add multi language support to banner message

public/config.js

@@ -6,8 +6,11 @@ window.__APP_CONFIG__ = {
   // Base URL of your Dataverse backend
   backendUrl: 'http://localhost:8000',
   // Optional banner shown at the top of the app when set. Basic HTML markup is supported.
-  bannerMessage:
-    "You are using the new Dataverse <strong>Modern version</strong>. This is an early release and some features from the original site are not yet available. Please see the <a href='https://dataverse.harvard.edu/modern/featured-item/harvard/1'>Project Roadmap</a> for details.",
+  // Use a string for one message across all languages, or map language codes to localized messages.
+  bannerMessage: {
+    en: "You are using the new Dataverse <strong>Modern version</strong>. This is an early release and some features from the original site are not yet available. Please see the <a href='https://dataverse.harvard.edu/modern/featured-item/harvard/1'>Project Roadmap</a> for details.",
+    es: "Está utilizando la nueva <strong>versión moderna</strong> de Dataverse. Esta es una versión preliminar y algunas funciones del sitio original aún no están disponibles. Consulte la <a href='https://dataverse.harvard.edu/modern/featured-item/harvard/1'>hoja de ruta del proyecto</a> para más detalles."
+  },
   // OIDC provider settings
   oidc: {
     clientId: 'test',

src/config.ts

@@ -8,9 +8,11 @@ declare global {
 
 let CONFIG: AppConfig | undefined
 
+const BannerMessageSchema = z.union([z.string(), z.record(z.string(), z.string())])
+
 const AppConfigSchema = z.object({
   backendUrl: z.url(),
-  bannerMessage: z.string().optional(),
+  bannerMessage: BannerMessageSchema.optional(),
   oidc: z.object({
     clientId: z.string(),
     authorizationEndpoint: z.url(),

src/sections/layout/Layout.tsx

@@ -1,17 +1,25 @@
 import DOMPurify from 'dompurify'
 import { Outlet } from 'react-router-dom'
 import { Container } from '@iqss/dataverse-design-system'
+import { useTranslation } from 'react-i18next'
 import styles from './Layout.module.scss'
 import { FooterFactory } from './footer/FooterFactory'
 import TopBarProgressIndicator from './topbar-progress-indicator/TopbarProgressIndicator'
 import { HeaderFactory } from './header/HeaderFactory'
 import { HistoryTrackerProvider } from '@/router/HistoryTrackerProvider'
 import { requireAppConfig } from '@/config'
+import type { AppConfig } from '@/config'
 
 export function Layout() {
-  const { bannerMessage } = requireAppConfig()
-  const sanitizedBannerMessage = bannerMessage
-    ? DOMPurify.sanitize(bannerMessage, { USE_PROFILES: { html: true } })
+  const { i18n } = useTranslation()
+  const { bannerMessage, defaultLanguage } = requireAppConfig()
+  const localizedBannerMessage = getLocalizedBannerMessage(
+    bannerMessage,
+    i18n.resolvedLanguage ?? i18n.language,
+    defaultLanguage
+  )
+  const sanitizedBannerMessage = localizedBannerMessage
+    ? DOMPurify.sanitize(localizedBannerMessage, { USE_PROFILES: { html: true } })
     : null
 
   return (
@@ -34,3 +42,29 @@ export function Layout() {
     </HistoryTrackerProvider>
   )
 }
+
+function getLocalizedBannerMessage(
+  bannerMessage: AppConfig['bannerMessage'],
+  selectedLanguage: string | undefined,
+  defaultLanguage: string
+): string | undefined {
+  if (!bannerMessage || typeof bannerMessage === 'string') return bannerMessage
+
+  const normalizedMessages = Object.fromEntries(
+    Object.entries(bannerMessage).map(([language, message]) => [language.toLowerCase(), message])
+  )
+  const selectedLanguageCode = selectedLanguage?.toLowerCase()
+  const defaultLanguageCode = defaultLanguage.toLowerCase()
+  const candidateLanguages = [
+    selectedLanguageCode,
+    selectedLanguageCode?.split('-')[0],
+    defaultLanguageCode,
+    defaultLanguageCode.split('-')[0]
+  ].filter((language): language is string => Boolean(language))
+
+  for (const language of candidateLanguages) {
+    if (normalizedMessages[language]) return normalizedMessages[language]
+  }
+
+  return Object.values(bannerMessage)[0]
+}

tests/component/sections/layout/Layout.spec.tsx

@@ -4,6 +4,7 @@ import { FooterMother } from './footer/FooterMother'
 import { Layout } from '../../../../src/sections/layout/Layout'
 import { applyTestAppConfig } from '../../../support/bootstrapAppConfig'
 import type { AppConfig } from '@/config'
+import i18next from '@/i18n'
 
 describe('Layout', () => {
   const sandbox: SinonSandbox = createSandbox()
@@ -17,6 +18,8 @@ describe('Layout', () => {
     sandbox.restore()
     Cypress.env('bannerMessage', defaultBannerMessageEnv)
     applyTestAppConfig()
+    cy.clearAllLocalStorage()
+    cy.wrap(i18next.changeLanguage('en'))
   })
 
   it('renders the header', () => {
@@ -60,4 +63,41 @@ describe('Layout', () => {
       cy.get('script').should('not.exist')
     })
   })
+
+  it('renders the banner message for the selected header language', () => {
+    Cypress.env('bannerMessage', {
+      en: 'English <strong>banner</strong>',
+      es: 'Banner en español <strong>moderno</strong>'
+    })
+    applyTestAppConfig()
+
+    cy.customMount(<Layout />)
+
+    cy.findByRole('alert').within(() => {
+      cy.findByText('English', { exact: false }).should('exist')
+      cy.findByText('Banner en español', { exact: false }).should('not.exist')
+    })
+
+    cy.findByRole('button', { name: 'Toggle navigation' }).click()
+    cy.get('#language-switcher-dropdown').click()
+    cy.findByText('Español').click()
+
+    cy.findByRole('alert').within(() => {
+      cy.findByText('Banner en español', { exact: false }).should('exist')
+      cy.get('strong').should('contain.text', 'moderno')
+      cy.findByText('English', { exact: false }).should('not.exist')
+    })
+  })
+
+  it('falls back to the default language banner when the selected language is not configured', () => {
+    Cypress.env('bannerMessage', {
+      en: 'Default language banner'
+    })
+    applyTestAppConfig()
+
+    cy.wrap(i18next.changeLanguage('es'))
+    cy.customMount(<Layout />)
+
+    cy.findByRole('alert').should('contain.text', 'Default language banner')
+  })
 })