feat: support custom redirect base url for nuxt sdk (#793)

.changeset/good-knives-clap.md

@@ -0,0 +1,5 @@
+---
+"@logto/nuxt": minor
+---
+
+support custom redirect base url settings for nuxt SDK

packages/nuxt/src/runtime/server/event-handler.ts

@@ -20,6 +20,7 @@ export default defineEventHandler(async (event) => {
     pathnames,
     postCallbackRedirectUri,
     postLogoutRedirectUri,
+    customRedirectBaseUrl,
     ...clientConfig
   } = logtoConfig;
 
@@ -36,7 +37,21 @@ export default defineEventHandler(async (event) => {
     );
   }
 
-  const url = getRequestURL(event);
+  const requestUrl = getRequestURL(event);
+
+  /**
+   * This approach allows us to:
+   * 1. Override the base URL when necessary (e.g., in proxy environments)
+   * 2. Preserve the original path and query parameters
+   * 3. Fall back to the original URL when no custom base is provided
+   *
+   * It's particularly useful in scenarios where the application is deployed
+   * behind a reverse proxy or in environments that rewrite URLs.
+   */
+  const url = customRedirectBaseUrl
+    ? new URL(requestUrl.pathname + requestUrl.search + requestUrl.hash, customRedirectBaseUrl)
+    : requestUrl;
+
   const storage = new CookieStorage({
     cookieKey: cookieName,
     encryptionKey: cookieEncryptionKey,

packages/nuxt/src/runtime/utils/constants.ts

@@ -12,4 +12,5 @@ export const defaults = Object.freeze({
   appId: '<replace-with-logto-app-id>',
   appSecret: '<replace-with-logto-app-secret>',
   cookieEncryptionKey: '<replace-with-random-string>',
+  customRedirectBaseUrl: '<replace-with-custom-redirect-base-url>',
 } as const satisfies LogtoRuntimeConfigInput);

packages/nuxt/src/runtime/utils/types.ts

@@ -78,6 +78,21 @@ export type LogtoRuntimeConfig = LogtoModuleOptions & {
    * The secret used to encrypt the Logto cookie. It should be a random string.
    */
   cookieEncryptionKey: string;
+  /**
+   * Custom base URL for redirects
+   *
+   * This URL is used as the base for generating redirect and callback URLs.
+   * It's particularly useful in environments where the application is behind
+   * a proxy or where URLs are rewritten.
+   *
+   * If set, this value will be used instead of the automatically detected URL.
+   * If not set, the system will use the URL obtained from `getRequestURL`.
+   *
+   * Example: 'https://your-public-facing-domain.com'
+   *
+   * Note: Provide only the base URL without paths or query parameters.
+   */
+  customRedirectBaseUrl: string;
 } & Omit<LogtoConfig, 'appSecret'> &
   Required<Pick<LogtoConfig, 'appSecret'>>;