🐛 Fixed translations not being picked up in newsletters without reboot (#21549)

ref https://ghost.org/changelog/internationalization/

- this fixes an error in which changing the language (or sliding the i18n
toggle) didn't correctly update email-service.

---------

Co-authored-by: Sag <guptazy@gmail.com>

ghost/core/core/server/services/email-service/EmailServiceWrapper.js

@@ -1,5 +1,7 @@
+const debug = require('@tryghost/debug')('i18n');
 const logging = require('@tryghost/logging');
 const url = require('../../api/endpoints/utils/serializers/output/utils/url');
+const events = require('../../lib/common/events');
 
 class EmailServiceWrapper {
     getPostUrl(post) {
@@ -49,8 +51,25 @@ class EmailServiceWrapper {
         const mailgunClient = new MailgunClient({
             config: configService, settings: settingsCache
         });
-        const i18nLanguage = settingsCache.get('locale') || 'en';
+        const i18nLanguage = labs.isSet('i18n') ? settingsCache.get('locale') || 'en' : 'en';
         const i18n = i18nLib(i18nLanguage, 'newsletter');
+        
+        events.on('settings.labs.edited', () => {
+            if (labs.isSet('i18n')) {
+                debug('labs i18n enabled, updating i18n to', settingsCache.get('locale'));
+                i18n.changeLanguage(settingsCache.get('locale'));
+            } else {
+                debug('labs i18n disabled, updating i18n to en');
+                i18n.changeLanguage('en');
+            }
+        });
+    
+        events.on('settings.locale.edited', (model) => {
+            if (labs.isSet('i18n')) {
+                debug('locale changed, updating i18n to', model.get('value'));
+                i18n.changeLanguage(model.get('value'));
+            } 
+        });
 
         const mailgunEmailProvider = new MailgunEmailProvider({
             mailgunClient,

ghost/core/test/e2e-browser/admin/i18n.spec.js

@@ -0,0 +1,46 @@
+const {expect} = require('@playwright/test');
+const test = require('../fixtures/ghost-test');
+const {createPostDraft} = require('../utils');
+
+/**
+ * @param {import('@playwright/test').Page} page
+ */
+
+test.describe('i18n', () => {
+    test.describe('Newsletter', () => {
+        test('changing the site language immediately translates strings in newsletters', async ({sharedPage}) => {
+            await sharedPage.goto('/ghost/#/settings/publication-language');
+            const section = sharedPage.getByTestId('publication-language');
+            await section.getByRole('button', {name: 'Edit'}).click();
+            const input = section.getByPlaceholder('Site language');
+            await input.fill('fr');
+            await section.getByRole('button', {name: 'Save'}).click();
+
+            const labsSection = sharedPage.getByTestId('labs');
+            await labsSection.getByRole('button', {name: 'Open'}).click();
+            let portalLabel = labsSection.getByText('Portal translation');
+            let portalToggle = portalLabel.locator('..').locator('..').locator('..').getByRole('switch');
+            await portalToggle.click();
+
+            const postData = {
+                title: 'Publish and email post',
+                body: 'This is my post body.'
+            };
+
+            await sharedPage.goto('/ghost');
+            await createPostDraft(sharedPage, postData);
+
+            // click the publish-preview button
+            await sharedPage.locator('[data-test-button="publish-preview"]').first().click();
+            // wait for the preview to load
+            await sharedPage.waitForSelector('[data-test-button="email-preview"]');
+            await sharedPage.locator('[data-test-button="email-preview"]').first().click();
+
+            await sharedPage.waitForTimeout(1000);
+
+            const metaText = await sharedPage.frameLocator('iframe.gh-pe-iframe').locator('td.post-meta').first().textContent();
+            expect(metaText).toContain('Par Joe Bloggs');
+            expect(metaText).not.toContain('By Joe Bloggs');
+        });
+    });
+});

ghost/core/test/e2e-browser/admin/publishing.spec.js

@@ -427,7 +427,7 @@ test.describe('Publishing', () => {
             await sharedPage.goto('/ghost');
             await createPostDraft(sharedPage, postData);
             const editorUrl = await sharedPage.url();
-            
+
             // Schedule the post to publish asap (by setting it to 00:00, it will get auto corrected to the minimum time possible - 5 seconds in the future)
             await publishPost(sharedPage, {type: 'send', time: '00:00'});
             await closePublishFlow(sharedPage);