Cloudron v6.2.4 - Nginx Access-Control-Allow-Origin Policy blocks Grafana to access Prometheus

[girish]

@brutalbirdie CORS headers are set by the app, it shouldn't be platform related. So, if Grafana cannot access prometheus, it's because prometheus needs some CORS setting.

[girish]

It seems one can set --web.cors.origin as per https://manpages.debian.org/unstable/prometheus/prometheus.1.en.html . I guess we have to fix the Cloudron package to have CLI args.

[BrutalBirdie]

@girish
My problem with that is, both Grafana and Prometheus did not get updated for 2 weeks on the v6.2.4 instance.
Grafana 7.4.3 and Prometheus Server 2.25.0
They did not change but the version of Cloudron got upgraded from v6.1.2 => v6.2.4 that's the only thing that changed.

[girish]

@brutalbirdie Nothing has changed in the reverse proxy configs other than referrer-policy. So, I am surprised that it worked before. I can only think of some app update causing a problem.

[BrutalBirdie]

@girish Yes I'm also very confused about this issue.
And also that no one else reported this so far.

Did you test said issue and could replicate it @girish?

[girish]

@brutalbirdie I haven't tried this yet. Do you know if this setup requires basic auth to work in the apps?

[BrutalBirdie]

@girish Good question.
Since prometheus does use proxyAuth and grafana tries to auth via basic auth.
Could this be a problem? I think I've read something on the forum about a problem with proxyAuth?

[girish]

@brutalbirdie yes, that is most likely the issue. Let me try to push a fix.

[girish]

@brutalbirdie I have enabled it in package v1.4.1 . Can you please try?

[BrutalBirdie]

@girish On it.

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Neat! This fixed it. Big thanks for the uddate.