feat: fetch frontend config in server side rendering

Signed-off-by: Tilman Vatteroth <git@tilmanvatteroth.de>

frontend/src/api/config/index.ts

@@ -1,10 +1,10 @@
 /*
- * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ * SPDX-FileCopyrightText: 2023 The HedgeDoc developers (see AUTHORS file)
  *
  * SPDX-License-Identifier: AGPL-3.0-only
  */
 import { GetApiRequestBuilder } from '../common/api-request-builder/get-api-request-builder'
-import type { Config } from './types'
+import type { FrontendConfig } from './types'
 
 /**
  * Fetches the frontend config from the backend.
@@ -12,7 +12,7 @@ import type { Config } from './types'
  * @return The frontend config.
  * @throws {Error} when the api request wasn't successful.
  */
-export const getConfig = async (): Promise<Config> => {
+export const getConfig = async (baseUrl?: string): Promise<FrontendConfig> => {
-  const response = await new GetApiRequestBuilder<Config>('config').sendRequest()
+  const response = await new GetApiRequestBuilder<FrontendConfig>('config', baseUrl).sendRequest()
   return response.asParsedJsonObject()
 }

frontend/src/api/config/types.ts

@@ -1,10 +1,10 @@
 /*
- * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ * SPDX-FileCopyrightText: 2023 The HedgeDoc developers (see AUTHORS file)
  *
  * SPDX-License-Identifier: AGPL-3.0-only
  */
 
-export interface Config {
+export interface FrontendConfig {
   allowAnonymous: boolean
   allowRegister: boolean
   authProviders: AuthProvider[]

frontend/src/components/application-loader/initializers/fetch-frontend-config.ts

@@ -1,18 +0,0 @@
-/*
- * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
- *
- * SPDX-License-Identifier: AGPL-3.0-only
- */
-import { getConfig } from '../../../api/config'
-import { setConfig } from '../../../redux/config/methods'
-
-/**
- * Get the {@link Config frontend config} and save it in the global application state.
- */
-export const fetchFrontendConfig = async (): Promise<void> => {
-  const config = await getConfig()
-  if (!config) {
-    return Promise.reject(new Error('Config empty!'))
-  }
-  setConfig(config)
-}

frontend/src/components/application-loader/initializers/index.ts

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ * SPDX-FileCopyrightText: 2023 The HedgeDoc developers (see AUTHORS file)
  *
  * SPDX-License-Identifier: AGPL-3.0-only
  */
@@ -7,7 +7,6 @@ import { refreshHistoryState } from '../../../redux/history/methods'
 import { Logger } from '../../../utils/logger'
 import { isDevMode, isTestMode } from '../../../utils/test-modes'
 import { fetchAndSetUser } from '../../login-page/auth/utils'
-import { fetchFrontendConfig } from './fetch-frontend-config'
 import { loadDarkMode } from './load-dark-mode'
 import { setUpI18n } from './setupI18n'
 
@@ -55,10 +54,6 @@ export const createSetUpTaskList = (): InitTask[] => {
       name: 'Load Translations',
       task: setUpI18n
     },
-    {
-      name: 'Load config',
-      task: fetchFrontendConfig
-    },
     {
       name: 'Fetch user information',
       task: fetchUserInformation

frontend/src/components/common/base-url/base-url-context-provider.tsx

@@ -1,10 +1,10 @@
 /*
- * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ * SPDX-FileCopyrightText: 2023 The HedgeDoc developers (see AUTHORS file)
  *
  * SPDX-License-Identifier: AGPL-3.0-only
  */
-import React, { createContext, useState } from 'react'
 import type { PropsWithChildren } from 'react'
+import React, { createContext, useState } from 'react'
 
 export interface BaseUrls {
   renderer: string
@@ -28,9 +28,8 @@ export const BaseUrlContextProvider: React.FC<PropsWithChildren<BaseUrlContextPr
   children
 }) => {
   const [baseUrlState] = useState<undefined | BaseUrls>(() => baseUrls)
-
   return baseUrlState === undefined ? (
-    <div className={'text-white'}>HedgeDoc is not configured correctly! Please check the server log.</div>
+    <span className={'text-white bg-dark'}>HedgeDoc is not configured correctly! Please check the server log.</span>
   ) : (
     <baseUrlContext.Provider value={baseUrlState}>{children}</baseUrlContext.Provider>
   )

frontend/src/components/common/branding/branding.tsx

@@ -1,9 +1,9 @@
 /*
- * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ * SPDX-FileCopyrightText: 2023 The HedgeDoc developers (see AUTHORS file)
  *
  * SPDX-License-Identifier: AGPL-3.0-only
  */
-import { useApplicationState } from '../../../hooks/common/use-application-state'
+import { useFrontendConfig } from '../frontend-config-context/use-frontend-config'
 import { ShowIf } from '../show-if/show-if'
 import styles from './branding.module.scss'
 import React, { useMemo } from 'react'
@@ -21,7 +21,7 @@ export interface BrandingProps {
  * @param delimiter If the delimiter between the HedgeDoc logo and the branding should be shown.
  */
 export const Branding: React.FC<BrandingProps> = ({ inline = false, delimiter = true }) => {
-  const branding = useApplicationState((state) => state.config.branding)
+  const branding = useFrontendConfig().branding
   const showBranding = !!branding.name || !!branding.logo
 
   const brandingDom = useMemo(() => {

frontend/src/components/common/frontend-config-context/context.ts

@@ -0,0 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2023 The HedgeDoc developers (see AUTHORS file)
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+import type { FrontendConfig } from '../../../api/config/types'
+import { createContext } from 'react'
+
+export const frontendConfigContext = createContext<FrontendConfig | undefined>(undefined)

frontend/src/components/common/frontend-config-context/frontend-config-context-provider.tsx

@@ -0,0 +1,45 @@
+/*
+ * SPDX-FileCopyrightText: 2023 The HedgeDoc developers (see AUTHORS file)
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+import { getConfig } from '../../../api/config'
+import type { FrontendConfig } from '../../../api/config/types'
+import { useBaseUrl } from '../../../hooks/common/use-base-url'
+import { Logger } from '../../../utils/logger'
+import { frontendConfigContext } from './context'
+import type { PropsWithChildren } from 'react'
+import React, { useEffect, useState } from 'react'
+
+const logger = new Logger('FrontendConfigContextProvider')
+
+interface FrontendConfigContextProviderProps extends PropsWithChildren {
+  config?: FrontendConfig
+}
+
+/**
+ * Provides the given frontend configuration in a context or renders an error message otherwise.
+ *
+ * @param config the frontend config to provoide
+ * @param children the react elements to show if the config is valid
+ */
+export const FrontendConfigContextProvider: React.FC<FrontendConfigContextProviderProps> = ({ config, children }) => {
+  const [configState, setConfigState] = useState<undefined | FrontendConfig>(() => config)
+
+  const baseUrl = useBaseUrl()
+
+  useEffect(() => {
+    if (config === undefined && configState === undefined) {
+      logger.debug('Fetching Config client side')
+      getConfig(baseUrl)
+        .then((config) => setConfigState(config))
+        .catch((error) => logger.error(error))
+    }
+  }, [baseUrl, config, configState])
+
+  return configState === undefined ? (
+    <span className={'text-white bg-dark'}>No frontend config received! Please check the server log.</span>
+  ) : (
+    <frontendConfigContext.Provider value={configState}>{children}</frontendConfigContext.Provider>
+  )
+}

frontend/src/components/common/frontend-config-context/use-frontend-config.ts

@@ -0,0 +1,18 @@
+/*
+ * SPDX-FileCopyrightText: 2023 The HedgeDoc developers (see AUTHORS file)
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+import type { FrontendConfig } from '../../../api/config/types'
+import { frontendConfigContext } from './context'
+import { Optional } from '@mrdrogdrog/optional'
+import { useContext } from 'react'
+
+/**
+ * Retrieves the current frontend config from the next react context.
+ */
+export const useFrontendConfig = (): FrontendConfig => {
+  return Optional.ofNullable(useContext(frontendConfigContext)).orElseThrow(
+    () => new Error('No frontend config context found. Did you forget to use the provider component?')
+  )
+}

frontend/src/components/common/motd-modal/motd-modal.spec.tsx

@@ -22,7 +22,7 @@ jest.mock('../../../hooks/common/use-base-url')
 
 describe('motd modal', () => {
   beforeAll(async () => {
-    jest.spyOn(UseBaseUrlModule, 'useBaseUrl').mockImplementation(() => 'https://example.org')
+    jest.spyOn(UseBaseUrlModule, 'useBaseUrl').mockImplementation(() => new URL('https://example.org'))
     await mockI18n()
   })
 

frontend/src/components/editor-page/document-bar/share/note-url-field.tsx

@@ -0,0 +1,36 @@
+/*
+ * SPDX-FileCopyrightText: 2023 The HedgeDoc developers (see AUTHORS file)
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+import { useApplicationState } from '../../../../hooks/common/use-application-state'
+import { useBaseUrl } from '../../../../hooks/common/use-base-url'
+import { CopyableField } from '../../../common/copyable/copyable-field/copyable-field'
+import React, { useMemo } from 'react'
+
+export enum LinkType {
+  EDITOR = 'n',
+  SLIDESHOW = 'p',
+  DOCUMENT = 's'
+}
+
+export interface LinkFieldProps {
+  type: LinkType
+}
+
+/**
+ * Renders a specific URL to the current note.
+ * @param type defines the URL type. (editor, read only document, slideshow, etc.)
+ */
+export const NoteUrlField: React.FC<LinkFieldProps> = ({ type }) => {
+  const baseUrl = useBaseUrl()
+  const noteIdentifier = useApplicationState((state) => state.noteDetails.primaryAddress)
+
+  const url = useMemo(() => {
+    const url = new URL(baseUrl)
+    url.pathname += `${type}/${noteIdentifier}`
+    return url.toString()
+  }, [baseUrl, noteIdentifier, type])
+
+  return <CopyableField content={url} shareOriginUrl={url} />
+}

frontend/src/components/editor-page/document-bar/share/share-modal.tsx

@@ -4,11 +4,10 @@
  * SPDX-License-Identifier: AGPL-3.0-only
  */
 import { useApplicationState } from '../../../../hooks/common/use-application-state'
-import { useBaseUrl } from '../../../../hooks/common/use-base-url'
-import { CopyableField } from '../../../common/copyable/copyable-field/copyable-field'
 import type { ModalVisibilityProps } from '../../../common/modals/common-modal'
 import { CommonModal } from '../../../common/modals/common-modal'
 import { ShowIf } from '../../../common/show-if/show-if'
+import { LinkType, NoteUrlField } from './note-url-field'
 import { NoteType } from '@hedgedoc/commons'
 import React from 'react'
 import { Modal } from 'react-bootstrap'
@@ -23,21 +22,19 @@ import { Trans, useTranslation } from 'react-i18next'
 export const ShareModal: React.FC<ModalVisibilityProps> = ({ show, onHide }) => {
   useTranslation()
   const noteFrontmatter = useApplicationState((state) => state.noteDetails.frontmatter)
-  const baseUrl = useBaseUrl()
-  const noteIdentifier = useApplicationState((state) => state.noteDetails.primaryAddress)
 
   return (
     <CommonModal show={show} onHide={onHide} showCloseButton={true} titleI18nKey={'editor.modal.shareLink.title'}>
       <Modal.Body>
         <Trans i18nKey={'editor.modal.shareLink.editorDescription'} />
-        <CopyableField content={`${baseUrl}n/${noteIdentifier}`} shareOriginUrl={`${baseUrl}n/${noteIdentifier}`} />
+        <NoteUrlField type={LinkType.EDITOR} />
         <ShowIf condition={noteFrontmatter.type === NoteType.SLIDE}>
           <Trans i18nKey={'editor.modal.shareLink.slidesDescription'} />
-          <CopyableField content={`${baseUrl}p/${noteIdentifier}`} shareOriginUrl={`${baseUrl}p/${noteIdentifier}`} />
+          <NoteUrlField type={LinkType.SLIDESHOW} />
         </ShowIf>
         <ShowIf condition={noteFrontmatter.type === NoteType.DOCUMENT}>
           <Trans i18nKey={'editor.modal.shareLink.viewOnlyDescription'} />
-          <CopyableField content={`${baseUrl}s/${noteIdentifier}`} shareOriginUrl={`${baseUrl}s/${noteIdentifier}`} />
+          <NoteUrlField type={LinkType.DOCUMENT} />
         </ShowIf>
       </Modal.Body>
     </CommonModal>

frontend/src/components/editor-page/editor-pane/hooks/yjs/use-websocket-url.ts

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ * SPDX-FileCopyrightText: 2023 The HedgeDoc developers (see AUTHORS file)
  *
  * SPDX-License-Identifier: AGPL-3.0-only
  */
@@ -22,7 +22,7 @@ export const useWebsocketUrl = (): URL | undefined => {
       return LOCAL_FALLBACK_URL
     }
     try {
-      const backendBaseUrlParsed = new URL(baseUrl, window.location.toString())
+      const backendBaseUrlParsed = new URL(baseUrl)
       backendBaseUrlParsed.protocol = backendBaseUrlParsed.protocol === 'https:' ? 'wss:' : 'ws:'
       backendBaseUrlParsed.pathname += 'realtime'
       return backendBaseUrlParsed.toString()

frontend/src/components/editor-page/editor-pane/max-length-warning/max-length-warning-modal.tsx

@@ -3,8 +3,8 @@
  *
  * SPDX-License-Identifier: AGPL-3.0-only
  */
-import { useApplicationState } from '../../../../hooks/common/use-application-state'
 import { cypressId } from '../../../../utils/cypress-attribute'
+import { useFrontendConfig } from '../../../common/frontend-config-context/use-frontend-config'
 import type { ModalVisibilityProps } from '../../../common/modals/common-modal'
 import { CommonModal } from '../../../common/modals/common-modal'
 import React from 'react'
@@ -19,7 +19,7 @@ import { Trans, useTranslation } from 'react-i18next'
  */
 export const MaxLengthWarningModal: React.FC<ModalVisibilityProps> = ({ show, onHide }) => {
   useTranslation()
-  const maxDocumentLength = useApplicationState((state) => state.config.maxDocumentLength)
+  const maxDocumentLength = useFrontendConfig().maxDocumentLength
 
   return (
     <CommonModal

frontend/src/components/editor-page/editor-pane/max-length-warning/max-length-warning.tsx

@@ -1,11 +1,11 @@
 /*
- * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ * SPDX-FileCopyrightText: 2023 The HedgeDoc developers (see AUTHORS file)
  *
  * SPDX-License-Identifier: AGPL-3.0-only
  */
-import { useApplicationState } from '../../../../hooks/common/use-application-state'
 import { useBooleanState } from '../../../../hooks/common/use-boolean-state'
 import { useNoteMarkdownContent } from '../../../../hooks/common/use-note-markdown-content'
+import { useFrontendConfig } from '../../../common/frontend-config-context/use-frontend-config'
 import { MaxLengthWarningModal } from './max-length-warning-modal'
 import React, { useEffect, useRef } from 'react'
 
@@ -15,7 +15,7 @@ import React, { useEffect, useRef } from 'react'
 export const MaxLengthWarning: React.FC = () => {
   const [modalVisibility, showModal, closeModal] = useBooleanState()
   const maxLengthWarningAlreadyShown = useRef(false)
-  const maxDocumentLength = useApplicationState((state) => state.config.maxDocumentLength)
+  const maxDocumentLength = useFrontendConfig().maxDocumentLength
   const markdownContent = useNoteMarkdownContent()
 
   useEffect(() => {

frontend/src/components/editor-page/editor-pane/status-bar/remaining-characters-info.tsx

@@ -1,10 +1,11 @@
 /*
- * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ * SPDX-FileCopyrightText: 2023 The HedgeDoc developers (see AUTHORS file)
  *
  * SPDX-License-Identifier: AGPL-3.0-only
  */
 import { useApplicationState } from '../../../../hooks/common/use-application-state'
 import { cypressId } from '../../../../utils/cypress-attribute'
+import { useFrontendConfig } from '../../../common/frontend-config-context/use-frontend-config'
 import React, { useMemo } from 'react'
 import { Trans, useTranslation } from 'react-i18next'
 
@@ -14,7 +15,7 @@ import { Trans, useTranslation } from 'react-i18next'
 export const RemainingCharactersInfo: React.FC = () => {
   const { t } = useTranslation()
 
-  const maxDocumentLength = useApplicationState((state) => state.config.maxDocumentLength)
+  const maxDocumentLength = useFrontendConfig().maxDocumentLength
   const contentLength = useApplicationState((state) => state.noteDetails.markdownContent.plain.length)
   const remainingCharacters = useMemo(() => maxDocumentLength - contentLength, [contentLength, maxDocumentLength])
 

frontend/src/components/landing-layout/footer/powered-by-links.tsx

@@ -1,15 +1,15 @@
 /*
- * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ * SPDX-FileCopyrightText: 2023 The HedgeDoc developers (see AUTHORS file)
  *
  * SPDX-License-Identifier: AGPL-3.0-only
  */
-import { useApplicationState } from '../../../hooks/common/use-application-state'
 import links from '../../../links.json'
+import { useFrontendConfig } from '../../common/frontend-config-context/use-frontend-config'
 import { ExternalLink } from '../../common/links/external-link'
 import { TranslatedExternalLink } from '../../common/links/translated-external-link'
 import { TranslatedInternalLink } from '../../common/links/translated-internal-link'
 import { VersionInfoLink } from './version-info/version-info-link'
-import React, { Fragment } from 'react'
+import React, { Fragment, useMemo } from 'react'
 import { Trans, useTranslation } from 'react-i18next'
 
 /**
@@ -18,8 +18,11 @@ import { Trans, useTranslation } from 'react-i18next'
 export const PoweredByLinks: React.FC = () => {
   useTranslation()
 
-  const specialUrls: [string, string][] = useApplicationState((state) =>
+  const rawSpecialUrls = useFrontendConfig().specialUrls
-    Object.entries(state.config.specialUrls).map(([i18nkey, url]) => [i18nkey, String(url)])
+
+  const specialUrls = useMemo(
+    () => Object.entries(rawSpecialUrls).map(([i18nkey, url]) => [i18nkey, String(url)]),
+    [rawSpecialUrls]
   )
 
   return (

frontend/src/components/landing-layout/footer/version-info/version-info-modal.tsx

@@ -4,10 +4,10 @@
  * SPDX-License-Identifier: AGPL-3.0-only
  */
 import type { BackendVersion } from '../../../../api/config/types'
-import { useApplicationState } from '../../../../hooks/common/use-application-state'
 import links from '../../../../links.json'
 import { cypressId } from '../../../../utils/cypress-attribute'
 import { CopyableField } from '../../../common/copyable/copyable-field/copyable-field'
+import { useFrontendConfig } from '../../../common/frontend-config-context/use-frontend-config'
 import { TranslatedExternalLink } from '../../../common/links/translated-external-link'
 import type { CommonModalProps } from '../../../common/modals/common-modal'
 import { CommonModal } from '../../../common/modals/common-modal'
@@ -22,7 +22,7 @@ import { Modal } from 'react-bootstrap'
  * @param show If the modal should be shown.
  */
 export const VersionInfoModal: React.FC<CommonModalProps> = ({ onHide, show }) => {
-  const serverVersion: BackendVersion = useApplicationState((state) => state.config.version)
+  const serverVersion: BackendVersion = useFrontendConfig().version
   const backendVersion = useMemo(() => {
     const version = `${serverVersion.major}.${serverVersion.minor}.${serverVersion.patch}`
 

frontend/src/components/landing-layout/navigation/sign-in-button.tsx

@@ -1,10 +1,10 @@
 /*
- * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ * SPDX-FileCopyrightText: 2023 The HedgeDoc developers (see AUTHORS file)
  *
  * SPDX-License-Identifier: AGPL-3.0-only
  */
-import { useApplicationState } from '../../../hooks/common/use-application-state'
 import { cypressId } from '../../../utils/cypress-attribute'
+import { useFrontendConfig } from '../../common/frontend-config-context/use-frontend-config'
 import { ShowIf } from '../../common/show-if/show-if'
 import { filterOneClickProviders } from '../../login-page/auth/utils'
 import { getOneClickProviderMetadata } from '../../login-page/auth/utils/get-one-click-provider-metadata'
@@ -25,7 +25,7 @@ export type SignInButtonProps = Omit<ButtonProps, 'href'>
  */
 export const SignInButton: React.FC<SignInButtonProps> = ({ variant, ...props }) => {
   const { t } = useTranslation()
-  const authProviders = useApplicationState((state) => state.config.authProviders)
+  const authProviders = useFrontendConfig().authProviders
 
   const loginLink = useMemo(() => {
     const oneClickProviders = authProviders.filter(filterOneClickProviders)

frontend/src/components/login-page/auth/via-local.tsx

@@ -1,12 +1,12 @@
 /*
- * SPDX-FileCopyrightText: 2021 The HedgeDoc developers (see AUTHORS file)
+ * SPDX-FileCopyrightText: 2023 The HedgeDoc developers (see AUTHORS file)
  *
  * SPDX-License-Identifier: AGPL-3.0-only
  */
 import { doLocalLogin } from '../../../api/auth/local'
 import { ErrorToI18nKeyMapper } from '../../../api/common/error-to-i18n-key-mapper'
-import { useApplicationState } from '../../../hooks/common/use-application-state'
 import { useOnInputChange } from '../../../hooks/common/use-on-input-change'
+import { useFrontendConfig } from '../../common/frontend-config-context/use-frontend-config'
 import { ShowIf } from '../../common/show-if/show-if'
 import { PasswordField } from './fields/password-field'
 import { UsernameField } from './fields/username-field'
@@ -25,7 +25,7 @@ export const ViaLocal: React.FC = () => {
   const [username, setUsername] = useState('')
   const [password, setPassword] = useState('')
   const [error, setError] = useState<string>()
-  const allowRegister = useApplicationState((state) => state.config.allowRegister)
+  const allowRegister = useFrontendConfig().allowRegister
 
   const onLoginSubmit = useCallback(
     (event: FormEvent) => {

frontend/src/components/markdown-renderer/extensions/image/proxy-image-frame.tsx

@@ -1,11 +1,11 @@
 /*
- * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ * SPDX-FileCopyrightText: 2023 The HedgeDoc developers (see AUTHORS file)
  *
  * SPDX-License-Identifier: AGPL-3.0-only
  */
 import { getProxiedUrl } from '../../../../api/media'
-import { useApplicationState } from '../../../../hooks/common/use-application-state'
 import { Logger } from '../../../../utils/logger'
+import { useFrontendConfig } from '../../../common/frontend-config-context/use-frontend-config'
 import React, { useEffect, useState } from 'react'
 
 const log = new Logger('ProxyImageFrame')
@@ -20,7 +20,7 @@ const log = new Logger('ProxyImageFrame')
  */
 export const ProxyImageFrame: React.FC<React.ImgHTMLAttributes<HTMLImageElement>> = ({ src, title, alt, ...props }) => {
   const [imageUrl, setImageUrl] = useState('')
-  const imageProxyEnabled = useApplicationState((state) => state.config.useImageProxy)
+  const imageProxyEnabled = useFrontendConfig().useImageProxy
 
   useEffect(() => {
     if (!imageProxyEnabled || !src) {

frontend/src/components/markdown-renderer/extensions/table-of-contents/table-of-contents-app-extension.ts

@@ -3,18 +3,18 @@
  *
  * SPDX-License-Identifier: AGPL-3.0-only
  */
+import type { MarkdownRendererExtensionOptions } from '../../../../extensions/base/app-extension'
 import { AppExtension } from '../../../../extensions/base/app-extension'
 import type { CheatsheetExtension } from '../../../editor-page/cheatsheet/cheatsheet-extension'
 import { basicCompletion } from '../../../editor-page/editor-pane/autocompletions/basic-completion'
 import type { MarkdownRendererExtension } from '../base/markdown-renderer-extension'
 import { TableOfContentsMarkdownExtension } from './table-of-contents-markdown-extension'
 import type { CompletionSource } from '@codemirror/autocomplete'
-import type EventEmitter2 from 'eventemitter2'
 import { t } from 'i18next'
 
 export class TableOfContentsAppExtension extends AppExtension {
-  buildMarkdownRendererExtensions(eventEmitter?: EventEmitter2): MarkdownRendererExtension[] {
+  buildMarkdownRendererExtensions(options: MarkdownRendererExtensionOptions): MarkdownRendererExtension[] {
-    return [new TableOfContentsMarkdownExtension(eventEmitter)]
+    return [new TableOfContentsMarkdownExtension(options.eventEmitter)]
   }
 
   buildCheatsheetExtensions(): CheatsheetExtension[] {

frontend/src/components/markdown-renderer/hooks/use-markdown-extensions.ts

@@ -4,6 +4,7 @@
  * SPDX-License-Identifier: AGPL-3.0-only
  */
 import { optionalAppExtensions } from '../../../extensions/extra-integrations/optional-app-extensions'
+import { useFrontendConfig } from '../../common/frontend-config-context/use-frontend-config'
 import type { MarkdownRendererExtension } from '../extensions/base/markdown-renderer-extension'
 import { DebuggerMarkdownExtension } from '../extensions/debugger-markdown-extension'
 import { ProxyImageMarkdownExtension } from '../extensions/image/proxy-image-markdown-extension'
@@ -25,9 +26,15 @@ export const useMarkdownExtensions = (
   additionalExtensions: MarkdownRendererExtension[]
 ): MarkdownRendererExtension[] => {
   const extensionEventEmitter = useExtensionEventEmitter()
+  const frontendConfig = useFrontendConfig()
   return useMemo(() => {
     return [
-      ...optionalAppExtensions.flatMap((extension) => extension.buildMarkdownRendererExtensions(extensionEventEmitter)),
+      ...optionalAppExtensions.flatMap((extension) =>
+        extension.buildMarkdownRendererExtensions({
+          frontendConfig: frontendConfig,
+          eventEmitter: extensionEventEmitter
+        })
+      ),
       ...additionalExtensions,
       new UploadIndicatingImageFrameMarkdownExtension(),
       new LinkAdjustmentMarkdownExtension(baseUrl),
@@ -35,5 +42,5 @@ export const useMarkdownExtensions = (
       new DebuggerMarkdownExtension(),
       new ProxyImageMarkdownExtension()
     ]
-  }, [additionalExtensions, baseUrl, extensionEventEmitter])
+  }, [additionalExtensions, baseUrl, extensionEventEmitter, frontendConfig])
 }

frontend/src/components/register-page/register-infos.tsx

@@ -3,7 +3,7 @@
  *
  * SPDX-License-Identifier: AGPL-3.0-only
  */
-import { useApplicationState } from '../../hooks/common/use-application-state'
+import { useFrontendConfig } from '../common/frontend-config-context/use-frontend-config'
 import { TranslatedExternalLink } from '../common/links/translated-external-link'
 import { ShowIf } from '../common/show-if/show-if'
 import React from 'react'
@@ -14,7 +14,7 @@ import { Trans, useTranslation } from 'react-i18next'
  */
 export const RegisterInfos: React.FC = () => {
   useTranslation()
-  const specialUrls = useApplicationState((state) => state.config.specialUrls)
+  const specialUrls = useFrontendConfig().specialUrls
 
   return (
     <ShowIf condition={!!specialUrls.termsOfUse || !!specialUrls.privacy}>

frontend/src/extensions/base/app-extension.ts

@@ -1,8 +1,9 @@
 /*
- * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ * SPDX-FileCopyrightText: 2023 The HedgeDoc developers (see AUTHORS file)
  *
  * SPDX-License-Identifier: AGPL-3.0-only
  */
+import type { FrontendConfig } from '../../api/config/types'
 import type { CheatsheetExtension } from '../../components/editor-page/cheatsheet/cheatsheet-extension'
 import type { Linter } from '../../components/editor-page/editor-pane/linter/linter'
 import type { MarkdownRendererExtension } from '../../components/markdown-renderer/extensions/base/markdown-renderer-extension'
@@ -11,9 +12,14 @@ import type { EventEmitter2 } from 'eventemitter2'
 import type React from 'react'
 import { Fragment } from 'react'
 
+export interface MarkdownRendererExtensionOptions {
+  frontendConfig: FrontendConfig
+  eventEmitter?: EventEmitter2
+}
+
 export abstract class AppExtension {
   // eslint-disable-next-line @typescript-eslint/no-unused-vars
-  public buildMarkdownRendererExtensions(eventEmitter?: EventEmitter2): MarkdownRendererExtension[] {
+  public buildMarkdownRendererExtensions(options: MarkdownRendererExtensionOptions): MarkdownRendererExtension[] {
     return []
   }
 

frontend/src/extensions/extra-integrations/plantuml/plantuml-app-extension.ts

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ * SPDX-FileCopyrightText: 2023 The HedgeDoc developers (see AUTHORS file)
  *
  * SPDX-License-Identifier: AGPL-3.0-only
  */
@@ -9,6 +9,7 @@ import {
   codeFenceRegex
 } from '../../../components/editor-page/editor-pane/autocompletions/basic-completion'
 import type { MarkdownRendererExtension } from '../../../components/markdown-renderer/extensions/base/markdown-renderer-extension'
+import type { MarkdownRendererExtensionOptions } from '../../base/app-extension'
 import { AppExtension } from '../../base/app-extension'
 import { PlantumlMarkdownExtension } from './plantuml-markdown-extension'
 import type { CompletionSource } from '@codemirror/autocomplete'
@@ -19,8 +20,8 @@ import type { CompletionSource } from '@codemirror/autocomplete'
  * @see https://plantuml.com
  */
 export class PlantumlAppExtension extends AppExtension {
-  buildMarkdownRendererExtensions(): MarkdownRendererExtension[] {
+  buildMarkdownRendererExtensions(options: MarkdownRendererExtensionOptions): MarkdownRendererExtension[] {
-    return [new PlantumlMarkdownExtension()]
+    return [new PlantumlMarkdownExtension(options.frontendConfig.plantumlServer)]
   }
 
   buildCheatsheetExtensions(): CheatsheetExtension[] {

frontend/src/extensions/extra-integrations/plantuml/plantuml-markdown-extension.spec.tsx

@@ -5,30 +5,17 @@
  */
 import { mockI18n } from '../../../components/markdown-renderer/test-utils/mock-i18n'
 import { TestMarkdownRenderer } from '../../../components/markdown-renderer/test-utils/test-markdown-renderer'
-import * as reduxModule from '../../../redux'
-import type { ApplicationState } from '../../../redux/application-state'
 import { PlantumlMarkdownExtension } from './plantuml-markdown-extension'
 import { render } from '@testing-library/react'
 import React from 'react'
-import { Mock } from 'ts-mockery'
-
-jest.mock('../../../redux')
 
 describe('PlantUML markdown extensions', () => {
   beforeAll(() => mockI18n())
 
   it('renders a plantuml codeblock', () => {
-    jest.spyOn(reduxModule, 'getGlobalState').mockReturnValue(
-      Mock.of<ApplicationState>({
-        config: {
-          plantumlServer: 'https://example.org'
-        }
-      })
-    )
-
     const view = render(
       <TestMarkdownRenderer
-        extensions={[new PlantumlMarkdownExtension()]}
+        extensions={[new PlantumlMarkdownExtension('https://example.org')]}
         content={'```plantuml\nclass Example\n```'}
       />
     )
@@ -36,17 +23,9 @@ describe('PlantUML markdown extensions', () => {
   })
 
   it('renders an error if no server is defined', () => {
-    jest.spyOn(reduxModule, 'getGlobalState').mockReturnValue(
-      Mock.of<ApplicationState>({
-        config: {
-          plantumlServer: undefined
-        }
-      })
-    )
-
     const view = render(
       <TestMarkdownRenderer
-        extensions={[new PlantumlMarkdownExtension()]}
+        extensions={[new PlantumlMarkdownExtension(undefined)]}
         content={'```plantuml\nclass Example\n```'}
       />
     )

frontend/src/extensions/extra-integrations/plantuml/plantuml-markdown-extension.ts

@@ -1,11 +1,10 @@
 /*
- * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ * SPDX-FileCopyrightText: 2023 The HedgeDoc developers (see AUTHORS file)
  *
  * SPDX-License-Identifier: AGPL-3.0-only
  */
 import { MarkdownRendererExtension } from '../../../components/markdown-renderer/extensions/base/markdown-renderer-extension'
 import type { ComponentReplacer } from '../../../components/markdown-renderer/replace-components/component-replacer'
-import { getGlobalState } from '../../../redux'
 import { PlantumlNotConfiguredComponentReplacer } from './plantuml-not-configured-component-replacer'
 import { Optional } from '@mrdrogdrog/optional'
 import type MarkdownIt from 'markdown-it'
@@ -20,6 +19,10 @@ import type Token from 'markdown-it/lib/token'
  * @see https://plantuml.com
  */
 export class PlantumlMarkdownExtension extends MarkdownRendererExtension {
+  constructor(private plantumlServerUrl: string | undefined) {
+    super()
+  }
+
   private plantumlError(markdownIt: MarkdownIt): void {
     const defaultRenderer: Renderer.RenderRule = markdownIt.renderer.rules.fence || (() => '')
     markdownIt.renderer.rules.fence = (tokens: Token[], idx: number, options: Options, env, slf: Renderer) => {
@@ -30,7 +33,7 @@ export class PlantumlMarkdownExtension extends MarkdownRendererExtension {
   }
 
   public configureMarkdownIt(markdownIt: MarkdownIt): void {
-    Optional.ofNullable(getGlobalState().config.plantumlServer)
+    Optional.ofNullable(this.plantumlServerUrl)
       .map((plantumlServer) =>
         plantuml(markdownIt, {
           openMarker: '```plantuml',

frontend/src/extensions/extra-integrations/task-list/task-list-checkbox-app-extension.ts

@@ -1,14 +1,14 @@
 /*
- * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ * SPDX-FileCopyrightText: 2023 The HedgeDoc developers (see AUTHORS file)
  *
  * SPDX-License-Identifier: AGPL-3.0-only
  */
 import type { CheatsheetExtension } from '../../../components/editor-page/cheatsheet/cheatsheet-extension'
+import type { MarkdownRendererExtensionOptions } from '../../base/app-extension'
 import { AppExtension } from '../../base/app-extension'
 import { SetCheckboxInCheatsheet } from './set-checkbox-in-cheatsheet'
 import { SetCheckboxInEditor } from './set-checkbox-in-editor'
 import { TaskListMarkdownExtension } from './task-list-markdown-extension'
-import type { EventEmitter2 } from 'eventemitter2'
 import type React from 'react'
 
 /**
@@ -17,8 +17,8 @@ import type React from 'react'
 export class TaskListCheckboxAppExtension extends AppExtension {
   public static readonly EVENT_NAME = 'TaskListCheckbox'
 
-  buildMarkdownRendererExtensions(eventEmitter: EventEmitter2): TaskListMarkdownExtension[] {
+  buildMarkdownRendererExtensions(options: MarkdownRendererExtensionOptions): TaskListMarkdownExtension[] {
-    return [new TaskListMarkdownExtension(eventEmitter)]
+    return [new TaskListMarkdownExtension(options.eventEmitter)]
   }
 
   buildEditorExtensionComponent(): React.FC {

frontend/src/hooks/common/use-app-title.ts

@@ -1,9 +1,9 @@
 /*
- * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ * SPDX-FileCopyrightText: 2023 The HedgeDoc developers (see AUTHORS file)
  *
  * SPDX-License-Identifier: AGPL-3.0-only
  */
-import { useApplicationState } from './use-application-state'
+import { useFrontendConfig } from '../../components/common/frontend-config-context/use-frontend-config'
 import { useMemo } from 'react'
 
 /**
@@ -12,7 +12,7 @@ import { useMemo } from 'react'
  * @return The app title with branding.
  */
 export const useAppTitle = (): string => {
-  const brandingName = useApplicationState((state) => state.config.branding.name)
+  const brandingName = useFrontendConfig().branding.name
 
   return useMemo(() => {
     return 'HedgeDoc' + (brandingName ? ` @ ${brandingName}` : '')

frontend/src/hooks/common/use-trimmed-note-markdown-content-without-frontmatter.ts

@@ -1,8 +1,9 @@
 /*
- * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ * SPDX-FileCopyrightText: 2023 The HedgeDoc developers (see AUTHORS file)
  *
  * SPDX-License-Identifier: AGPL-3.0-only
  */
+import { useFrontendConfig } from '../../components/common/frontend-config-context/use-frontend-config'
 import { useApplicationState } from './use-application-state'
 import { useMemo } from 'react'
 
@@ -12,7 +13,7 @@ import { useMemo } from 'react'
  * @return The array of markdown content lines
  */
 export const useTrimmedNoteMarkdownContentWithoutFrontmatter = (): string[] => {
-  const maxLength = useApplicationState((state) => state.config.maxDocumentLength)
+  const maxLength = useFrontendConfig().maxDocumentLength
   const markdownContent = useApplicationState((state) => ({
     lines: state.noteDetails.markdownContent.lines,
     content: state.noteDetails.markdownContent.plain

frontend/src/pages/_app.tsx

@@ -5,9 +5,11 @@
  */
 import '../../global-styles/dark.scss'
 import '../../global-styles/index.scss'
+import type { FrontendConfig } from '../api/config/types'
 import { ApplicationLoader } from '../components/application-loader/application-loader'
-import { BaseUrlContextProvider } from '../components/common/base-url/base-url-context-provider'
 import type { BaseUrls } from '../components/common/base-url/base-url-context-provider'
+import { BaseUrlContextProvider } from '../components/common/base-url/base-url-context-provider'
+import { FrontendConfigContextProvider } from '../components/common/frontend-config-context/frontend-config-context-provider'
 import { ErrorBoundary } from '../components/error-boundary/error-boundary'
 import { BaseHead } from '../components/layout/base-head'
 import { UiNotificationBoundary } from '../components/notifications/ui-notification-boundary'
@@ -16,6 +18,8 @@ import { BaseUrlFromEnvExtractor } from '../utils/base-url-from-env-extractor'
 import { configureLuxon } from '../utils/configure-luxon'
 import { determineCurrentOrigin } from '../utils/determine-current-origin'
 import { ExpectedOriginBoundary } from '../utils/expected-origin-boundary'
+import { FrontendConfigFetcher } from '../utils/frontend-config-fetcher'
+import { isTestMode } from '../utils/test-modes'
 import type { AppContext, AppInitialProps, AppProps } from 'next/app'
 import React from 'react'
 
@@ -23,6 +27,7 @@ configureLuxon()
 
 interface AppPageProps {
   baseUrls: BaseUrls | undefined
+  frontendConfig: FrontendConfig | undefined
   currentOrigin: string | undefined
 }
 
@@ -33,6 +38,7 @@ interface AppPageProps {
 function HedgeDocApp({ Component, pageProps }: AppProps<AppPageProps>) {
   return (
     <BaseUrlContextProvider baseUrls={pageProps.baseUrls}>
+      <FrontendConfigContextProvider config={pageProps.frontendConfig}>
         <ExpectedOriginBoundary currentOrigin={pageProps.currentOrigin}>
           <StoreProvider>
             <BaseHead />
@@ -45,19 +51,23 @@ function HedgeDocApp({ Component, pageProps }: AppProps<AppPageProps>) {
             </ApplicationLoader>
           </StoreProvider>
         </ExpectedOriginBoundary>
+      </FrontendConfigContextProvider>
     </BaseUrlContextProvider>
   )
 }
 
 const baseUrlFromEnvExtractor = new BaseUrlFromEnvExtractor()
+const frontendConfigFetcher = new FrontendConfigFetcher()
 
-HedgeDocApp.getInitialProps = ({ ctx }: AppContext): AppInitialProps<AppPageProps> => {
+HedgeDocApp.getInitialProps = async ({ ctx }: AppContext): Promise<AppInitialProps<AppPageProps>> => {
   const baseUrls = baseUrlFromEnvExtractor.extractBaseUrls().orElse(undefined)
+  const frontendConfig = isTestMode ? undefined : await frontendConfigFetcher.fetch(baseUrls) //some tests mock the frontend config. Therefore it needs to be fetched in the browser.
   const currentOrigin = determineCurrentOrigin(ctx)
 
   return {
     pageProps: {
       baseUrls,
+      frontendConfig,
       currentOrigin
     }
   }

frontend/src/pages/api/private/config.ts

@@ -1,15 +1,15 @@
 /*
- * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ * SPDX-FileCopyrightText: 2023 The HedgeDoc developers (see AUTHORS file)
  *
  * SPDX-License-Identifier: AGPL-3.0-only
  */
-import type { Config } from '../../../api/config/types'
+import type { FrontendConfig } from '../../../api/config/types'
 import { AuthProviderType } from '../../../api/config/types'
 import { HttpMethod, respondToMatchingRequest } from '../../../handler-utils/respond-to-matching-request'
 import type { NextApiRequest, NextApiResponse } from 'next'
 
 const handler = (req: NextApiRequest, res: NextApiResponse) => {
-  respondToMatchingRequest<Config>(HttpMethod.GET, req, res, {
+  respondToMatchingRequest<FrontendConfig>(HttpMethod.GET, req, res, {
     allowAnonymous: true,
     allowRegister: true,
     authProviders: [

frontend/src/pages/login.tsx

@@ -1,10 +1,11 @@
 /*
- SPDX-FileCopyrightText: 2021 The HedgeDoc developers (see AUTHORS file)
+ * SPDX-FileCopyrightText: 2023 The HedgeDoc developers (see AUTHORS file)
-
+ *
- SPDX-License-Identifier: AGPL-3.0-only
+ * SPDX-License-Identifier: AGPL-3.0-only
  */
 import type { AuthProviderWithCustomName } from '../api/config/types'
 import { AuthProviderType } from '../api/config/types'
+import { useFrontendConfig } from '../components/common/frontend-config-context/use-frontend-config'
 import { RedirectBack } from '../components/common/redirect-back'
 import { ShowIf } from '../components/common/show-if/show-if'
 import { LandingLayout } from '../components/landing-layout/landing-layout'
@@ -23,7 +24,7 @@ import { Trans, useTranslation } from 'react-i18next'
  */
 export const LoginPage: React.FC = () => {
   useTranslation()
-  const authProviders = useApplicationState((state) => state.config.authProviders)
+  const authProviders = useFrontendConfig().authProviders
   const userLoggedIn = useApplicationState((state) => !!state.user)
 
   const ldapProviders = useMemo(() => {

frontend/src/pages/register.tsx

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ * SPDX-FileCopyrightText: 2023 The HedgeDoc developers (see AUTHORS file)
  *
  * SPDX-License-Identifier: AGPL-3.0-only
  */
@@ -9,6 +9,7 @@ import { DisplayNameField } from '../components/common/fields/display-name-field
 import { NewPasswordField } from '../components/common/fields/new-password-field'
 import { PasswordAgainField } from '../components/common/fields/password-again-field'
 import { UsernameField } from '../components/common/fields/username-field'
+import { useFrontendConfig } from '../components/common/frontend-config-context/use-frontend-config'
 import { Redirect } from '../components/common/redirect'
 import { LandingLayout } from '../components/landing-layout/landing-layout'
 import { fetchAndSetUser } from '../components/login-page/auth/utils'
@@ -30,7 +31,7 @@ import { Trans, useTranslation } from 'react-i18next'
 export const RegisterPage: NextPage = () => {
   useTranslation()
   const router = useRouter()
-  const allowRegister = useApplicationState((state) => state.config.allowRegister)
+  const allowRegister = useFrontendConfig().allowRegister
   const userExists = useApplicationState((state) => !!state.user)
 
   const [username, setUsername] = useState('')

frontend/src/redux/application-state.d.ts

@@ -3,7 +3,6 @@
  *
  * SPDX-License-Identifier: AGPL-3.0-only
  */
-import type { Config } from '../api/config/types'
 import type { HistoryEntryWithOrigin } from '../api/history/types'
 import type { DarkModeConfig } from './dark-mode/types'
 import type { EditorConfig } from './editor/types'
@@ -14,7 +13,6 @@ import type { OptionalUserState } from './user/types'
 
 export interface ApplicationState {
   user: OptionalUserState
-  config: Config
   history: HistoryEntryWithOrigin[]
   editorConfig: EditorConfig
   darkMode: DarkModeConfig

frontend/src/redux/config/methods.ts

@@ -1,16 +0,0 @@
-/*
- * SPDX-FileCopyrightText: 2021 The HedgeDoc developers (see AUTHORS file)
- *
- * SPDX-License-Identifier: AGPL-3.0-only
- */
-import { store } from '..'
-import type { Config } from '../../api/config/types'
-import type { SetConfigAction } from './types'
-import { ConfigActionType } from './types'
-
-export const setConfig = (state: Config): void => {
-  store.dispatch({
-    type: ConfigActionType.SET_CONFIG,
-    state: state
-  } as SetConfigAction)
-}

frontend/src/redux/config/reducers.ts

@@ -1,41 +0,0 @@
-/*
- * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
- *
- * SPDX-License-Identifier: AGPL-3.0-only
- */
-import type { Config } from '../../api/config/types'
-import type { ConfigActions } from './types'
-import { ConfigActionType } from './types'
-import type { Reducer } from 'redux'
-
-export const initialState: Config = {
-  allowAnonymous: true,
-  allowRegister: true,
-  authProviders: [],
-  branding: {
-    name: '',
-    logo: ''
-  },
-  useImageProxy: false,
-  specialUrls: {
-    privacy: undefined,
-    termsOfUse: undefined,
-    imprint: undefined
-  },
-  version: {
-    major: 0,
-    minor: 0,
-    patch: 0
-  },
-  plantumlServer: undefined,
-  maxDocumentLength: 0
-}
-
-export const ConfigReducer: Reducer<Config, ConfigActions> = (state: Config = initialState, action: ConfigActions) => {
-  switch (action.type) {
-    case ConfigActionType.SET_CONFIG:
-      return action.state
-    default:
-      return state
-  }
-}

frontend/src/redux/config/types.ts

@@ -1,18 +0,0 @@
-/*
- * SPDX-FileCopyrightText: 2021 The HedgeDoc developers (see AUTHORS file)
- *
- * SPDX-License-Identifier: AGPL-3.0-only
- */
-import type { Config } from '../../api/config/types'
-import type { Action } from 'redux'
-
-export enum ConfigActionType {
-  SET_CONFIG = 'config/set'
-}
-
-export type ConfigActions = SetConfigAction
-
-export interface SetConfigAction extends Action<ConfigActionType> {
-  type: ConfigActionType.SET_CONFIG
-  state: Config
-}

frontend/src/redux/reducers.ts

@@ -1,10 +1,9 @@
 /*
- * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ * SPDX-FileCopyrightText: 2023 The HedgeDoc developers (see AUTHORS file)
  *
  * SPDX-License-Identifier: AGPL-3.0-only
  */
 import type { ApplicationState } from './application-state'
-import { ConfigReducer } from './config/reducers'
 import { DarkModeConfigReducer } from './dark-mode/reducers'
 import { EditorConfigReducer } from './editor/reducers'
 import { HistoryReducer } from './history/reducers'
@@ -17,7 +16,6 @@ import { combineReducers } from 'redux'
 
 export const allReducers: Reducer<ApplicationState> = combineReducers<ApplicationState>({
   user: UserReducer,
-  config: ConfigReducer,
   history: HistoryReducer,
   editorConfig: EditorConfigReducer,
   darkMode: DarkModeConfigReducer,

frontend/src/utils/frontend-config-fetcher.ts

@@ -0,0 +1,35 @@
+/*
+ * SPDX-FileCopyrightText: 2023 The HedgeDoc developers (see AUTHORS file)
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+import { getConfig } from '../api/config'
+import type { FrontendConfig } from '../api/config/types'
+import type { BaseUrls } from '../components/common/base-url/base-url-context-provider'
+import { Logger } from './logger'
+
+/**
+ * Fetches and caches the {@link FrontendConfig frontend config} from the backend.
+ */
+export class FrontendConfigFetcher {
+  private readonly logger = new Logger('Frontend config fetcher')
+
+  private frontendConfig: FrontendConfig | undefined = undefined
+
+  public async fetch(baseUrls: BaseUrls | undefined): Promise<FrontendConfig | undefined> {
+    if (!this.frontendConfig) {
+      if (baseUrls === undefined) {
+        return undefined
+      }
+      const baseUrl = baseUrls.editor.toString()
+      try {
+        this.frontendConfig = await getConfig(baseUrl)
+      } catch (error) {
+        this.logger.error(`Couldn't fetch frontend configuration from ${baseUrl}`, error)
+        return undefined
+      }
+      this.logger.info(`Fetched frontend config from ${baseUrl}`)
+    }
+    return this.frontendConfig
+  }
+}