Added a section which describes how to route calibre-webs log-out button to also log out of authelia when using authelia & traefik

Setup-Reverse-Proxy.md

@@ -264,6 +264,32 @@ Setting up is as easy as:
       - 'traefik.http.middlewares.authelia.forwardauth.authResponseHeaders=Remote-User, Remote-Groups, Remote-Name, Remote-Email'
       - 'traefik.http.middlewares.authelia-basic.forwardauth.address=http://authelia:9091/api/verify?auth=basic'
 
+### Authelia & Calibre-Web Logout Button 
+calibre-web's logout button by default logs you out of calibre-web, but does not log you out of authelia.
+To log out of calibre-web and authelia at once when clickling the logout button within calibre-web you need to define a small middleware in traefik and add this to the calibre router as follows:
+
+```YAML
+http:
+  routers:
+    calibre:
+      service: calibre-web-calibre@docker
+      rule: "Host(`library.domain`)"
+      tls:
+        certResolver: "yourCertResolver"
+        domains:
+          - main: "domain"
+          - sans: "library.domain"
+      middlewares:
+        - authelia
+        - calibre-logout
+        
+middlewares:
+    calibre-logout:
+      redirectRegex:
+        regex: "https://library.domain/login"
+        replacement: "https://auth.domain/logout?rd=https%3A%2F%2Flibrary.domain%2F&rm=GET"
+```
+
 ### Traefik 2.6.0 Example (Kobo Sync Fix Enabled)
  
 The following example presumes that you are using the linuxserver Calibre-Web image for your container and that you have setup traefik 2.6.0 correctly to automatically redirect http to https requests on the websecure entry point (sometimes setup as https entrypoint)