Add slogan config (#3752)

This is a PR for #3616

Currently added a new optional config `SLOGAN`  in ini file. When this config is set title page is modified in APP_NAME [ - SLOGAN]

Example in image below

![Selezione_075.png](/attachments/7a72171e-e730-4e57-8c97-ffc94258e00f)

Add the new config value in the admin settings page (readonly)

![Screenshot 2024-05-13 at 18-04-13 My Forgejo.png](/attachments/dad00fc2-29fa-4371-a7b9-5233eadeac13)

## TODO

* [x] Add the possibility to add the `SLOGAN` config from the installation form
* [ ] Update https://forgejo.org/docs/next/admin/config-cheat-sheet

Reviewed-on: https://codeberg.org/forgejo/forgejo/pulls/3752
Reviewed-by: 0ko <0ko@noreply.codeberg.org>
Reviewed-by: Earl Warren <earl-warren@noreply.codeberg.org>
Co-authored-by: mirko <mirko.perillo@gmail.com>
Co-committed-by: mirko <mirko.perillo@gmail.com>

modules/setting/server.go

@@ -45,6 +45,14 @@ var (
 	// AppName is the Application name, used in the page title.
 	// It maps to ini:"APP_NAME"
 	AppName string
+	// AppSlogan is the Application slogan.
+	// It maps to ini:"APP_SLOGAN"
+	AppSlogan string
+	// AppDisplayNameFormat defines how the AppDisplayName should be presented
+	// It maps to ini:"APP_DISPLAY_NAME_FORMAT"
+	AppDisplayNameFormat string
+	// AppDisplayName is the display name for the application, defined following AppDisplayNameFormat
+	AppDisplayName string
 	// AppURL is the Application ROOT_URL. It always has a '/' suffix
 	// It maps to ini:"ROOT_URL"
 	AppURL string
@@ -164,10 +172,21 @@ func MakeAbsoluteAssetURL(appURL, staticURLPrefix string) string {
 	return strings.TrimSuffix(staticURLPrefix, "/")
 }
 
+func generateDisplayName() string {
+	appDisplayName := AppName
+	if AppSlogan != "" {
+		appDisplayName = strings.Replace(AppDisplayNameFormat, "{APP_NAME}", AppName, 1)
+		appDisplayName = strings.Replace(appDisplayName, "{APP_SLOGAN}", AppSlogan, 1)
+	}
+	return appDisplayName
+}
+
 func loadServerFrom(rootCfg ConfigProvider) {
 	sec := rootCfg.Section("server")
 	AppName = rootCfg.Section("").Key("APP_NAME").MustString("Forgejo: Beyond coding. We Forge.")
-
+	AppSlogan = rootCfg.Section("").Key("APP_SLOGAN").MustString("")
+	AppDisplayNameFormat = rootCfg.Section("").Key("APP_DISPLAY_NAME_FORMAT").MustString("{APP_NAME}: {APP_SLOGAN}")
+	AppDisplayName = generateDisplayName()
 	Domain = sec.Key("DOMAIN").MustString("localhost")
 	HTTPAddr = sec.Key("HTTP_ADDR").MustString("0.0.0.0")
 	HTTPPort = sec.Key("HTTP_PORT").MustString("3000")

modules/setting/server_test.go

@@ -0,0 +1,36 @@
+// Copyright 2024 The Forgejo Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package setting
+
+import (
+	"testing"
+
+	"code.gitea.io/gitea/modules/test"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestDisplayNameDefault(t *testing.T) {
+	defer test.MockVariableValue(&AppName, "Forgejo")()
+	defer test.MockVariableValue(&AppSlogan, "Beyond coding. We Forge.")()
+	defer test.MockVariableValue(&AppDisplayNameFormat, "{APP_NAME}: {APP_SLOGAN}")()
+	displayName := generateDisplayName()
+	assert.Equal(t, "Forgejo: Beyond coding. We Forge.", displayName)
+}
+
+func TestDisplayNameEmptySlogan(t *testing.T) {
+	defer test.MockVariableValue(&AppName, "Forgejo")()
+	defer test.MockVariableValue(&AppSlogan, "")()
+	defer test.MockVariableValue(&AppDisplayNameFormat, "{APP_NAME}: {APP_SLOGAN}")()
+	displayName := generateDisplayName()
+	assert.Equal(t, "Forgejo", displayName)
+}
+
+func TestDisplayNameCustomFormat(t *testing.T) {
+	defer test.MockVariableValue(&AppName, "Forgejo")()
+	defer test.MockVariableValue(&AppSlogan, "Beyond coding. We Forge.")()
+	defer test.MockVariableValue(&AppDisplayNameFormat, "{APP_NAME} - {APP_SLOGAN}")()
+	displayName := generateDisplayName()
+	assert.Equal(t, "Forgejo - Beyond coding. We Forge.", displayName)
+}

modules/templates/helper.go

@@ -79,6 +79,12 @@ func NewFuncMap() template.FuncMap {
 		"AppName": func() string {
 			return setting.AppName
 		},
+		"AppSlogan": func() string {
+			return setting.AppSlogan
+		},
+		"AppDisplayName": func() string {
+			return setting.AppDisplayName
+		},
 		"AppSubUrl": func() string {
 			return setting.AppSubURL
 		},

modules/templates/mailer.go

@@ -28,6 +28,12 @@ func mailSubjectTextFuncMap() texttmpl.FuncMap {
 		"AppName": func() string {
 			return setting.AppName
 		},
+		"AppSlogan": func() string {
+			return setting.AppSlogan
+		},
+		"AppDisplayName": func() string {
+			return setting.AppDisplayName
+		},
 		"AppDomain": func() string { // documented in mail-templates.md
 			return setting.Domain
 		},