docs: add argocd oidc integration (#3691)

docs/content/en/integration/openid-connect/argocd/index.md

@@ -0,0 +1,97 @@
+---
+title: "ArgoCD"
+description: "Integrating ArgoCD with the Authelia OpenID Connect Provider."
+lead: ""
+date: 2022-07-12T17:51:47+10:00
+draft: false
+images: []
+menu:
+  integration:
+    parent: "openid-connect"
+weight: 620
+toc: true
+community: true
+---
+
+## Tested Versions
+
+* [Authelia]
+  * [v4.36.2](https://github.com/authelia/authelia/releases/tag/v4.36.2)
+* [ArgoCD]
+  * v2.4.5
+
+## Before You Begin
+
+You are required to utilize a unique client id and a unique and random client secret for all [OpenID Connect] relying
+parties. You should not use the client secret in this example, you should randomly generate one yourself. You may also
+choose to utilize a different client id, it's completely up to you.
+
+This example makes the following assumptions:
+
+* __Application Root URL:__ `https://argocd.example.com`
+* __Authelia Root URL:__ `https://auth.example.com`
+* __Client ID:__ `argocd`
+* __CLI Client ID:__ `argocd-cli`
+* __Client Secret:__ `argocd_client_secret`
+
+## Configuration
+
+### Application
+
+To configure [ArgoCD] to utilize Authelia as an [OpenID Connect] Provider use the following configuration:
+
+```yaml
+name: Authelia
+issuer: https://auth.example.com
+clientID: argocd
+cliClientID: argocd-cli
+clientSecret: argocd_client_secret
+requestedScopes:
+  - openid
+  - profile
+  - email
+  - groups
+```
+
+### Authelia
+
+The following YAML configuration is an example __Authelia__
+[client configuration](../../../configuration/identity-providers/open-id-connect.md#clients) for use with [ArgoCD]
+which will operate with the above example:
+
+```yaml
+- id: argocd
+  description: ArgoCD
+  redirect_uris:
+    - https://argocd.example.com/auth/callback
+  scopes:
+    - openid
+    - groups
+    - email
+    - profile
+  secret: argocd_client_secret
+  userinfo_signing_algorithm: none
+- description: ArgoCD CLI
+  id: argocd-cli
+  public: true
+  redirect_uris:
+    - http://localhost:8085/auth/callback
+  scopes:
+    - openid
+    - groups
+    - email
+    - profile
+  userinfo_signing_algorithm: none
+```
+
+## See Also
+
+* [ArgoCD OpenID Connect Documentation](https://argo-cd.readthedocs.io/en/stable/operator-manual/user-management/#existing-oidc-provider)
+
+[Authelia]: https://www.authelia.com
+[ArgoCD]: https://argo-cd.readthedocs.io/en/stable/
+[OpenID Connect]: ../../openid-connect/introduction.md
+
+
+
+