feat: localize jwt.io banner japanese

server.js

@@ -18,22 +18,41 @@ if (process.env.NODE_ENV === "production") {
     );
 }
 
+app.use((req, res, next) => {
+    const acceptLanguage = req.headers['accept-language'];
+
+    if(acceptLanguage){
+        const preferredLanguage = acceptLanguage.split(",")[0].split("-")[0];
+
+        req.preferredLanguage = preferredLanguage;
+    }else{
+        req.preferredLanguage = 'en';
+    }
+
+    next();
+})
+
 app.use((req, res, next) => {
     res.locals.COOKIE_CONSENT_DOMAIN_ID = process.env.COOKIE_CONSENT_DOMAIN_ID;
     next();
 });
 app.use(express.static("dist/website"));
 app.get("/", function(req, res) {
-    res.render("index");
+    res.render("index", {
+        preferredLanguage: req.preferredLanguage,
+    });
 });
 
 app.get("/introduction", function(req, res) {
-    res.render("introduction");
+    res.render("introduction", {
+        preferredLanguage: req.preferredLanguage,
+    });
 });
 
 app.get("/libraries", function(req, res) {
     res.render("libraries", {
-        languages: languages
+        languages: languages,
+        preferredLanguage: req.preferredLanguage,
     });
 });
 
@@ -44,4 +63,4 @@ app.get("/home", function(req, res) {
 
 app.listen(process.env.PORT || 3000, function() {
     console.log("Started.");
-});
+});

views/website/navigation.pug

@@ -1,8 +1,12 @@
 .top-banner-bg.closed
 .top-banner.closed
   .top-banner-container
-    a(href="https://a0.to/jwt-io-feedback" target="_blank") Get an exclusive look at jwt.io v2 and help us shape its final form with your feedback.
-      span(aria-hiden="true") →
+    if preferredLanguage === 'ja'
+      a(href="https://a0.to/jwt-io-feedback-ja" target="_blank") jwt.io v2ベータバージョン: フィードバックをお寄せください。
+        span(aria-hiden="true") →
+    else
+      a(href="https://a0.to/jwt-io-feedback" target="_blank") Get an exclusive look at jwt.io v2 and help us shape its final form with your feedback.
+        span(aria-hiden="true") →
     button.close-top-banner +
 
 nav.navbar