fix(nuxt): Add Nitro Rollup plugin to inject Sentry server config (#15710)

Previously, the Sentry server config was added by adding another entry
point in the rollup options of Vite. Since Nuxt changed
`preserveModules` to `true`, this did not work anymore. The aim of this
change in Nuxt is to avoid duplicating what the Nitro build would do.

This means, that we now don't change the Rollup options in Vite anymore
(affects Nuxt as a whole) but only the Rollup options during the Nitro
build.

The added plugin will emit a new file and returns the Sentry config code
there.

fixes #15628

Author: s1gr1d

packages/nuxt/src/module.ts

@@ -113,7 +113,7 @@ export default defineNuxtModule<ModuleOptions>({
         });
 
         if (moduleOptions.autoInjectServerSentry !== 'experimental_dynamic-import') {
-          addServerConfigToBuild(moduleOptions, nuxt, nitro, serverConfigFile);
+          addServerConfigToBuild(moduleOptions, nitro, serverConfigFile);
 
           if (moduleOptions.debug) {
             const serverDirResolver = createResolver(nitro.options.output.serverDir);

packages/nuxt/src/vite/addServerConfig.ts

@@ -1,7 +1,6 @@
 import * as fs from 'fs';
 import { createResolver } from '@nuxt/kit';
-import type { Nuxt } from '@nuxt/schema';
-import { consoleSandbox } from '@sentry/core';
+import { consoleSandbox, logger } from '@sentry/core';
 import type { Nitro } from 'nitropack';
 import type { InputPluginOption } from 'rollup';
 import type { SentryNuxtModuleOptions } from '../common/types';
@@ -15,6 +14,7 @@ import {
   getFilenameFromNodeStartCommand,
   removeSentryQueryFromPath,
 } from './utils';
+import { existsSync } from 'node:fs';
 
 const SERVER_CONFIG_FILENAME = 'sentry.server.config';
 
@@ -26,19 +26,18 @@ const SERVER_CONFIG_FILENAME = 'sentry.server.config';
  */
 export function addServerConfigToBuild(
   moduleOptions: SentryNuxtModuleOptions,
-  nuxt: Nuxt,
   nitro: Nitro,
   serverConfigFile: string,
 ): void {
-  nuxt.hook('vite:extendConfig', async (viteInlineConfig, _env) => {
-    if (
-      typeof viteInlineConfig?.build?.rollupOptions?.input === 'object' &&
-      'server' in viteInlineConfig.build.rollupOptions.input
-    ) {
-      // Create a rollup entry for the server config to add it as `sentry.server.config.mjs` to the build
-      (viteInlineConfig.build.rollupOptions.input as { [entryName: string]: string })[SERVER_CONFIG_FILENAME] =
-        createResolver(nuxt.options.srcDir).resolve(`/${serverConfigFile}`);
+  nitro.hooks.hook('rollup:before', (nitro, rollupConfig) => {
+    if (rollupConfig?.plugins === null || rollupConfig?.plugins === undefined) {
+      rollupConfig.plugins = [];
+    } else if (!Array.isArray(rollupConfig.plugins)) {
+      // `rollupConfig.plugins` can be a single plugin, so we want to put it into an array so that we can push our own plugin
+      rollupConfig.plugins = [rollupConfig.plugins];
     }
+
+    rollupConfig.plugins.push(injectServerConfigPlugin(nitro, serverConfigFile, moduleOptions.debug));
   });
 
   /**
@@ -158,6 +157,45 @@ export function addDynamicImportEntryFileWrapper(
   );
 }
 
+/**
+ * Rollup plugin to include the Sentry server configuration file to the server build output.
+ */
+function injectServerConfigPlugin(nitro: Nitro, serverConfigFile: string, debug?: boolean): InputPluginOption {
+  const filePrefix = '\0virtual:sentry-server-config:';
+
+  return {
+    name: 'rollup-plugin-inject-sentry-server-config',
+
+    buildStart() {
+      const configPath = createResolver(nitro.options.srcDir).resolve(`/${serverConfigFile}`);
+
+      if (!existsSync(configPath)) {
+        if (debug) {
+          logger.log(`[Sentry] Sentry server config file not found: ${configPath}`);
+        }
+        return;
+      }
+
+      // Emitting a file adds it to the build output (Rollup is aware of the file, and we can later return the code in resolveId)
+      this.emitFile({
+        type: 'chunk',
+        id: `${filePrefix}${serverConfigFile}`,
+        fileName: `${SERVER_CONFIG_FILENAME}.mjs`,
+      });
+    },
+
+    resolveId(source) {
+      if (source.startsWith(filePrefix)) {
+        const originalFilePath = source.replace(filePrefix, '');
+        const configPath = createResolver(nitro.options.rootDir).resolve(`/${originalFilePath}`);
+
+        return { id: configPath };
+      }
+      return null;
+    },
+  };
+}
+
 /**
  * A Rollup plugin which wraps the server entry with a dynamic `import()`. This makes it possible to initialize Sentry first
  * by using a regular `import` and load the server after that.