add new docs version 7.10.x

docs/versioned_docs/version-7.10.x/configuration/providers/index.md

@@ -0,0 +1,43 @@
+---
+id: index
+title: OAuth Provider Configuration
+---
+
+You will need to register an OAuth application with a Provider (Google, GitHub or another provider), and configure it 
+with Redirect URI(s) for the domain you intend to run `oauth2-proxy` on.
+
+Valid providers are :
+
+- [ADFS](adfs.md)
+- [Bitbucket](bitbucket.md)
+- [DigitalOcean](digitalocean.md)
+- [Facebook](facebook.md)
+- [Gitea](gitea.md)
+- [GitHub](github.md)
+- [GitLab](gitlab.md)
+- [Google](google.md) _default_
+- [Keycloak](keycloak.md) (Deprecated)
+- [Keycloak OIDC](keycloak_oidc.md)
+- [LinkedIn](linkedin.md)
+- [login.gov](login_gov.md)
+- [Microsoft Azure](ms_azure_ad.md) (Deprecated)
+- [Microsoft Entra ID](ms_entra_id.md)
+- [Nextcloud](nextcloud.md)
+- [OpenID Connect](openid_connect.md)
+
+The provider can be selected using the `provider` configuration value, or set in the [`providers` array using AlphaConfig](https://oauth2-proxy.github.io/oauth2-proxy/configuration/alpha-config#providers). However, [**the feature to implement multiple providers is not complete**](https://github.com/oauth2-proxy/oauth2-proxy/issues/926).
+
+Please note that not all providers support all claims. The `preferred_username` claim is currently only supported by the 
+OpenID Connect provider.
+
+## Email Authentication
+
+To authorize a specific email-domain use `--email-domain=yourcompany.com`. To authorize individual email addresses use 
+`--authenticated-emails-file=/path/to/file` with one email per line. To authorize all email addresses use `--email-domain=*`.
+
+## Adding a new Provider
+
+Follow the examples in the [`providers` package](https://github.com/oauth2-proxy/oauth2-proxy/blob/master/providers/) to define a new
+`Provider` instance. Add a new `case` to
+[`providers.New()`](https://github.com/oauth2-proxy/oauth2-proxy/blob/master/providers/providers.go) to allow `oauth2-proxy` to use the
+new `Provider`.