feat(kit): add new `addServerScanDir` composable (#24001)

docs/3.api/5.kit/11.nitro.md

@@ -366,7 +366,7 @@ Add a directory to be scanned for auto-imports by Nitro.
 ### Type
 
 ```ts
-function function addServerImportsDir (dirs: string | string[], opts: { prepend?: boolean }): void
+function addServerImportsDir (dirs: string | string[], opts: { prepend?: boolean }): void
 ```
 
 ### Parameters
@@ -395,3 +395,40 @@ export default defineNuxtModule({
   }
 })
 ```
+
+## `addServerScanDir`
+
+Add directories to be scanned by Nitro. It will check for subdirectories, which will be registered
+just like the `~/server` folder is.
+
+### Type
+
+```ts
+function addServerScanDir (dirs: string | string[], opts: { prepend?: boolean }): void
+```
+
+### Parameters
+
+#### `dirs`
+
+**Type**: `string | string[]`
+
+**Required**: `true`
+
+A directory or an array of directories to register to be scanned for by Nitro as server dirs.
+
+### Examples
+
+```ts
+import { defineNuxtModule, addServerScanDir } from '@nuxt/kit'
+export default defineNuxtModule({
+  meta: {
+    name: 'my-module',
+    configKey: 'myModule',
+  },
+  setup(options) {
+    const resolver = createResolver(import.meta.url)
+    addServerScanDir(resolver.resolve('./runtime/server/routes'))
+  }
+})
+```

packages/kit/src/nitro.ts

@@ -110,3 +110,18 @@ export function addServerImportsDir (dirs: string | string[], opts: { prepend?:
     config.imports.dirs[opts.prepend ? 'unshift' : 'push'](..._dirs)
   })
 }
+
+/**
+ * Add directories to be scanned by Nitro. It will check for subdirectories,
+ * which will be registered just like the `~/server` folder is.
+ */
+export function addServerScanDir (dirs: string | string[], opts: { prepend?: boolean } = {}) {
+  const nuxt = useNuxt()
+  nuxt.hook('nitro:config', (config) => {
+    config.scanDirs = config.scanDirs || []
+
+    for (const dir of (Array.isArray(dirs) ? dirs : [dirs])) {
+      config.scanDirs[opts.prepend ? 'unshift' : 'push'](dir)
+    }
+  })
+}