Fix --port setting (#13288)

* Fix --port setting

Unfortunately there was an error in #13195 which set the --port
option before the settings were read. This PR fixes this by
moving applying this option to after the the settings are read

However, on looking further into this code I believe that the setPort
code was slightly odd.

Firstly, it may make sense to run the install page on a different
temporary port to the full system and this should be possible with
a --install-port option.

Secondy, if the --port option is provided we should apply it to both
otherwise there will be unusual behaviour on graceful restart

Thirdly, the documentation for --port says that the setting is
temporary - it should therefore not save its result to the configuration

(This however, does mean that authorized_keys and internal links may
not be correct. - I think we need to discuss this option further.)

Fix #13277

Signed-off-by: Andrew Thornton <art27@cantab.net>

* Update cmd/web.go

* Apply suggestions from code review

Co-authored-by: techknowlogick <techknowlogick@gitea.io>

cmd/web.go

@@ -41,6 +41,11 @@ and it takes care of all the other things for you`,
 			Value: "3000",
 			Usage: "Temporary port number to prevent conflict",
 		},
+		cli.StringFlag{
+			Name:  "install-port",
+			Value: "3000",
+			Usage: "Temporary port number to run the install page on to prevent conflict",
+		},
 		cli.StringFlag{
 			Name:  "pid, P",
 			Value: setting.PIDFile,
@@ -116,16 +121,20 @@ func runWeb(ctx *cli.Context) error {
 		setting.WritePIDFile = true
 	}
 
-	// Flag for port number in case first time run conflict.
-	if ctx.IsSet("port") {
-		if err := setPort(ctx.String("port")); err != nil {
-			return err
-		}
-	}
-
 	// Perform pre-initialization
 	needsInstall := routers.PreInstallInit(graceful.GetManager().HammerContext())
 	if needsInstall {
+		// Flag for port number in case first time run conflict
+		if ctx.IsSet("port") {
+			if err := setPort(ctx.String("port")); err != nil {
+				return err
+			}
+		}
+		if ctx.IsSet("install-port") {
+			if err := setPort(ctx.String("install-port")); err != nil {
+				return err
+			}
+		}
 		m := routes.NewMacaron()
 		routes.RegisterInstallRoute(m)
 		err := listen(m, false)
@@ -152,6 +161,12 @@ func runWeb(ctx *cli.Context) error {
 	// Perform global initialization
 	routers.GlobalInit(graceful.GetManager().HammerContext())
 
+	// Override the provided port number within the configuration
+	if ctx.IsSet("port") {
+		if err := setPort(ctx.String("port")); err != nil {
+			return err
+		}
+	}
 	// Set up Macaron
 	m := routes.NewMacaron()
 	routes.RegisterRoutes(m)
@@ -190,7 +205,6 @@ func setPort(port string) error {
 		defaultLocalURL += ":" + setting.HTTPPort + "/"
 
 		cfg.Section("server").Key("LOCAL_ROOT_URL").SetValue(defaultLocalURL)
-
 		if err := cfg.SaveTo(setting.CustomConf); err != nil {
 			return fmt.Errorf("Error saving generated JWT Secret to custom config: %v", err)
 		}

docs/content/doc/usage/command-line.en-us.md

@@ -40,6 +40,7 @@ Starts the server:
 
 - Options:
     - `--port number`, `-p number`: Port number. Optional. (default: 3000). Overrides configuration file.
+    - `--install-port number`: Port number to run the install page on. Optional. (default: 3000). Overrides configuration file.
     - `--pid path`, `-P path`: Pidfile path. Optional.
 - Examples:
     - `gitea web`