fix: configure the default assetPrefix for MF apps correctly (#3094)

.changeset/happy-chefs-pay.md

@@ -0,0 +1,5 @@
+---
+'@module-federation/rsbuild-plugin': patch
+---
+
+fix: configure the default assetPrefix for MF apps correctly

packages/rsbuild-plugin/src/cli/index.ts

@@ -2,7 +2,7 @@ import { parseOptions } from '@module-federation/enhanced';
 import { ModuleFederationPlugin } from '@module-federation/enhanced/rspack';
 import { isRequiredVersion } from '@module-federation/sdk';
 
-import { isRegExp } from '../utils/index';
+import { isRegExp, DEFAULT_ASSET_PREFIX } from '../utils/index';
 import pkgJson from '../../package.json';
 
 import type {
@@ -44,16 +44,26 @@ export const pluginModuleFederation = (
     );
 
     api.modifyRsbuildConfig((config) => {
-      // If this is a provider app, Rsbuild should send the ws request to the provider's dev server.
-      // This allows the provider to do HMR when the provider module is loaded in the consumer's page.
-      if (
-        moduleFederationOptions.exposes &&
-        config.server?.port &&
-        !config.dev?.client?.port
-      ) {
+      // Change some default configs for remote modules
+      if (moduleFederationOptions.exposes) {
         config.dev ||= {};
-        config.dev.client ||= {};
-        config.dev.client.port = config.server.port;
+
+        // For remote modules, Rsbuild should send the ws request to the provider's dev server.
+        // This allows the provider to do HMR when the provider module is loaded in the consumer's page.
+        if (config.server?.port && !config.dev.client?.port) {
+          config.dev.client ||= {};
+          config.dev.client.port = config.server.port;
+        }
+
+        // Change the default assetPrefix to `true` for remote modules.
+        // This ensures that the remote module's assets can be requested by consumer apps with the correct URL.
+        const originalConfig = api.getRsbuildConfig('original');
+        if (
+          originalConfig.dev?.assetPrefix === undefined &&
+          config.dev.assetPrefix === DEFAULT_ASSET_PREFIX
+        ) {
+          config.dev.assetPrefix = true;
+        }
       }
     });
 
@@ -147,12 +157,6 @@ export const pluginModuleFederation = (
       if (!chain.output.get('uniqueName')) {
         chain.output.set('uniqueName', moduleFederationOptions.name);
       }
-
-      const publicPath = chain.output.get('publicPath');
-      // set the default publicPath to 'auto' to make MF work
-      if (publicPath === '/') {
-        chain.output.set('publicPath', 'auto');
-      }
     });
   },
 });

packages/rsbuild-plugin/src/utils/constant.ts

@@ -0,0 +1 @@
+export const DEFAULT_ASSET_PREFIX = '/';

packages/rsbuild-plugin/src/utils/index.ts

@@ -3,3 +3,5 @@ import util from 'util';
 export function isRegExp(target: any) {
   return util.types.isRegExp(target);
 }
+
+export * from './constant';