per-locale bundle & inline locale (#16369)

* feat: split entry file by locale name

* chore: とりあえず transform hook で雑に分割

* chore: とりあえず transform 結果をいい感じに

* chore: concurrent buildで高速化

* chore: vite ではローケルのないものをビルドして後処理でどうにかするように

* chore: 後処理のためにi18n.jを単体になるように切り出す

* chore: use typescript

* chore: remove unref(i18n) in vite build process

* chore: inline variable

* fix: build error

* fix: i18n.ts.something.replaceAll() become error

* chore: ignore export specifier from error

* chore: support i18n.tsx as object

* chore: process literal for all files

* chore: split config and locale

* chore: inline locale name

* chore: remove updating locale in boot common

* chore: use top-level await to load locales

* chore: inline locale

* chore: remove loading locale from boot.js

* chore: remove loading locale from boot.js

* コメント追加

* fix test; fetchに失敗する

* import削除ログをdebugレベルに

* fix: watch pug

* chore: use hash for entry files

* chore: remove es-module-lexer from dependencies

* chore: move to frontend-builder

* chore: use inline locale in embed

* chore: refetch json on hot reload

* feat: store localization related to boot.js in backend in bootloaderLocales localstorage

* 応急処置を戻す

* fix spex

* fix `Using i18n identifier "e" directly. Skipping inlining.` warning

* refactor: use scriptsDir parameter

* chore: remove i18n from depmap

* chore: make build crash if errors

* error -> warn few conditions

* use inline object

* update localstorage keys

* remove accessing locale localstorage

* fix: failed to process i18n.tsx.aaa({x:i18n.bbb})

4 files changed, 75 insertions, 107 deletions

diff --git a/packages/backend/src/server/web/boot.embed.js b/packages/backend/src/server/web/boot.embed.js
index 9de1275380..022ff064ad 100644
--- a/packages/backend/src/server/web/boot.embed.js
+++ b/packages/backend/src/server/web/boot.embed.js
@@ -32,61 +32,30 @@
 	}
 
 	//#region Detect language & fetch translations
-	if (!localStorage.hasOwnProperty('locale')) {
-		const supportedLangs = LANGS;
-		let lang = localStorage.getItem('lang');
-		if (lang == null || !supportedLangs.includes(lang)) {
-			if (supportedLangs.includes(navigator.language)) {
-				lang = navigator.language;
-			} else {
-				lang = supportedLangs.find(x => x.split('-')[0] === navigator.language);
-
-				// Fallback
-				if (lang == null) lang = 'en-US';
-			}
-		}
-
-		const metaRes = await window.fetch('/api/meta', {
-			method: 'POST',
-			body: JSON.stringify({}),
-			credentials: 'omit',
-			cache: 'no-cache',
-			headers: {
-				'Content-Type': 'application/json',
-			},
-		});
-		if (metaRes.status !== 200) {
-			renderError('META_FETCH');
-			return;
-		}
-		const meta = await metaRes.json();
-		const v = meta.version;
-		if (v == null) {
-			renderError('META_FETCH_V');
-			return;
-		}
+	const supportedLangs = LANGS;
+	/** @type { string } */
+	let lang = localStorage.getItem('lang');
+	if (lang == null || !supportedLangs.includes(lang)) {
+		if (supportedLangs.includes(navigator.language)) {
+			lang = navigator.language;
+		} else {
+			lang = supportedLangs.find(x => x.split('-')[0] === navigator.language);
 
-		// for https://github.com/misskey-dev/misskey/issues/10202
-		if (lang == null || lang.toString == null || lang.toString() === 'null') {
-			console.error('invalid lang value detected!!!', typeof lang, lang);
-			lang = 'en-US';
+			// Fallback
+			if (lang == null) lang = 'en-US';
 		}
+	}
 
-		const localRes = await window.fetch(`/assets/locales/${lang}.${v}.json`);
-		if (localRes.status === 200) {
-			localStorage.setItem('lang', lang);
-			localStorage.setItem('locale', await localRes.text());
-			localStorage.setItem('localeVersion', v);
-		} else {
-			renderError('LOCALE_FETCH');
-			return;
-		}
+	// for https://github.com/misskey-dev/misskey/issues/10202
+	if (lang == null || lang.toString == null || lang.toString() === 'null') {
+		console.error('invalid lang value detected!!!', typeof lang, lang);
+		lang = 'en-US';
 	}
 	//#endregion
 
 	//#region Script
 	async function importAppScript() {
-		await import(`/embed_vite/${CLIENT_ENTRY}`)
+		await import(CLIENT_ENTRY ? `/embed_vite/${CLIENT_ENTRY.replace('scripts', lang)}` : '/embed_vite/src/_boot_.ts')
 			.catch(async e => {
 				console.error(e);
 				renderError('APP_IMPORT');
@@ -115,10 +84,26 @@
 			await new Promise(resolve => window.addEventListener('DOMContentLoaded', resolve));
 		}
 
-		const locale = JSON.parse(localStorage.getItem('locale') || '{}');
+		let messages = null;
+		const bootloaderLocales = localStorage.getItem('bootloaderLocales');
+		if (bootloaderLocales) {
+			messages = JSON.parse(bootloaderLocales);
+		}
+		if (!messages) {
+			// older version of misskey does not store bootloaderLocales, stores locale as a whole
+			const legacyLocale = localStorage.getItem('locale');
+			if (legacyLocale) {
+				const parsed = JSON.parse(legacyLocale);
+				messages = {
+					...(parsed._bootErrors ?? {}),
+					reload: parsed.reload,
+				};
+			}
+		}
+		if (!messages) messages = {};
 
-		const title = locale?._bootErrors?.title || 'Failed to initialize Misskey';
-		const reload = locale?.reload || 'Reload';
+		const title = messages?.title || 'Failed to initialize Misskey';
+		const reload = messages?.reload || 'Reload';
 
 		document.body.innerHTML = `<svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" class="icon"><path stroke="none" d="M0 0h24v24H0z" fill="none"/><path d="M12 12m-9 0a9 9 0 1 0 18 0a9 9 0 1 0 -18 0" /><path d="M12 9v4" /><path d="M12 16v.01" /></svg>
 		<div class="message">${title}</div>
diff --git a/packages/backend/src/server/web/boot.js b/packages/backend/src/server/web/boot.js
index 1a30e9ed2b..0c0b46f82b 100644
--- a/packages/backend/src/server/web/boot.js
+++ b/packages/backend/src/server/web/boot.js
@@ -22,62 +22,31 @@
 		return;
 	}
 
-	//#region Detect language & fetch translations
-	if (!localStorage.hasOwnProperty('locale')) {
-		const supportedLangs = LANGS;
-		let lang = localStorage.getItem('lang');
-		if (lang == null || !supportedLangs.includes(lang)) {
-			if (supportedLangs.includes(navigator.language)) {
-				lang = navigator.language;
-			} else {
-				lang = supportedLangs.find(x => x.split('-')[0] === navigator.language);
-
-				// Fallback
-				if (lang == null) lang = 'en-US';
-			}
-		}
-
-		const metaRes = await window.fetch('/api/meta', {
-			method: 'POST',
-			body: JSON.stringify({}),
-			credentials: 'omit',
-			cache: 'no-cache',
-			headers: {
-				'Content-Type': 'application/json',
-			},
-		});
-		if (metaRes.status !== 200) {
-			renderError('META_FETCH');
-			return;
-		}
-		const meta = await metaRes.json();
-		const v = meta.version;
-		if (v == null) {
-			renderError('META_FETCH_V');
-			return;
-		}
+	//#region Detect language
+	const supportedLangs = LANGS;
+	/** @type { string } */
+	let lang = localStorage.getItem('lang');
+	if (lang == null || !supportedLangs.includes(lang)) {
+		if (supportedLangs.includes(navigator.language)) {
+			lang = navigator.language;
+		} else {
+			lang = supportedLangs.find(x => x.split('-')[0] === navigator.language);
 
-		// for https://github.com/misskey-dev/misskey/issues/10202
-		if (lang == null || lang.toString == null || lang.toString() === 'null') {
-			console.error('invalid lang value detected!!!', typeof lang, lang);
-			lang = 'en-US';
+			// Fallback
+			if (lang == null) lang = 'en-US';
 		}
+	}
 
-		const localRes = await window.fetch(`/assets/locales/${lang}.${v}.json`);
-		if (localRes.status === 200) {
-			localStorage.setItem('lang', lang);
-			localStorage.setItem('locale', await localRes.text());
-			localStorage.setItem('localeVersion', v);
-		} else {
-			renderError('LOCALE_FETCH');
-			return;
-		}
+	// for https://github.com/misskey-dev/misskey/issues/10202
+	if (lang == null || lang.toString == null || lang.toString() === 'null') {
+		console.error('invalid lang value detected!!!', typeof lang, lang);
+		lang = 'en-US';
 	}
 	//#endregion
 
 	//#region Script
 	async function importAppScript() {
-		await import(`/vite/${CLIENT_ENTRY}`)
+		await import(CLIENT_ENTRY ? `/vite/${CLIENT_ENTRY.replace('scripts', lang)}` : '/vite/src/_boot_.ts')
 			.catch(async e => {
 				console.error(e);
 				renderError('APP_IMPORT', e);
@@ -162,9 +131,25 @@
 			await new Promise(resolve => window.addEventListener('DOMContentLoaded', resolve));
 		}
 
-		const locale = JSON.parse(localStorage.getItem('locale') || '{}');
+		let messages = null;
+		const bootloaderLocales = localStorage.getItem('bootloaderLocales');
+		if (bootloaderLocales) {
+			messages = JSON.parse(bootloaderLocales);
+		}
+		if (!messages) {
+			// older version of misskey does not store bootloaderLocales, stores locale as a whole
+			const legacyLocale = localStorage.getItem('locale');
+			if (legacyLocale) {
+				const parsed = JSON.parse(legacyLocale);
+				messages = {
+					...(parsed._bootErrors ?? {}),
+					reload: parsed.reload,
+				};
+			}
+		}
+		if (!messages) messages = {};
 
-		const messages = Object.assign({
+		messages = Object.assign({
 			title: 'Failed to initialize Misskey',
 			solution: 'The following actions may solve the problem.',
 			solution1: 'Update your os and browser',
@@ -176,8 +161,8 @@
 			otherOption2: 'Start the simple client',
 			otherOption3: 'Start the repair tool',
 			otherOption4: 'Start Misskey in safe mode',
-		}, locale?._bootErrors || {});
-		const reload = locale?.reload || 'Reload';
+			reload: 'Reload',
+		}, messages);
 
 		const safeModeUrl = new URL(window.location.href);
 		safeModeUrl.searchParams.set('safemode', 'true');
@@ -193,7 +178,7 @@
 			</svg>
 			<h1>${messages.title}</h1>
 			<button class="button-big" onclick="location.reload(true);">
-				<span class="button-label-big">${reload}</span>
+				<span class="button-label-big">${messages?.reload}</span>
 			</button>
 			<p><b>${messages.solution}</b></p>
 			<p>${messages.solution1}</p>
diff --git a/packages/backend/src/server/web/views/base-embed.pug b/packages/backend/src/server/web/views/base-embed.pug
index baa0909676..29de86b8b6 100644
--- a/packages/backend/src/server/web/views/base-embed.pug
+++ b/packages/backend/src/server/web/views/base-embed.pug
@@ -19,7 +19,6 @@ html(class='embed')
 		meta(name='format-detection' content='telephone=no,date=no,address=no,email=no,url=no')
 		link(rel='icon' href= icon || '/favicon.ico')
 		link(rel='apple-touch-icon' href= appleTouchIcon || '/apple-touch-icon.png')
-		link(rel='modulepreload' href=`/embed_vite/${entry.file}`)
 
 		if !config.frontendEmbedManifestExists
 				script(type="module" src="/embed_vite/@vite/client")
@@ -40,7 +39,7 @@ html(class='embed')
 
 		script.
 			var VERSION = "#{version}";
-			var CLIENT_ENTRY = "#{entry.file}";
+			var CLIENT_ENTRY = !{JSON.stringify(entry.file)};
 
 		script(type='application/json' id='misskey_meta' data-generated-at=now)
 			!= metaJson
diff --git a/packages/backend/src/server/web/views/base.pug b/packages/backend/src/server/web/views/base.pug
index 3883b5e5ab..a76c75fe5c 100644
--- a/packages/backend/src/server/web/views/base.pug
+++ b/packages/backend/src/server/web/views/base.pug
@@ -37,7 +37,6 @@ html
 		link(rel='prefetch' href=serverErrorImageUrl)
 		link(rel='prefetch' href=infoImageUrl)
 		link(rel='prefetch' href=notFoundImageUrl)
-		link(rel='modulepreload' href=`/vite/${entry.file}`)
 
 		if !config.frontendManifestExists
 				script(type="module" src="/vite/@vite/client")
@@ -69,7 +68,7 @@ html
 
 		script.
 			var VERSION = "#{version}";
-			var CLIENT_ENTRY = "#{entry.file}";
+			var CLIENT_ENTRY = !{JSON.stringify(entry.file)};
 
 		script(type='application/json' id='misskey_meta' data-generated-at=now)
 			!= metaJson