to Redirect HTTP requests from --redirect-port to this port

I'm explaining to myself while thinking things through.

If we the CHP accepts HTTPS traffic and will make the TLS termination, traffic on the http:// port should be redirected to the https:// port. But, a redirect is simply a response to the client saying "hey visit this address", but if that address is the container local one as compared to the address to reach it from outside, which requires a passage of the k8s Service and the Pod, then it may not end up in the right spot.

Your change makes a lot of sense to me, I'm sorry you had to experience such a slow response, thank you for your contribution! ❤️ 🌻 @LucidNeko !

For reference

Service to pod port mapping

zero-to-jupyterhub-k8s/jupyterhub/templates/proxy/service.yaml

Lines 44 to 71 in 4300ff5

	ports:
	- name: http
	port: 80
	protocol: TCP
	{{- if $autoHTTPS }}
	targetPort: 80
	{{- else }}
	targetPort: 8000
	{{- end }}
	# allow proxy.service.nodePort for http
	{{- if .Values.proxy.service.nodePorts.http }}
	nodePort: {{ .Values.proxy.service.nodePorts.http }}
	{{- end }}
	{{- if $HTTPS }}
	- name: https
	port: 443
	protocol: TCP
	{{- if or $manualHTTPS $manualHTTPSwithsecret }}
	targetPort: 8443
	{{- else if $offloadHTTPS }}
	targetPort: 8000
	{{- else }}
	targetPort: 443
	{{- end }}
	{{- if .Values.proxy.service.nodePorts.https }}
	nodePort: {{ .Values.proxy.service.nodePorts.https }}
	{{- end }}
	{{- end }}

Pod to container port mapping

zero-to-jupyterhub-k8s/jupyterhub/templates/proxy/deployment.yaml

Lines 99 to 107 in 4300ff5

	ports:
	{{- if or $manualHTTPS $manualHTTPSwithsecret }}
	- containerPort: 8443
	name: proxy-https
	{{- end }}
	- containerPort: 8000
	name: proxy-public
	- containerPort: 8001
	name: api

[meeseeksmachine]

This pull request has been mentioned on Jupyter Community Forum. There might be relevant details there:

https://discourse.jupyter.org/t/manual-https-how-to-forward-from-http/2362/3