Investigation of using multiple domain names for grafana, and deployer referencing one specific

[consideRatio]

The deployer script reads grafana.ingress.tls[0].hosts[0], selecting out hosts[0] specifically as a host to return for a cluster. If a redirect is setup, maybe there won't be issues, maybe there will be - I'm wasn't sure so I investigated.

Conclusion

I think we should be fine. urllib.request.urlopen follows redirects, and so does requests.get it seems. As long as GET and POST are similar, we'll be fine.

Action points

• Perhaps update docstring of get_grafana_url to mention all existing usage of the returnvalue makes it acceptable to pick one single.

Investigation

get_grafana_url hardcodes to hosts[0]

infrastructure/deployer/grafana/grafana_utils.py

Lines 12 to 30 in d4f0fdc

	def get_grafana_url(cluster_name):
	"""
	Return a Grafana instance URL using the cluster's "support.values.yaml"
	file's grafana.ingress.tls[0].hosts[0] config.
	"""
	cluster_config_dir_path = find_absolute_path_to_cluster_file(cluster_name).parent
	config_file = cluster_config_dir_path.joinpath("support.values.yaml")
	with open(config_file) as f:
	support_config = yaml.load(f)
	grafana_tls_config = (
	support_config.get("grafana", {}).get("ingress", {}).get("tls", [])
	)
	if not grafana_tls_config:
	raise ValueError(f"grafana.ingress.tls config for {cluster_name} missing!")
	# We only have one tls host right now. Modify this when things change.
	return "https://" + grafana_tls_config[0]["hosts"][0]

Reference sof get_grafana_url

Grafana API requests via deploy_grafana_dashboards

This function clones the https://github.com/jupyterhub/grafana-dashboards repo and passes the grafana URL to the ./deploy.py script in that project

infrastructure/deployer/deployer.py

Line 96 in d4f0fdc

def deploy_grafana_dashboards(

When ./deploy.py from that project is used, it sends GET and POST requests using this function. I think they may very well redirect correctly and we should be fine. But I don't know for sure. Some tools like curl require you to for example explicitly pass a flag to say that redirects should be followed.

It seems the following is used: from urllib.request import urlopen, Request and testing against https://google.com I note that it does follow the 301 redirect for a GET request at least.

Grafana API requests via new_grafana_token and update_central_grafana_datasources

infrastructure/deployer/grafana/grafana_tokens.py

Line 160 in d4f0fdc

def new_grafana_token(

infrastructure/deployer/grafana/central_grafana.py

Line 101 in d4f0fdc

def update_central_grafana_datasources(

Seems to use import requests and that seem to follow redirects at least for GET requests.

Related

• QCL hub configuration with two hosts