feat(remix): support serving app under a sub-path via NEXT_PUBLIC_BASE_PATH (#2824)

apps/remix/app/components/forms/signin.tsx

@@ -1,5 +1,6 @@
 import { authClient } from '@documenso/auth/client';
 import { AuthenticationErrorCode } from '@documenso/auth/server/lib/errors/error-codes';
+import { formatPath } from '@documenso/lib/constants/app';
 import { AppError, AppErrorCode } from '@documenso/lib/errors/app-error';
 import { env } from '@documenso/lib/utils/env';
 import { zEmail } from '@documenso/lib/utils/zod';
@@ -44,7 +45,7 @@ const handleFallbackErrorMessages = (code: string) => {
   return message;
 };
 
-const LOGIN_REDIRECT_PATH = '/';
+const LOGIN_REDIRECT_PATH = formatPath('/');
 
 export const ZSignInFormSchema = z.object({
   email: zEmail().min(1),

apps/remix/app/components/general/app-command-menu.tsx

@@ -1,5 +1,6 @@
 import { useDebouncedValue } from '@documenso/lib/client-only/hooks/use-debounced-value';
 import { useSession } from '@documenso/lib/client-only/providers/session';
+import { formatPath } from '@documenso/lib/constants/app';
 import { SUPPORTED_LANGUAGES } from '@documenso/lib/constants/i18n';
 import {
   DOCUMENTS_PAGE_SHORTCUT,
@@ -862,7 +863,7 @@ const PromptLanguageCommands = ({
 
       formData.append('lang', lang);
 
-      const response = await fetch('/api/locale', {
+      const response = await fetch(formatPath('/api/locale'), {
         method: 'post',
         body: formData,
       });

apps/remix/app/components/general/document-signing/document-signing-auth-account.tsx

@@ -1,4 +1,5 @@
 import { authClient } from '@documenso/auth/client';
+import { formatPath } from '@documenso/lib/constants/app';
 import { Alert, AlertDescription } from '@documenso/ui/primitives/alert';
 import { Button } from '@documenso/ui/primitives/button';
 import { DialogFooter } from '@documenso/ui/primitives/dialog';
@@ -34,7 +35,9 @@ export const DocumentSigningAuthAccount = ({
       const currentPath = `${window.location.pathname}${window.location.search}${window.location.hash}`;
 
       await authClient.signOut({
-        redirectPath: `/signin?returnTo=${encodeURIComponent(currentPath)}#embedded=true&email=${isDirectTemplate ? '' : email}`,
+        redirectPath: formatPath(
+          `/signin?returnTo=${encodeURIComponent(currentPath)}#embedded=true&email=${isDirectTemplate ? '' : email}`,
+        ),
       });
     } catch {
       setIsSigningOut(false);

apps/remix/app/components/general/document-signing/document-signing-auth-page.tsx

@@ -1,4 +1,5 @@
 import { authClient } from '@documenso/auth/client';
+import { formatPath } from '@documenso/lib/constants/app';
 import { Button } from '@documenso/ui/primitives/button';
 import { useToast } from '@documenso/ui/primitives/use-toast';
 import { msg } from '@lingui/core/macro';
@@ -21,10 +22,10 @@ export const DocumentSigningAuthPageView = ({ email, emailHasAccount }: Document
     try {
       setIsSigningOut(true);
 
-      let redirectPath = '/signin';
+      let redirectPath = formatPath('/signin');
 
       if (email) {
-        redirectPath = emailHasAccount ? `/signin#email=${email}` : `/signup#email=${email}`;
+        redirectPath = emailHasAccount ? formatPath(`/signin#email=${email}`) : formatPath(`/signup#email=${email}`);
       }
 
       await authClient.signOut({

apps/remix/app/root.tsx

@@ -1,5 +1,6 @@
 import { getOptionalSession } from '@documenso/auth/server/lib/utils/get-session';
 import { SessionProvider } from '@documenso/lib/client-only/providers/session';
+import { getBasePath } from '@documenso/lib/constants/app';
 import { APP_I18N_OPTIONS, type SupportedLanguageCodes } from '@documenso/lib/constants/i18n';
 import { createPublicEnv } from '@documenso/lib/utils/env';
 import { extractLocaleData } from '@documenso/lib/utils/i18n';
@@ -20,7 +21,6 @@ import {
   useMatches,
 } from 'react-router';
 import { PreventFlashOnWrongTheme, ThemeProvider, useTheme } from 'remix-themes';
-
 import type { Route } from './+types/root';
 import stylesheet from './app.css?url';
 import { GenericErrorLayout } from './components/general/generic-error-layout';
@@ -68,6 +68,7 @@ export async function loader({ context, request }: Route.LoaderArgs) {
       lang,
       theme: getTheme(),
       disableAnimations,
+      basePath: getBasePath(),
       // Surface the per-request CSP nonce produced by `securityHeadersMiddleware` so all
       // SSR-rendered <script>/<style> elements in this layout (and child
       // routes that need it) can carry the matching nonce attribute.
@@ -90,10 +91,10 @@ export async function loader({ context, request }: Route.LoaderArgs) {
 }
 
 export function Layout({ children }: { children: React.ReactNode }) {
-  const { theme } = useLoaderData<typeof loader>() || {};
+  const { theme, basePath } = useLoaderData<typeof loader>() || {};
 
   return (
-    <ThemeProvider specifiedTheme={theme} themeAction="/api/theme">
+    <ThemeProvider specifiedTheme={theme} themeAction={`${basePath ?? ''}/api/theme`}>
       <LayoutContent>{children}</LayoutContent>
     </ThemeProvider>
   );
@@ -111,6 +112,8 @@ export function LayoutContent({ children }: { children: React.ReactNode }) {
 
   const [theme] = useTheme();
 
+  const basePath = data.basePath ?? '';
+
   // Recipient routes (signing pages) put `documenso-branded` on <body> so the
   // <style> block from `RecipientBranding` applies to BOTH the main tree and
   // any portaled content (Radix dialogs/popovers/dropdowns mount outside the
@@ -126,11 +129,11 @@ export function LayoutContent({ children }: { children: React.ReactNode }) {
     <html translate="no" lang={lang} data-theme={theme} className={theme ?? ''} suppressHydrationWarning>
       <head>
         <meta charSet="utf-8" />
-        <link rel="apple-touch-icon" sizes="180x180" href="/apple-touch-icon.png" />
-        <link rel="icon" type="image/png" sizes="32x32" href="/favicon-32x32.png" />
-        <link rel="icon" type="image/png" sizes="16x16" href="/favicon-16x16.png" />
+        <link rel="apple-touch-icon" sizes="180x180" href={`${basePath}/apple-touch-icon.png`} />
+        <link rel="icon" type="image/png" sizes="32x32" href={`${basePath}/favicon-32x32.png`} />
+        <link rel="icon" type="image/png" sizes="16x16" href={`${basePath}/favicon-16x16.png`} />
         <meta name="viewport" content="width=device-width, initial-scale=1" />
-        <link rel="manifest" href="/site.webmanifest" />
+        <link rel="manifest" href={`${basePath}/site.webmanifest`} />
         <meta name="google" content="notranslate" />
         <Meta />
         <Links nonce={nonce(cspNonce)} />

apps/remix/app/routes/embed+/playground.tsx

@@ -5,8 +5,9 @@
  *
  * No translations required.
  */
-import { useCallback, useEffect, useRef, useState } from 'react';
 
+import { formatPath } from '@documenso/lib/constants/app';
+import { useCallback, useEffect, useRef, useState } from 'react';
 import { useNavigate, useSearchParams } from 'react-router';
 
 export const loader = () => {
@@ -147,7 +148,7 @@ export default function EmbedPlaygroundPage() {
       return inputToken;
     }
 
-    const response = await fetch('/api/v2/embedding/create-presign-token', {
+    const response = await fetch(formatPath('/api/v2/embedding/create-presign-token'), {
       method: 'POST',
       headers: {
         Authorization: `Bearer ${inputToken}`,

apps/remix/public/site.webmanifest

@@ -3,12 +3,12 @@
   "short_name": "Documenso",
   "icons": [
     {
-      "src": "/android-chrome-192x192.png",
+      "src": "./android-chrome-192x192.png",
       "sizes": "192x192",
       "type": "image/png"
     },
     {
-      "src": "/android-chrome-512x512.png",
+      "src": "./android-chrome-512x512.png",
       "sizes": "512x512",
       "type": "image/png"
     }

apps/remix/react-router.config.ts

@@ -3,4 +3,9 @@ import type { Config } from '@react-router/dev/config';
 export default {
   appDirectory: 'app',
   ssr: true,
+  // Must never be undefined and must start with the raw Vite `base` value,
+  // otherwise @react-router/dev crashes / exits on `react-router dev`. Both are
+  // kept without a trailing slash so they match exactly, and so the bare
+  // sub-path URL (e.g. "/ESign") still matches the basename at runtime.
+  basename: process.env.NEXT_PUBLIC_BASE_PATH ? process.env.NEXT_PUBLIC_BASE_PATH.replace(/\/$/, '') : '/',
 } satisfies Config;

apps/remix/server/api/ai/detect-fields.client.ts

@@ -1,3 +1,4 @@
+import { formatPath } from '@documenso/lib/constants/app';
 import { z } from 'zod';
 
 import { type TDetectFieldsRequest, ZNormalizedFieldWithContextSchema } from './detect-fields.types';
@@ -69,7 +70,7 @@ export const detectFields = async ({
   onError,
   signal,
 }: DetectFieldsOptions): Promise<void> => {
-  const response = await fetch('/api/ai/detect-fields', {
+  const response = await fetch(formatPath('/api/ai/detect-fields'), {
     method: 'POST',
     headers: {
       'Content-Type': 'application/json',

apps/remix/server/api/ai/detect-recipients.client.ts

@@ -1,3 +1,4 @@
+import { formatPath } from '@documenso/lib/constants/app';
 import { ZDetectedRecipientSchema } from '@documenso/lib/server-only/ai/envelope/detect-recipients/schema';
 import { z } from 'zod';
 
@@ -70,7 +71,7 @@ export const detectRecipients = async ({
   onError,
   signal,
 }: DetectRecipientsOptions): Promise<void> => {
-  const response = await fetch('/api/ai/detect-recipients', {
+  const response = await fetch(formatPath('/api/ai/detect-recipients'), {
     method: 'POST',
     headers: {
       'Content-Type': 'application/json',

apps/remix/server/main.js

@@ -14,9 +14,22 @@ import { getLoadContext } from './hono/server/load-context.js';
 import server from './hono/server/router.js';
 import * as build from './index.js';
 
+// Sub-path the app is served under (e.g. "/ESign"). Empty = root.
+// Must match the basePath used by the Hono router and the Vite `base`/RR
+// `basename` so that hashed asset URLs like `/ESign/assets/app-xxx.css`
+// resolve to files on disk at `build/client/assets/app-xxx.css`.
+const basePath = (process.env.NEXT_PUBLIC_BASE_PATH ?? '').replace(/\/$/, '');
+
 server.use(
   serveStatic({
     root: 'build/client',
+    rewriteRequestPath: (path) => {
+      if (basePath && (path === basePath || path.startsWith(`${basePath}/`))) {
+        const stripped = path.slice(basePath.length);
+        return stripped === '' ? '/' : stripped;
+      }
+      return path;
+    },
     onFound: (path, c) => {
       if (path.startsWith('build/client/assets')) {
         // Hard cache assets with hashed file names.

apps/remix/server/router.ts

@@ -46,7 +46,9 @@ export interface HonoEnv {
   };
 }
 
-const app = new Hono<HonoEnv>();
+const basePath = (env('NEXT_PUBLIC_BASE_PATH') ?? '').replace(/\/$/, '');
+
+const app = new Hono<HonoEnv>().basePath(basePath || '/');
 
 /**
  * Database-backed rate limiting for API routes.

apps/remix/server/trpc/hono-trpc-open-api.ts

@@ -1,4 +1,4 @@
-import { API_V2_BETA_URL, API_V2_URL } from '@documenso/lib/constants/app';
+import { API_V2_BETA_URL, API_V2_URL, formatPath } from '@documenso/lib/constants/app';
 import { AppError, genericErrorCodeToTrpcErrorCodeMap } from '@documenso/lib/errors/app-error';
 import { createTrpcContext } from '@documenso/trpc/server/context';
 import { appRouter } from '@documenso/trpc/server/router';
@@ -11,8 +11,10 @@ type OpenApiTrpcServerHandlerOptions = {
 };
 
 export const openApiTrpcServerHandler = async (c: Context, { isBeta }: OpenApiTrpcServerHandlerOptions) => {
+  const endpoint = formatPath(isBeta ? API_V2_BETA_URL : API_V2_URL) as `/${string}`;
+
   return createOpenApiFetchHandler<typeof appRouter>({
-    endpoint: isBeta ? API_V2_BETA_URL : API_V2_URL,
+    endpoint,
     router: appRouter,
     createContext: async () => createTrpcContext({ c, requestSource: 'apiV2' }),
     req: c.req.raw,

apps/remix/server/trpc/hono-trpc-remix.ts

@@ -1,3 +1,4 @@
+import { formatPath } from '@documenso/lib/constants/app';
 import { createTrpcContext } from '@documenso/trpc/server/context';
 import { appRouter } from '@documenso/trpc/server/router';
 import { handleTrpcRouterError } from '@documenso/trpc/utils/trpc-error-handler';
@@ -5,10 +6,14 @@ import { trpcServer } from '@hono/trpc-server';
 
 /**
  * Trpc server for internal routes like /api/trpc/*
+ *
+ * `endpoint` must include the sub-path prefix (e.g. "/ESign") because the
+ * @hono/trpc-server adapter slices the prefix off the full URL pathname to
+ * compute the procedure name. Hono's `basePath` doesn't rewrite the URL.
  */
 export const reactRouterTrpcServer = trpcServer({
   router: appRouter,
-  endpoint: '/api/trpc',
+  endpoint: formatPath('/api/trpc'),
   createContext: async (_, c) => createTrpcContext({ c, requestSource: 'app' }),
   onError: (opts) => handleTrpcRouterError(opts, 'trpc'),
 });

apps/remix/vite.config.ts

@@ -23,6 +23,10 @@ const cMapsDir = normalizePath(path.join(pdfjsDistPath, 'cmaps'));
  * Do not configure any envs here.
  */
 export default defineConfig({
+  // No trailing slash: the React Router dev server requires its `basename` to
+  // start with this raw value (see react-router.config.ts). Vite normalizes
+  // and joins asset URLs correctly either way.
+  base: process.env.NEXT_PUBLIC_BASE_PATH ? process.env.NEXT_PUBLIC_BASE_PATH.replace(/\/$/, '') : '/',
   css: {
     postcss: {
       plugins: [tailwindcss, autoprefixer],