docs(TraefikForwardAuth): helmify docs (#32974)

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Signed-off-by: Alfred Göppel <43101280+alfi0812@users.noreply.github.com>
Co-authored-by: Alfred Göppel <43101280+alfi0812@users.noreply.github.com>

charts/stable/traefik-forward-auth/docs/how-to.md

@@ -5,80 +5,139 @@ description: A How To Guide for Traefik Forward Auth
 
 :::note
 
-We highly recommend to setup [authelia](/charts/premium/authelia/setup-guide) instead.
+We highly recommend to setup [authelia](/charts/premium/authelia/setup-guide)) instead.
 
 :::
 
-This app makes it possible to have a layer of security in front of your publicly exposed apps.
+This chart makes it possible to have a layer of security in front of your publicly exposed charts.
 It supports Google, OIDC, and generic OAuth2.
 Please read the [GitHub README of the original project](https://github.com/thomseddon/traefik-forward-auth) for your
 authentication options.
 
 :::note
 
-generally, phone apps do not support redirection during their authentication flow, so this middleware is more suitable for
+Generally, phone apps do not support redirection during their authentication flow, so this middleware is more suitable for
 protecting portals that you would access through a browser.
 
 :::
 
 ## A standard setup (auth host mode)
 
-This method will add a middleware to the traefik instance with Google authentication which then you can apply on any apps
+This method will add a middleware to the traefik instance with Google authentication which then you can apply on any charts
 with either subdomain or path prefix Ingress rules.
 The example domain will be `https://example.com` which should be substituted to your externally accessible domain name.
 
 ### Setting up traefik-forward-auth
+Follow this steps [here](https://github.com/thomseddon/traefik-forward-auth#google) to setup Google developer console.
+Assuming you have set up the `Client ID for Web application` in the Google developer console and set the `Authorized redirect URIs` to
+`https://auth.example.com/_oauth`, start deploying traefik-forward-auth.
 
-Assuming you have set up the `Client ID for Web application` in the developer console and set the `Authorized redirect URIs` to
-`https://auth.example.com/_oauth`, start installing traefik-forward-auth:
+Most important details to configure:
+- Setup ingress to `auth.example.com`
+- Set a `secret` (it's mandatory, but can be any string of your choosing).
+- Set `authHost` to `auth.example.com`.
+- Add your email to `whitelist` as array.
+- Add your root domain to `cookieDomain`
+- Set the `clientId` and `clientSecret` to the ones presented on the developer console. 
+- `prompt` needs to be set empty.
+- As it is a stateless program, it doesn't need any special permissions or storage.
 
-- Set a `Secret` (it's mandatory, but can be any string of your choosing).
-- Set `Auth host` to `auth.example.com`.
-- Add your email to `Whitelist`.
+```yaml
+// values.yaml
+ingress:
+  main:
+    enabled: true
+    hosts:
+      - host: auth.${DOMAIN}
+    integrations:
+      traefik:
+        enabled: true
+      certManager:
+        enabled: true
+        certificateIssuer: cloudflare
 
-![auth-options](./img/auth-options.png)
+tfaAppOptions:
+  secret: something-random
 
-- Add your root domain to `Cookie options`.
+tfaAuthOptions:
+  authHost: auth.${DOMAIN}
+  urlPath: /_oauth
+  defaultAction: auth
+  defaultProvider: google
+  whitelist:
+    - ${EMAIL1}
+    - ${EMAIL2}
+    - ${EMAIL3}
 
-![cookie-options](./img/cookie-options.png)
+tfaCookieOptions:
+  cookieDomain:
+    - ${DOMAIN}
 
-- Set the `Client ID` and `Client Secret` to the ones presented on the developer console. `Prompt` can be left empty.
-
-![google-options](./img/google-options.png)
-
-- Set up Ingress for the app as `auth.example.com` as usual.
-- That's it, since this is a stateless program, it doesn't need any special permissions or storage.
+tfaGoogleOptions:
+  clientId: ${GOOGLE_CLIENTID}
+  clientSecret: ${GOOGLE_SECRET}
+  prompt: ""
+```
+<br>
 
 ### Creating the middleware on traefik
 
-The traefik instance has to be made aware of the forward authentication. Edit your traefik installation:
+The traefik instance has to be made aware of the forward authentication. Edit in traefik configuration:
 
-- Go to `websecure` entrypoint and enable `Accept forwarded headers`.
+- Add to `websecure` entrypoint and enable `Accept forwarded headers`.
 - Add your default gateway (internal router IP) to `Trusted IPs` if using hairpin NAT. If you are using DNS override for your
-  domain name, you can probably skip this step.
+  domain name, you can probably skip this part.
 
-![traefik-forwarded-headers](./img/traefik-forwarded-headers.png)
+```yaml
+service:
+  tcp:
+    loadBalancerIP: ${IP_TRAEFIK}
+    ports:
+      websecure:
+        forwardedHeaders:
+          enabled: true
+          trustedIPs:
+            - 192.168.1.1
+```
 
-- Go to `Middlewares` and add a `forward-auth` one.
-- Name it (use a short one if planning to add to many apps).
-- Add `https://auth.example.com/_oauth` as address. This will redirect initial requests to the traefik-forward-auth container.
-- Check `trustForwardHeader`.
-- Add `X-Forwarded-User` to `authResponseHeaders`.
+- Add the correct middleware
 
-![traefik-middleware](./img/traefik-middleware.png)
+```yaml
+middlewares:
+  forwardAuth:
+    - name: auth
+      address: http://traefik-forward-auth.traefik-forward-auth:4181/_oauth
+      authResponseHeaders:
+        - X-Forwarded-User
+      trustForwardHeader: true
+```
 
-### Applying the middleware on apps
+### Applying the middleware on charts
 
-To actually use the forward authentication, you have to add it to either a chain or by itself to existing app Ingresses.
+To actually use the forward authentication, you have to add it to either a chain or by itself to existing charts Ingresses.
 
-![ingress-middleware](./img/ingress-middleware.png)
+```yaml
+ingress:
+  main:
+    enabled: true
+    hosts:
+      - host: chart.${DOMAIN} 
+    integrations:
+      traefik:
+        enabled: true
+        middlewares:
+          - name: auth
+            namespace: traefik
+```
 
-### Per-app whitelist
+### Per-chart whitelist
 
-In case you need per-app whitelists, you have two options: set up multiple instances of traefik-forward-auth (cumbersome) or
+In case you need per-chart whitelists, you have two options: set up multiple instances of traefik-forward-auth (cumbersome) or
 use custom rules. Consult the readme of the original project how to set them.
 
 ### Testing
 
 Opening your URL should result in being redirected to Google authentication. Subsequent checks if the auth is working can be
 made by opening an incognito window.
+
+![signin](./img/sign_in.png)