Add Okta as extension

[zinuga]

Enable a user to run Envoy with Okta extension. Once this is running, user should be able to do auth flow with Okta and test by creating a new user in Okta, very easily.

[nacx]

Can you give more details about the desired experience?
Today, configuring Okta with Envoy Gateway is about setting a SecurityPolicy like this:

apiVersion: gateway.envoyproxy.io/v1alpha1
kind: SecurityPolicy
metadata:
  name: oidc-okta
spec:
  oidc:
    provider:
      issuer: "https://dev-123456.okta.com/oauth2/default"
    clientID: "my-app-client-id"
    clientSecret:
      name: "my-app-client-secret"
    redirectURL: "https://www.example.com:8443/myapp/oauth2/callback"
    logoutPath: "/myapp/logout"

It is just ~7 lines of configuration that already work with EG.

Can you clarify what the desired experience for this extension is, and how it could simplify the existing one?

[kanurag94]

For everything about oauth/ authz -- it will be cool to have some sort of local caching with the help of the extensions. Maybe we can just build an authz caching extension instead.