Support multiple upstreams service behind the same SSO proxy

[ccojocar]

The oauth2_proxy supports multiple upstream services for which it does path based routing.

e.g. by defining the upstreams as follows:

upstreams: [
   http://kube-svc1/app1/
   http://kube-svc2/app2/
]

The proxy will route:

https://public-domain/app1 ==> http://kube-svc1/app1
https://public-domain/app2 ==> http://kube-svc2/app2

In this way, It is possible to have Single Sign-On for both app1&app2.

[jenkins-x-bot]

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/lifecycle stale

[ccojocar]

/remove-lifecycle stale

[jenkins-x-bot]

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Mark the issue as fresh with /remove-lifecycle stale.
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/lifecycle stale

[jenkins-x-bot]

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/lifecycle rotten

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/close

[ccojocar]

/remove-lifecycle rotten