Show locale in url in multilingual contexts

classes/core/Core.php

@@ -25,6 +25,7 @@
 use PKP\cache\CacheManager;
 use PKP\cache\FileCache;
 use PKP\config\Config;
+use PKP\facades\Locale;
 use SplFileInfo;
 
 define('PKP_LIB_PATH', 'lib/pkp');
@@ -153,14 +154,26 @@ public static function getContextPath(string $urlInfo): string
     }
 
     /**
-     * Get the page present into the passed url information. It expects that urls were built using the system.
+     * Get localization path present into the passed
+     * url information.
+     */
+    public static function getLocalization(string $urlInfo): string
+    {
+        $locale = self::_getUrlComponents($urlInfo, 0);
+        return Locale::isLocaleValid($locale) ? $locale : "";
+    }
+
+    /**
+     * Get the page present into
+     * the passed url information. It expects that urls
+     * were built using the system.
      *
      * @param $urlInfo Full url or just path info.
      * @param $userVars (optional) Pass GET variables if needed (for testing only).
      */
     public static function getPage(string $urlInfo, array $userVars = []): string
     {
-        $page = static::_getUrlComponents($urlInfo, 0, 'page', $userVars);
+        $page = static::_getUrlComponents($urlInfo, self::_getOffset($urlInfo, 0), 'page', $userVars);
         return static::cleanFileVar($page ?? '');
     }
 
@@ -172,7 +185,7 @@ public static function getPage(string $urlInfo, array $userVars = []): string
      */
     public static function getOp(string $urlInfo, array $userVars = []): string
     {
-        $operation = static::_getUrlComponents($urlInfo, 1, 'op', $userVars);
+        $operation = static::_getUrlComponents($urlInfo, self::_getOffset($urlInfo, 1), 'op', $userVars);
         return static::cleanFileVar($operation ?: 'index');
     }
 
@@ -186,7 +199,7 @@ public static function getOp(string $urlInfo, array $userVars = []): string
      */
     public static function getArgs(string $urlInfo, array $userVars = []): array
     {
-        return static::_getUrlComponents($urlInfo, 2, 'path', $userVars);
+        return static::_getUrlComponents($urlInfo, self::_getOffset($urlInfo, 2), 'path', $userVars);
     }
 
     /**
@@ -452,6 +465,14 @@ private static function _getUrlComponents(string $urlInfo, int $offset, string $
         return $component;
     }
 
+    /**
+     * Get offset. Add 1 extra if localization present in URL
+     */
+    private static function _getOffset(string $urlInfo, int $varOffset): int
+    {
+        return $varOffset + (int) !!self::getLocalization($urlInfo);
+    }
+
     /**
      * Extract the class name from the given file path.
      *

classes/core/Dispatcher.php

@@ -223,6 +223,7 @@ public function setUserResolver(): void
      * @param array $params Optional set of name => value pairs to pass as user parameters
      * @param string $anchor Optional name of anchor to add to URL
      * @param bool $escape Whether or not to escape ampersands for this URL; default false.
+     * @param string $urlLocaleForPage Whether or not to override locale for this URL; Use '' to exclude.
      *
      * @return string the URL
      */
@@ -235,14 +236,15 @@ public function url(
         $path = null,
         $params = null,
         $anchor = null,
-        $escape = false
+        $escape = false,
+        ?string $urlLocaleForPage = null,
     ) {
         // Instantiate the requested router
         assert(isset($this->_routerNames[$shortcut]));
         $routerName = $this->_routerNames[$shortcut];
         $router = & $this->_instantiateRouter($routerName, $shortcut);
 
-        return $router->url($request, $newContext, $handler, $op, $path, $params, $anchor, $escape);
+        return $router->url($request, $newContext, $handler, $op, $path, $params, $anchor, $escape, $urlLocaleForPage);
     }
 
     //

classes/core/PKPPageRouter.php

@@ -20,6 +20,7 @@
 use APP\facades\Repo;
 use Illuminate\Support\Facades\Auth;
 use PKP\core\PKPSessionGuard;
+use PKP\context\Context;
 use PKP\facades\Locale;
 use PKP\plugins\Hook;
 use PKP\security\Role;
@@ -186,14 +187,16 @@ public function route($request)
         $op = $this->getRequestedOp($request);
 
         // If the application has not yet been installed we only
-        // allow installer pages to be displayed.
-        if (!Application::isInstalled()) {
-            if (!in_array($page, $this->getInstallationPages())) {
-                // A non-installation page was called although
-                // the system is not yet installed. Redirect to
-                // the installation page.
-                $request->redirect('index', 'install');
-            }
+        // allow installer pages to be displayed,
+        // or is installed and one of the installer pages was called
+        if (!Application::isInstalled() && !in_array($page, $this->getInstallationPages())) {
+            // A non-installation page was called although
+            // the system is not yet installed. Redirect to
+            // the installation page.
+            $request->redirect('index', 'install');
+        } else if (Application::isInstalled() && in_array($page, $this->getInstallationPages())) {
+            // Redirect to the index page
+            $request->redirect('index', 'index');
         }
 
         // Redirect requests from logged-out users to a context which is not
@@ -234,6 +237,14 @@ public function route($request)
             }
         }
 
+        // Set locale from URL or from 'setLocale'-op/search-params
+        $setLocale = ($op === 'setLocale'
+            ? ($this->getRequestedArgs($request)[0] ?? null)
+            : ($page === 'install'
+                ? ($_GET['setLocale'] ?? null)
+                : null));
+        $this->_setLocale($request, $setLocale);
+
         // Call the selected handler's index operation if
         // no operation was defined in the request.
         if (empty($op)) {
@@ -284,6 +295,7 @@ public function route($request)
      * @param null|mixed $path
      * @param null|mixed $params
      * @param null|mixed $anchor
+     * @param null|string $urlLocaleForPage
      */
     public function url(
         PKPRequest $request,
@@ -293,7 +305,8 @@ public function url(
         $path = null,
         $params = null,
         $anchor = null,
-        $escape = false
+        $escape = false,
+        ?string $urlLocaleForPage = null,
     ) {
         //
         // Base URL and Context
@@ -390,8 +403,14 @@ public function url(
         //
         // Assemble URL
         //
-        // Context, page, operation and additional path go into the path info.
+        // Context, locale?, page, operation and additional path go into the path info.
         $pathInfoArray = $context;
+        if ($urlLocaleForPage !== '') {
+            [$contextObject, $contextLocales] = $this->_getContextAndLocales($request, $context[0] ?? "");
+            if (count($contextLocales) > 1) {
+                $pathInfoArray[] = $this->_getLocaleForUrl($request, $contextObject, $contextLocales, $urlLocaleForPage);
+            }
+        }
         if (!empty($page)) {
             $pathInfoArray[] = $page;
             if (!empty($op)) {
@@ -495,6 +514,75 @@ private function _getRequestedUrlParts($callback, $request): array|string|null
         $userVars = $request->getUserVars();
         return $callback($url ?? '', $userVars);
     }
+
+    /**
+     * Get context object and context/site/all locales.
+     */
+    private function _getContextAndLocales(PKPRequest $request, string $contextPath): array
+    {
+        return [
+            $context = $this->getCurrentContext() ?? (($contextPath === 'index' || !$contextPath || $contextPath === Application::CONTEXT_ID_ALL)
+                ? null
+                : Application::getContextDAO()->getByPath($contextPath)),
+            $context?->getSupportedLocales()
+                ?? (($contextPath === 'index')
+                    ? (Application::isInstalled()
+                        ? $request->getSite()->getSupportedLocales()
+                        : array_keys(Locale::getLocales()))
+                    : [])
+        ];
+    }
+
+    /**
+     * Get locale for URL from session or primary
+     */
+    private function _getLocaleForUrl(PKPRequest $request, ?Context $context, array $locales, ?string $urlLocaleForPage): string
+    {
+        return in_array($locale = $urlLocaleForPage ?: Locale::getLocale(), $locales)
+            ? $locale
+            : (($context ?? $request->getSite())?->getPrimaryLocale() ?? Locale::getLocale());
+    }
+
+    /**
+     * Change the locale for the current user.
+     * Redirect to url with(out) locale if locale changed or context set to multi/monolingual.
+     */
+    private function _setLocale(PKPRequest $request, ?string $setLocale): void
+    {
+        $contextPath = $this->_getRequestedUrlParts(['Core', 'getContextPath'], $request);
+        $urlLocale = $this->_getRequestedUrlParts(['Core', 'getLocalization'], $request);
+        $multiLingual = count($this->_getContextAndLocales($request, $contextPath)[1]) > 1;
+
+        if (!$multiLingual && !$urlLocale && !$setLocale || $multiLingual && !$setLocale && $urlLocale === Locale::getLocale()) {
+            return;
+        }
+
+        $sessionLocale = (function (string $l) use ($request): string {
+            $session = $request->getSession();
+            if (Locale::isSupported($l) && $l !== $session->get('currentLocale')) {
+                $session->put('currentLocale', $l);
+                $request->setCookieVar('currentLocale', $l);
+            }
+            // In case session current locale has been set to non-supported locale, or is null, somewhere else
+            if (!Locale::isSupported($session->get('currentLocale') ?? "")) {
+                $session->put('currentLocale', Locale::getLocale());
+                $request->setCookieVar('currentLocale', Locale::getLocale());
+            }
+            return $session->get('currentLocale');
+        })($setLocale ?? $urlLocale);
+
+        if (preg_match('#^/\w#', $source = $request->getUserVar('source') ?? "")) {
+            $request->redirectUrl($source);
+        }
+
+        $uri = Core::removeBaseUrl($setLocale ? ($_SERVER['HTTP_REFERER'] ?? "") : ($_SERVER['REQUEST_URI'] ?? ""));
+        $newUrlLocale = $multiLingual ? $sessionLocale . "/" : "";
+        $pathInfo = ($uri)
+            ? preg_replace("#^/$contextPath" . ($urlLocale ? "/$urlLocale" : "") . "(/|$)#", "/$contextPath/$newUrlLocale", $uri, 1)
+            : "/index/$newUrlLocale";
+
+        $request->redirectUrl($this->getIndexUrl($request) . $pathInfo);
+    }
 }
 
 if (!PKP_STRICT_MODE) {

classes/core/PKPRequest.php

@@ -774,11 +774,12 @@ public function setCookieVar($key, $value, $expire = 0)
      * @param mixed $path string or array containing path info for redirect.
      * @param array $params Map of name => value pairs for additional parameters
      * @param string $anchor Name of desired anchor on the target page
+     * @param string $urlLocaleForPage Whether or not to override locale for this URL; Use '' to exclude.
      */
-    public function redirect($context = null, $page = null, $op = null, $path = null, $params = null, $anchor = null)
+    public function redirect($context = null, $page = null, $op = null, $path = null, $params = null, $anchor = null, ?string $urlLocaleForPage = null)
     {
         $dispatcher = $this->getDispatcher();
-        $this->redirectUrl($dispatcher->url($this, PKPApplication::ROUTE_PAGE, $context, $page, $op, $path, $params, $anchor));
+        $this->redirectUrl($dispatcher->url($this, PKPApplication::ROUTE_PAGE, $context, $page, $op, $path, $params, $anchor, false, $urlLocaleForPage));
     }
 
     /**

classes/core/PKPRouter.php

@@ -104,6 +104,14 @@ public function setApplication(Application $application)
         $this->_application = $application;
     }
 
+    /**
+     * get the current context
+     */
+    public function getCurrentContext(): ?Context
+    {
+        return $this->_context;
+    }
+
     /**
      * get the dispatcher
      */

classes/observers/events/UsageEvent.php

@@ -156,7 +156,8 @@ protected function getRouterCanonicalUrl(Request $request, string $canonicalUrlP
             null,
             $canonicalUrlPage,
             $canonicalUrlOp,
-            $canonicalUrlParams
+            $canonicalUrlParams,
+            urlLocaleForPage: ''
         );
 
         // Make sure we log the server name and not aliases.

classes/template/PKPTemplateManager.php

@@ -278,6 +278,18 @@ public function initialize($request)
                         $this->addHeader('customHeaders', $customHeaders);
                     }
                 }
+
+                if (count($supportedLocales = $currentContext?->getSupportedLocales() ?? $site->getSupportedLocales()) > 1) {
+                    (function () use ($request, $router, $supportedLocales) {
+                        $page = $router->getRequestedPage($request);
+                        $op = $router->getRequestedOp($request);
+                        $path = $router->getRequestedArgs($request);
+                        $url = fn (string $locale = ""): string => $router->url($request, null, $page, $op, $path, urlLocaleForPage: $locale);
+                        collect($supportedLocales)
+                            ->each(fn (string $l) => $this->addHeader("language-$l", "<link rel='alternate' hreflang='" . str_replace(['_', '@cyrillic', '@latin'], ['-', '-Cyrl', '-Latn'], $l) . "' href='" . $url($l) . "' />"));
+                        $this->addHeader("language-xdefault", "<link rel='alternate' hreflang='x-default' href='" . $url() . "' />");
+                    })();
+                }
             }
 
             if ($currentContext && !$currentContext->getEnabled()) {
@@ -1779,8 +1791,8 @@ public function smartyUrl($parameters, $smarty)
         // Extract the reserved variables named in $paramList, and remove them
         // from the parameters array. Variables remaining in parameters will be passed
         // along to Request::url as extra parameters.
-        $params = $router = $page = $component = $anchor = $escape = $op = $path = null;
-        $paramList = ['params', 'router', 'context', 'page', 'component', 'op', 'path', 'anchor', 'escape'];
+        $params = $router = $page = $component = $anchor = $escape = $op = $path = $urlLocaleForPage = null;
+        $paramList = ['params', 'router', 'context', 'page', 'component', 'op', 'path', 'anchor', 'escape', 'urlLocaleForPage'];
         foreach ($paramList as $parameter) {
             if (isset($parameters[$parameter])) {
                 $$parameter = $parameters[$parameter];
@@ -1823,7 +1835,7 @@ public function smartyUrl($parameters, $smarty)
                 assert(false);
         }
         // Let the dispatcher create the url
-        return $dispatcher->url($this->_request, $router, $context, $handler, $op, $path, $parameters, $anchor, !isset($escape) || $escape);
+        return $dispatcher->url($this->_request, $router, $context, $handler, $op, $path, $parameters, $anchor, !isset($escape) || $escape, $urlLocaleForPage);
     }
 
     /**

cypress/support/commands.js

@@ -125,7 +125,7 @@ Cypress.Commands.add('install', function() {
 Cypress.Commands.add('login', (username, password, context) => {
 	context = context || 'index';
 	password = password || (username + username);
-	cy.visit('index.php/' + context + '/login/signIn', {
+	cy.visit('index.php/' + context + '/en/login/signIn', {
 		method: 'POST',
 		body: {username: username, password: password}
 	});

pages/user/PKPUserHandler.php

@@ -35,38 +35,6 @@ public function index($args, $request)
         $request->redirect(null, null, 'profile');
     }
 
-    /**
-     * Change the locale for the current user.
-     *
-     * @param array $args first parameter is the new locale
-     */
-    public function setLocale($args, $request)
-    {
-        $setLocale = array_shift($args);
-
-        $site = $request->getSite();
-        $context = $request->getContext();
-        if ($context != null) {
-            $contextSupportedLocales = (array) $context->getSupportedLocales();
-        }
-
-        if (Locale::isLocaleValid($setLocale) && (!isset($contextSupportedLocales) || in_array($setLocale, $contextSupportedLocales)) && in_array($setLocale, $site->getSupportedLocales())) {
-            $session = $request->getSession();
-            $session->put('currentLocale', $setLocale);
-        }
-
-        $source = $request->getUserVar('source');
-        if (preg_match('#^/\w#', $source) === 1) {
-            $request->redirectUrl($source);
-        }
-
-        if (isset($_SERVER['HTTP_REFERER'])) {
-            $request->redirectUrl($_SERVER['HTTP_REFERER']);
-        }
-
-        $request->redirect(null, 'index');
-    }
-
     /**
      * Get interests for reviewer interests autocomplete.
      *

plugins/generic/usageEvent/PKPUsageEventPlugin.php

@@ -253,7 +253,8 @@ protected function buildUsageEvent($hookName, $args)
             null,
             $canonicalUrlPage,
             $canonicalUrlOp,
-            $canonicalUrlParams
+            $canonicalUrlParams,
+            urlLocaleForPage: ''
         );
 
         // Make sure we log the server name and not aliases.
@@ -309,7 +310,7 @@ protected function buildUsageEvent($hookName, $args)
         }
 
         // Service URI.
-        $serviceUri = $router->url($request, $context->getPath());
+        $serviceUri = $router->url($request, $context->getPath(), urlLocaleForPage: '');
 
         // IP and Host.
         $ip = $request->getRemoteAddr();