Improve i18n caching (#12030)

* fix indentation

* wip: cache i18n responses

* cache i18n browser script to disk

* typos

* misc fixes

.gitignore

@@ -4,6 +4,7 @@ website/transpiled-babel/
 website/common/transpiled-babel/
 node_modules
 content_cache
+i18n_cache
 apidoc_build
 *.swp
 .idea*

gulp/gulp-build.js

@@ -11,10 +11,16 @@ gulp.task('build:babel:common', () => gulp.src('website/common/script/**/*.js')
 
 gulp.task('build:babel', gulp.parallel('build:babel:server', 'build:babel:common', done => done()));
 
+gulp.task('build:cache', gulp.parallel(
+  'cache:content',
+  'cache:i18n',
+  done => done(),
+));
+
 gulp.task('build:prod', gulp.series(
   'build:babel',
   'apidoc',
-  'content:cache',
+  'build:cache',
   done => done(),
 ));
 

gulp/gulp-cache.js

@@ -2,7 +2,7 @@ import gulp from 'gulp';
 import fs from 'fs';
 
 // TODO parallelize, use gulp file helpers
-gulp.task('content:cache', done => {
+gulp.task('cache:content', done => {
   // Requiring at runtime because these files access `common`
   // code which in production works only if transpiled so after
   // gulp build:babel:common has run
@@ -32,3 +32,32 @@ gulp.task('content:cache', done => {
     done(err);
   }
 });
+
+gulp.task('cache:i18n', done => {
+  // Requiring at runtime because these files access `common`
+  // code which in production works only if transpiled so after
+  // gulp build:babel:common has run
+  const { BROWSER_SCRIPT_CACHE_PATH, geti18nBrowserScript } = require('../website/server/libs/i18n'); // eslint-disable-line global-require
+  const { langCodes } = require('../website/server/libs/i18n'); // eslint-disable-line global-require
+
+  try {
+    // create the cache folder (if it doesn't exist)
+    try {
+      fs.mkdirSync(BROWSER_SCRIPT_CACHE_PATH);
+    } catch (err) {
+      if (err.code !== 'EEXIST') throw err;
+    }
+
+    // create and save the i18n browser script for each language
+    langCodes.forEach(languageCode => {
+      fs.writeFileSync(
+        `${BROWSER_SCRIPT_CACHE_PATH}${languageCode}.js`,
+        geti18nBrowserScript(languageCode),
+        'utf8',
+      );
+    });
+    done();
+  } catch (err) {
+    done(err);
+  }
+});

gulpfile.js

@@ -13,11 +13,11 @@ const gulp = require('gulp');
 
 if (process.env.NODE_ENV === 'production') { // eslint-disable-line no-process-env
   require('./gulp/gulp-apidoc'); // eslint-disable-line global-require
-  require('./gulp/gulp-content'); // eslint-disable-line global-require
+  require('./gulp/gulp-cache'); // eslint-disable-line global-require
   require('./gulp/gulp-build'); // eslint-disable-line global-require
 } else {
   require('./gulp/gulp-apidoc'); // eslint-disable-line global-require
-  require('./gulp/gulp-content'); // eslint-disable-line global-require
+  require('./gulp/gulp-cache'); // eslint-disable-line global-require
   require('./gulp/gulp-build'); // eslint-disable-line global-require
   require('./gulp/gulp-console'); // eslint-disable-line global-require
   require('./gulp/gulp-sprites'); // eslint-disable-line global-require

website/server/controllers/api-v3/i18n.js

@@ -1,26 +1,13 @@
-import _ from 'lodash';
+import nconf from 'nconf';
 import {
-  translations,
-  momentLangs,
-  availableLanguages,
+  BROWSER_SCRIPT_CACHE_PATH,
+  geti18nBrowserScript,
 } from '../../libs/i18n';
 
+const IS_PROD = nconf.get('IS_PROD');
+
 const api = {};
 
-function geti18nBrowserScript (language) {
-  const langCode = language.code;
-
-  return `(function () {
-    if (!window) return;
-    window['habitica-i18n'] = ${JSON.stringify({
-    availableLanguages,
-    language,
-    strings: translations[langCode],
-    momentLang: momentLangs[langCode],
-  })};
-  })()`;
-}
-
 /**
  * @api {get} /api/v3/i18n/browser-script Returns the i18n JS script.
  * @apiDescription Returns the i18n JS script to make
@@ -33,14 +20,16 @@ api.geti18nBrowserScript = {
   method: 'GET',
   url: '/i18n/browser-script',
   async handler (req, res) {
-    const language = _.find(availableLanguages, { code: req.language });
-
+    if (IS_PROD) {
+      res.sendFile(`${BROWSER_SCRIPT_CACHE_PATH}${req.language}.js`);
+    } else {
       res.set({
         'Content-Type': 'application/javascript',
       });
 
-    const jsonResString = geti18nBrowserScript(language);
+      const jsonResString = geti18nBrowserScript(req.language);
       res.status(200).send(jsonResString);
+    }
   },
 };
 

website/server/libs/i18n.js

@@ -4,6 +4,7 @@ import _ from 'lodash';
 import shared from '../../common';
 
 export const localePath = path.join(__dirname, '../../common/locales/');
+export const BROWSER_SCRIPT_CACHE_PATH = path.join(__dirname, '/../../../i18n_cache/');
 
 // Store translations
 export const translations = {};
@@ -115,3 +116,17 @@ export const multipleVersionsLanguages = {
     'pt-br': 'pt_BR',
   },
 };
+
+export function geti18nBrowserScript (languageCode) {
+  const language = _.find(availableLanguages, { code: languageCode });
+
+  return `(function () {
+    if (!window) return;
+    window['habitica-i18n'] = ${JSON.stringify({
+    availableLanguages,
+    language,
+    strings: translations[languageCode],
+    momentLang: momentLangs[languageCode],
+  })};
+  })()`;
+}