Make the external url of cache server configurable if necessary

cmd/input.go

@@ -46,6 +46,7 @@ type Input struct {
 	artifactServerPort                 string
 	noCacheServer                      bool
 	cacheServerPath                    string
+	cacheServerAdvertiseURL            string
 	cacheServerAddr                    string
 	cacheServerPort                    uint16
 	jsonLogger                         bool

cmd/root.go

@@ -94,6 +94,7 @@ func Execute(ctx context.Context, version string) {
 	rootCmd.PersistentFlags().BoolVarP(&input.noSkipCheckout, "no-skip-checkout", "", false, "Do not skip actions/checkout")
 	rootCmd.PersistentFlags().BoolVarP(&input.noCacheServer, "no-cache-server", "", false, "Disable cache server")
 	rootCmd.PersistentFlags().StringVarP(&input.cacheServerPath, "cache-server-path", "", filepath.Join(CacheHomeDir, "actcache"), "Defines the path where the cache server stores caches.")
+	rootCmd.PersistentFlags().StringVarP(&input.cacheServerAdvertiseURL, "cache-server-advertise-url", "", "", "Defines the URL for advertising the cache server behind a proxy. e.g.: https://act-cache-server.example.com")
 	rootCmd.PersistentFlags().StringVarP(&input.cacheServerAddr, "cache-server-addr", "", common.GetOutboundIP().String(), "Defines the address to which the cache server binds.")
 	rootCmd.PersistentFlags().Uint16VarP(&input.cacheServerPort, "cache-server-port", "", 0, "Defines the port where the artifact server listens. 0 means a randomly available port.")
 	rootCmd.PersistentFlags().StringVarP(&input.actionCachePath, "action-cache-path", "", filepath.Join(CacheHomeDir, "act"), "Defines the path where the actions get cached and host workspaces created.")
@@ -598,7 +599,7 @@ func newRunCommand(ctx context.Context, input *Input) func(*cobra.Command, []str
 		var cacheHandler *artifactcache.Handler
 		if !input.noCacheServer && envs[cacheURLKey] == "" {
 			var err error
-			cacheHandler, err = artifactcache.StartHandler(input.cacheServerPath, input.cacheServerAddr, input.cacheServerPort, common.Logger(ctx))
+			cacheHandler, err = artifactcache.StartHandler(input.cacheServerPath, input.cacheServerAdvertiseURL, input.cacheServerAddr, input.cacheServerPort, common.Logger(ctx))
 			if err != nil {
 				return err
 			}