Add X-Forwarded-Prefix header

apache/proxy-to-virtual-path.conf

@@ -1,4 +1,5 @@
 Listen 80
+LoadModule mpm_event_module modules/mod_mpm_event.so
 LoadModule authn_core_module modules/mod_authn_core.so
 LoadModule authz_core_module modules/mod_authz_core.so
 LoadModule unixd_module modules/mod_unixd.so
@@ -22,7 +23,7 @@ Define DS_ADDRESS backendserver-address
   SetEnvIf Host "^(.*)$" THE_HOST=$1
   RequestHeader setifempty X-Forwarded-Proto http
   RequestHeader setifempty X-Forwarded-Host %{THE_HOST}e
-  RequestHeader edit X-Forwarded-Host (.*) $1${VPATH}
+  RequestHeader setifempty X-Forwarded-Prefix ${VPATH}
   ProxyAddHeaders Off
 </Location>
 

haproxy/proxy-to-virtual-path.cfg

@@ -12,6 +12,6 @@ frontend default_port_80
   default_backend default_service
 backend default_service
   acl existing-x-forwarded-host req.hdr(X-Forwarded-Host) -m found
-  http-request add-header X-Forwarded-Host %[req.hdr(Host)]/documentserver-virtual-path unless existing-x-forwarded-host
-  reqrep ^([^\ :]*)\ /documentserver-virtual-path/(.*)     \1\ /\2
+  http-request add-header X-Forwarded-Prefix /documentserver-virtual-path unless existing-x-forwarded-host
+  http-request replace-path /documentserver-virtual-path[/]?(.*) /\1
   server onlyoffice-documentserver backendserver-address:80

iis/proxy-to-virtual-path/README.md

@@ -59,3 +59,6 @@ Add IIS server variables. You will need to add `HTTP_X_FORWARDED_PROTO`,`HTTP_X_
 * In the right-side menu locate **Manage Server Variables** and click **View Server Variables**.
 * Use the **Add...** action and add the `HTTP_X_FORWARDED_PROTO`,`HTTP_X_FORWARDED_HOST`,`HTTP_THE_SCHEME` and `HTTP_THE_HOST` one after another.
 More information on adding the variables to the IIS server can be found [here](https://www.iis.net/learn/extensions/url-rewrite-module/setting-http-request-headers-and-iis-server-variables).
+
+
+For example to work correctly, you need to add a virtual path to the documentserver configuration file %ProgramW6432%\ONLYOFFICE\example\config\local.json: server.siteUrl: "/documentserver-virtual-path/"

iis/proxy-to-virtual-path/web.config

@@ -29,7 +29,8 @@
             </conditions>
             <serverVariables>              
 			  <set name="HTTP_X_FORWARDED_PROTO" value="{HTTP_THE_SCHEME}" replace="true" />
-              <set name="HTTP_X_FORWARDED_HOST" value="{HTTP_THE_HOST}/documentserver-virtual-path" replace="true" />
+                          <set name="HTTP_X_FORWARDED_HOST" value="{HTTP_THE_HOST}" replace="true" />
+	                  <set name="HTTP_X_FORWARDED_PREFIX" value="/documentserver-virtual-path" />
             </serverVariables>
             <action type="Rewrite" url="http://docservice{R:1}" />
          </rule>

nginx/proxy-to-virtual-path.conf

@@ -22,9 +22,10 @@ map $http_upgrade $proxy_connection {
 
 proxy_set_header Upgrade $http_upgrade;
 proxy_set_header Connection $proxy_connection;
-proxy_set_header X-Forwarded-Host $the_host/documentserver-virtual-path;
+proxy_set_header X-Forwarded-Host $the_host;
 proxy_set_header X-Forwarded-Proto $the_scheme;
 proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
+proxy_set_header X-Forwarded-Prefix /documentserver-virtual-path;
 
 
 server {

traefik/proxy-to-virtual-path.toml

@@ -21,7 +21,7 @@ defaultEntryPoints = ["http"]
   passHostHeader = true
 
     [frontends.docservice.headers.customrequestheaders]
-    X-Forwarded-Host = "{{TRAEFIK_HOST}}/documentserver-virtual-path"
+    X-Forwarded-Prefix = "/documentserver-virtual-path"
 
     [frontends.docservice.routes.vpath]
     rule = "PathPrefixStrip:/documentserver-virtual-path/"