Gallery package root url

AU/Public/Update-Package.ps1

@@ -224,8 +224,11 @@ function Update-Package {
         $script:is_forced = $false
         if ([AUVersion] $Latest.Version -gt [AUVersion] $Latest.NuspecVersion) {
             if (!($NoCheckChocoVersion -or $Force)) {
-                if ( !$au_GalleryUrl ) { $au_GalleryUrl = 'https://chocolatey.org' } 
-                $choco_url = "$au_GalleryUrl/packages/{0}/{1}" -f $global:Latest.PackageName, $package.RemoteVersion
+                if ( !$au_GalleryPackageRootUrl ) { 
+                    if ( $au_GalleryUrl ) { $au_GalleryPackageRootUrl = "$au_GalleryUrl/packages" }
+                    else { $au_GalleryPackageRootUrl = 'https://chocolatey.org/packages' }
+                }
+                $choco_url = "$au_GalleryPackageRootUrl/{0}/{1}" -f $global:Latest.PackageName, $package.RemoteVersion
                 try {
                     request $choco_url $Timeout | out-null
                     "New version is available but it already exists in the Chocolatey community feed (disable using `$NoCheckChocoVersion`):`n  $choco_url" | result

CHANGELOG.md

@@ -1,5 +1,10 @@
 # AU Project Changelog
 
+## NEXT
+
+- Added `$au_GalleryPackageRootUrl` as a slightly more flexible alternative to `$au_GalleryUrl` ([#250](https://github.com/majkinetor/au/pull/255))
+  - `$au_GalleryUrl` is still maintained for compatibility
+
 ## 2021.7.18
 
 - Fixed bad packaging of previous version

README.md

@@ -284,7 +284,9 @@ This is the same as if you added the parameters to `update` function inside the
 
 however, its way easier to setup global variable with manual intervention on multiple packages.
 
-There is also a special variable `$au_GalleryUrl` using which you can change the URL that is used to check if package is already pushed. It defaults to https://chocolatey.org and you can change it if you need to this option for 3rd party or internal package repositories.
+There is also a special variable `$au_GalleryPackageRootUrl` that can be added to `update.ps1` to change the URL that is used to check if package is already pushed. It defaults to `https://chocolatey.org/packages` and you can change it if you need this option for 3rd party or internal package repositories.
+
+> Note: The `$au_GalleryUrl` variable also performs this function, but `$au_GalleryPackageRootUrl` allows more flexibility for 3rd party package repositories.  The `$au_GalleryUrl` will still work for compatibility, but makes assumptions about the URL that may not work in all situations.  
 
 ### Reusing the AU updater with metapackages