feature: i18n

components/a.js

@@ -1,11 +1,13 @@
 import Link from "next/link";
+import config from "../lib/config.mjs";
 
 const A = props => {
   return (
     <Link
       {...props}
       className="no-underline hover:underline text-black dark:text-white font-normal cursor-pointer"
       target={props.self ? "_self" : "_blank"}
+      locale={config.defaultLocale}
     />
   );
 };

components/blog.js

@@ -13,8 +13,19 @@ import Disqus from "./disqus";
 import Comments from "./comments";
 
 export default withView(props => {
-  const { children, title, date, author, view, id, tags, pageURL, image } =
-    props;
+  const {
+    children,
+    title,
+    date,
+    author,
+    view,
+    id,
+    tags,
+    pageURL,
+    image,
+    i18n,
+    locale,
+  } = props;
   const [replies, setReplies] = useState([]);
   const [likes, setLikes] = useState([]);
 
@@ -75,8 +86,26 @@ export default withView(props => {
               </Link>
             </div>
             <div className="flex-1" />
+            {i18n?.length > 1 && (
+              <>
+                {i18n
+                  .filter(language => language !== locale)
+                  .map(language => {
+                    return (
+                      <Link
+                        className="mr-2 no-underline"
+                        key={language}
+                        href={id}
+                        locale={language}
+                      >
+                        <small>🌐 {language.toUpperCase()}</small>
+                      </Link>
+                    );
+                  })}
+              </>
+            )}
             <div className={`justify-end ${withImageColor}`} id="views">
-              {view > 0 && <small>{view} views</small>}
+              {view > 10 && <small>{view} views</small>}
             </div>
           </div>
         )}

components/header.js

@@ -86,12 +86,15 @@ export default function Header({
           type="application/ld+json"
           dangerouslySetInnerHTML={{ __html: structuredData }}
         />
-        <link
-          rel="alternate"
-          type="application/atom+xml"
-          title={siteTitle}
-          href={config.feedPath}
-        />
+        {config.locales.map(locale => (
+          <link
+            key={locale}
+            rel="alternate"
+            type="application/atom+xml"
+            title={`${siteTitle} - ${siteDescription} (${locale})`}
+            href={`/${locale}/${config.feedFile}`}
+          />
+        ))}
         {enableAdsense && <Adsense />}
       </Head>
       {image && (

components/tag.js

@@ -1,4 +1,5 @@
 import Link from "next/link";
+import config from "../lib/config.mjs";
 
 export default function Tag(props) {
   const highlight = props.highlight
@@ -8,6 +9,7 @@ export default function Tag(props) {
     <Link
       href={`/tag/${props.tag.toLowerCase().trim()}`}
       className="no-underline"
+      locale={config.defaultLocale}
     >
       <span
         className={`before:content-['#'] duration-100 transition rounded inline-block p-1 mx-1 text-sm font-mono ${highlight}`}

lib/config.mjs

@@ -1,11 +1,14 @@
-// eslint-disable-next-line import/no-anonymous-default-export
+import nextConfig from "../next.config.js";
+
 const config = {
   siteTitle: "Lawrence Li",
   authorName: "Lawrence",
   domain: "lawrenceli.me",
   authorEmail: "[email protected]",
   baseURL: "https://lawrenceli.me",
-  feedPath: "/atom.xml",
+  defaultLocale: nextConfig.i18n.defaultLocale,
+  locales: nextConfig.i18n.locales,
+  feedFile: "atom.xml",
   feedItemsCount: 10,
   siteDescription: "Blog",
   activityPubUser: "lawrence",

lib/feed.mjs

@@ -4,38 +4,52 @@ import {
   defaultMarkdownDirectory,
 } from "./ssg.mjs";
 import config from "./config.mjs";
+import fs from "node:fs";
 
 const {
-  siteTitle,
   authorName,
   authorEmail,
   baseURL,
-  websubHub,
+  defaultLocale,
+  feedFile,
   feedItemsCount,
+  siteTitle,
+  siteDescription,
+  websubHub,
+  locales,
 } = config;
 
 // https://datatracker.ietf.org/doc/html/rfc4287
 const buildFeed = async () => {
   const markdownData = getMdPostsData();
   const postContents = await Promise.all(
     markdownData.map(async item => {
-      return await getMdContentById(item.id, defaultMarkdownDirectory);
+      return await getMdContentById(item.fileName, defaultMarkdownDirectory);
     }),
   );
-  // only output the recent blog posts
-  const feed = createRSS(
-    postContents.slice(0, Math.min(feedItemsCount, postContents.length)),
-  );
-  console.log(feed);
+  locales.forEach(locale => {
+    console.log("Building feed for", locale);
+    const feed = createRSS(postContents, locale);
+    const fileName = `./public/atom.${locale}.xml`;
+    fs.openSync(fileName, "w");
+    fs.writeFileSync(fileName, feed);
+    if (locale === defaultLocale) {
+      // just an alternate for default locale feed (to keep old link working)
+      fs.writeFileSync(`./public/${feedFile}`, feed);
+    }
+  });
 };
 
 function mapToAtomEntry(post) {
   const categories = post.tags?.split(",");
-  return `
-    <entry>
+  let postLink = `${baseURL}/${post.locale}/blog/${post.id}`;
+  if (post.locale === defaultLocale) {
+    postLink = `${baseURL}/blog/${post.id}`;
+  }
+  return `<entry>
       <title>${decode(post.title)}</title>
-      <id>${baseURL}/blog/${post.id}</id>
-      <link href="${baseURL}/blog/${post.id}"/>
+      <id>${postLink}</id>
+      <link href="${postLink}"/>
       <published>${post.date}T00:00:00.000Z</published>
       <updated>${
         post.modified ? post.modified : post.date
@@ -63,13 +77,21 @@ function decode(string) {
     .replace(/'/g, "&apos;");
 }
 
-function createRSS(blogPosts = []) {
-  const postsString = blogPosts.map(mapToAtomEntry).reduce((a, b) => a + b, "");
+function createRSS(blogPosts, locale) {
+  const postsString = blogPosts
+    .filter(post => post.locale === locale)
+    .map(mapToAtomEntry)
+    .slice(0, Math.min(feedItemsCount, blogPosts.length))
+    .reduce((a, b) => a + b, "");
+  let feedURL = `${baseURL}/${locale}/${feedFile}`;
+  if (locale === defaultLocale) {
+    feedURL = `${baseURL}/${feedFile}`;
+  }
   return `<?xml version="1.0" encoding="utf-8"?>
   <feed xmlns="http://www.w3.org/2005/Atom">
     <title>${siteTitle}</title>
-    <subtitle>Blog</subtitle>
-    <link href="${baseURL}/atom.xml" rel="self" type="application/atom+xml" />
+    <subtitle>${siteDescription}</subtitle>
+    <link href="${feedURL}" rel="self" type="application/atom+xml" />
     <link href="${websubHub}" rel="hub" />
     <link href="${baseURL}/"/>
     <id>${baseURL}/</id>

lib/ssg.mjs

@@ -39,18 +39,36 @@ export const getMdPostsData = mdDirectory => {
     .filter(fileName => fileName.includes(".md"))
     .map(mdPostName => {
       const id = mdPostName.replace(/\.md$/, "");
+      const locale = id.includes(".") ? id.split(".")[1] : config.defaultLocale;
+      const idWithoutLocale = id.replace(`.${locale}`, "");
       const fullPath = path.join(mdDirectory, mdPostName);
       const mdContent = fs.readFileSync(fullPath, "utf8");
       const matterResult = matter(mdContent);
       return {
-        id,
+        id: idWithoutLocale,
+        fileName: id,
+        locale,
         ...matterResult.data,
         content: matterResult.content,
       };
     });
   return mdPostsData.sort(sortByDate).filter(filterVisibility);
 };
 
+const getI18nLanguagesByTitle = (i18nTitle, mdPostNames) => {
+  const languages = new Set();
+  mdPostNames.forEach(fileName => {
+    if (fileName.startsWith(i18nTitle)) {
+      if (fileName.split(".")[1] === "md") {
+        languages.add(config.defaultLocale);
+      } else {
+        languages.add(fileName.split(".")[1]);
+      }
+    }
+  });
+  return [...languages];
+};
+
 export const getMdContentById = (id, mdDirectory, withHTMLString = true) => {
   // default using the `./posts` for markdown directory
   if (!mdDirectory) {
@@ -59,22 +77,35 @@ export const getMdContentById = (id, mdDirectory, withHTMLString = true) => {
   const isBlog = mdDirectory === defaultMarkdownDirectory; // if the markdown is blog article
   const mdPostNames = fs.readdirSync(mdDirectory);
   const mdPostsData = mdPostNames
-    .filter(name => name === id + ".md")
+    .filter(fileName => {
+      if (fileName.includes(`.${config.defaultLocale}`)) {
+        return fileName === id + ".md";
+      }
+      return fileName === id.replace(`.${config.defaultLocale}`, "") + ".md";
+    })
     .map(async mdPostName => {
       const fullPath = path.join(mdDirectory, mdPostName);
       const mdContent = fs.readFileSync(fullPath, "utf8");
       const fileStat = fs.statSync(fullPath);
       const matterResult = matter(mdContent);
+      const locale = id.includes(".") ? id.split(".")[1] : config.defaultLocale;
+      const idWithoutLocale = id.replace(`.${locale}`, "");
+      const languages = getI18nLanguagesByTitle(
+        mdPostName.split(".")[0],
+        mdPostNames,
+      ).filter(language => config.locales.includes(language));
       const htmlResult = await renderHTMLfromMarkdownString(
         matterResult.content,
         isBlog,
       );
       return {
-        id,
+        id: idWithoutLocale,
         birthTime: fileStat.birthtime.toISOString(),
         // modifiedTime: fileStat.mtime.toISOString(),
         author: config.authorName, // dafult authorName
         // content: matterResult.content, // original markdown string
+        i18n: languages,
+        locale,
         htmlStringContent: withHTMLString ? htmlResult.value : "", // rendered html string
         htmlAst: isBlog
           ? fromHtml(htmlResult.value, {

lib/websub.mjs

@@ -1,8 +1,8 @@
 import config from "./config.mjs";
 import { getMdPostsData } from "./ssg.mjs";
 
-const { websubHub, baseURL, feedPath } = config;
-const URL = baseURL + feedPath;
+const { websubHub, baseURL, feedFile } = config;
+const URL = baseURL + "/" + feedFile;
 
 /**
  * Determine if we need to publish the websub.

middleware.js

@@ -1,4 +1,5 @@
 import { NextResponse } from "next/server";
+import cfg from "./lib/config.mjs";
 
 // This function can be marked `async` if using `await` inside
 export function middleware(req) {
@@ -11,6 +12,11 @@ export function middleware(req) {
       new URL(`/api/activitypub/blog/${blogId}`, req.url),
     );
   }
+  // RSS Feed i18n
+  if (path.endsWith(cfg.feedFile)) {
+    const locale = req.nextUrl.locale;
+    return NextResponse.rewrite(new URL(`/atom.${locale}.xml`, req.url));
+  }
 }
 
 // export const config = {

next.config.js

@@ -1,12 +1,14 @@
 // next.config.js
+
 module.exports = {
   // experimental: {
   //   appDir: true,
   // },
-  // i18n: {
-  //   locales: ["zh"],
-  //   defaultLocale: "zh",
-  // },
+  i18n: {
+    locales: ["zh"], // post.en.md, post.ja.md
+    defaultLocale: "zh", // post.zh.md or post.md
+    localeDetection: false,
+  },
   transpilePackages: ["react-tweet"],
   async headers() {
     return [
@@ -27,11 +29,11 @@ module.exports = {
         source: "/.well-known/:param",
         destination: "/api/.well-known/:param",
       },
-      {
-        source: "/feed",
-        destination: "/atom.xml",
-      },
-
+      // {
+      //   source: "/:locale/atom.xml",
+      //   destination: "/atom.:locale.xml",
+      //   locale: false,
+      // },
       // {
       //   source: "/blog/:path",
       //   has: [

package.json

@@ -4,7 +4,7 @@
   "markdown": "github",
   "scripts": {
     "dev": "pnpm feed && next dev -H 0.0.0.0",
-    "feed": "node ./lib/feed.mjs > ./public/atom.xml",
+    "feed": "node ./lib/feed.mjs",
     "websub": "node ./lib/websub.mjs",
     "start": "next start",
     "build": "NEXT_PUBLIC_BUILDTIME=$(date '+%s') next build && pnpm feed && next-sitemap",

pages/blog/[id].js

@@ -8,6 +8,7 @@ import path from "path";
 import { lazy } from "react";
 import { Fragment, jsx, jsxs } from "react/jsx-runtime";
 import { toJsxRuntime } from "hast-util-to-jsx-runtime";
+import config from "../../lib/config.mjs";
 const Douban = lazy(() => import("../../components/douban"));
 const Bilibili = lazy(() => import("../../components/bilibili"));
 const Tweet = lazy(() => import("../../components/twitter"));
@@ -40,7 +41,11 @@ export default PathId;
 
 export const getStaticProps = async context => {
   const { id } = context.params;
-  const mdData = await getMdContentById(id, defaultMarkdownDirectory, false);
+  const mdData = await getMdContentById(
+    `${id}.${context.locale}`,
+    defaultMarkdownDirectory,
+    false,
+  );
   return {
     props: mdData,
   };
@@ -50,11 +55,14 @@ export const getStaticPaths = async () => {
   const mdPostsData = getMdPostsData(path.join(process.cwd(), "posts"));
   const paths = mdPostsData.map(data => {
     return {
-      params: data,
+      params: { id: data.id },
+      locale: config.locales.includes(data.locale)
+        ? data.locale
+        : config.defaultLocale,
     };
   });
   // const paths = [
-  //   { params: { id: "hi" } },
+  //   { params: { id: "hi" }, locale: "zh" },
   // ];
   return {
     paths,