[nextra] support nextConfig.distDir (#1089)

* support `nextConfig.distDir`

* fix

.changeset/thin-bulldogs-enjoy.md

@@ -0,0 +1,5 @@
+---
+'nextra': patch
+---
+
+support `nextConfig.distDir`

examples/swr-site/next.config.js

@@ -5,14 +5,15 @@ const withNextra = require("nextra")({
     codeblocks: true,
   },
   staticImage: true,
-  defaultShowCopyCode: true
+  defaultShowCopyCode: true,
 });
 
 module.exports = withNextra({
   i18n: {
     locales: ["en-US", "es-ES", "ja", "ko", "ru", "zh-CN"],
     defaultLocale: "en-US",
   },
+  distDir: "./.next", // Nextra supports custom `nextConfig.distDir`
   redirects: () => {
     return [
       // {

packages/nextra/src/constants.ts

@@ -28,8 +28,4 @@ export const MARKDOWN_EXTENSIONS = ['md', 'mdx'] as const
 
 export const PUBLIC_DIR = path.join(CWD, 'public')
 
-export const CACHE_DIR = path.join(CWD, '.next', 'cache')
-
-export const ASSET_DIR = path.join(CWD, '.next', 'static', 'chunks')
-
 export const EXTERNAL_URL_REGEX = /^https?:\/\//

packages/nextra/src/content-dump.ts

@@ -1,24 +1,19 @@
 import path from 'node:path'
 import fs from 'graceful-fs'
 import { existsSync } from './file-system'
-import { ASSET_DIR, CACHE_DIR } from './constants'
+import { CWD } from './constants'
+
+let cacheDir: string
+let assetDir: string
+let cacheDirExist = false
 
 const asset: { [locale: string]: any } = Object.create(null)
 const cached = new Map<string, boolean>()
 
-if (!existsSync(ASSET_DIR)) {
-  fs.mkdirSync(ASSET_DIR, { recursive: true })
-}
-
-const cacheDirExist = existsSync(CACHE_DIR)
-if (!cacheDirExist) {
-  fs.mkdirSync(CACHE_DIR, { recursive: true })
-}
-
 function initFromCache(filename: string) {
   if (!cached.has(filename)) {
     try {
-      const content = fs.readFileSync(path.join(ASSET_DIR, filename), 'utf8')
+      const content = fs.readFileSync(path.join(assetDir, filename), 'utf8')
       cached.set(filename, true)
       return JSON.parse(content)
     } catch {
@@ -32,13 +27,18 @@ export function addPage({
   locale,
   route,
   title,
-  structurizedData
+  structurizedData,
+  distDir
 }: {
   locale: string
   route: string
   title: string
   structurizedData: any
+  distDir?: string
 }): void {
+  if (!cacheDir || !assetDir) {
+    initConfig(distDir)
+  }
   const dataFilename = `nextra-data-${locale}.json`
 
   asset[locale] ||= initFromCache(dataFilename)
@@ -51,23 +51,41 @@ export function addPage({
   // @TODO: introduce mutex lock, or only generate the asset when finishing the
   // entire build.
   const content = JSON.stringify(asset[locale])
-  fs.writeFileSync(path.join(ASSET_DIR, dataFilename), content)
-  fs.writeFileSync(path.join(CACHE_DIR, dataFilename), content)
+  fs.writeFileSync(path.join(assetDir, dataFilename), content)
+  fs.writeFileSync(path.join(cacheDir, dataFilename), content)
+}
+
+export function initConfig(distDir = '.next') {
+  cacheDir = path.join(CWD, distDir, 'cache')
+  assetDir = path.join(CWD, distDir, 'static', 'chunks')
 }
 
 // Copy cached data to the asset directory.
-export function restoreCache(): void {
+export function restoreCache(distDir?: string): void {
+  if (!cacheDir || !assetDir) {
+    initConfig(distDir)
+    if (!existsSync(assetDir)) {
+      fs.mkdirSync(assetDir, { recursive: true })
+    }
+
+    cacheDirExist = existsSync(cacheDir)
+    if (!cacheDirExist) {
+      fs.mkdirSync(cacheDir, { recursive: true })
+    }
+  }
+
   if (!cacheDirExist) {
     return
   }
-  if (!existsSync(ASSET_DIR)) {
-    fs.mkdirSync(ASSET_DIR, { recursive: true })
+
+  if (!existsSync(assetDir)) {
+    fs.mkdirSync(assetDir, { recursive: true })
   }
 
-  const files = fs.readdirSync(CACHE_DIR)
+  const files = fs.readdirSync(cacheDir)
   for (const file of files) {
     if (file.startsWith('nextra-data-')) {
-      fs.copyFileSync(path.join(CACHE_DIR, file), path.join(ASSET_DIR, file))
+      fs.copyFileSync(path.join(cacheDir, file), path.join(assetDir, file))
     }
   }
 }

packages/nextra/src/file-system.ts

@@ -1,17 +1,9 @@
-import fs from 'graceful-fs'
-import { findPagesDir } from 'next/dist/lib/find-pages-dir.js'
+import { findPagesDir, existsSync } from 'next/dist/lib/find-pages-dir.js'
 import { CWD } from './constants'
 
-export const existsSync = (filePath: string): boolean => {
-  try {
-    fs.statSync(filePath)
-    return true
-  } catch {
-    return false
-  }
-}
+export { existsSync }
 
-export const findPagesDirectory = (): string => {
+export function findPagesDirectory(): string {
   const res = findPagesDir(CWD, false)
   return (
     res.pagesDir || // next v13

packages/nextra/src/index.js

@@ -21,7 +21,10 @@ const nextra = (...config) =>
         : config[0]
     )
 
-    const nextraPlugin = new NextraPlugin(nextraConfig)
+    const nextraPlugin = new NextraPlugin({
+      ...nextraConfig,
+      distDir: nextConfig.distDir
+    })
 
     if (nextConfig.i18n?.locales) {
       console.log(
@@ -44,7 +47,8 @@ const nextra = (...config) =>
           locales: nextConfig.i18n?.locales || [DEFAULT_LOCALE],
           defaultLocale: nextConfig.i18n?.defaultLocale || DEFAULT_LOCALE,
           pageMapCache,
-          newNextLinkBehavior: nextConfig.experimental?.newNextLinkBehavior
+          newNextLinkBehavior: nextConfig.experimental?.newNextLinkBehavior,
+          distDir: nextConfig.distDir
         }
 
         config.module.rules.push(
@@ -78,11 +82,7 @@ const nextra = (...config) =>
           }
         )
 
-        if (typeof nextConfig.webpack === 'function') {
-          return nextConfig.webpack(config, options)
-        }
-
-        return config
+        return nextConfig.webpack?.(config, options) || config
       }
     }
   }

packages/nextra/src/loader.ts

@@ -71,7 +71,8 @@ async function loader(
     readingTime: _readingTime,
     mdxOptions,
     pageMapCache,
-    newNextLinkBehavior
+    newNextLinkBehavior,
+    distDir
   } = context.getOptions()
 
   context.cacheable(true)
@@ -158,7 +159,8 @@ export default MDXContent`.trimStart()
         locale: locale || DEFAULT_LOCALE,
         route,
         title,
-        structurizedData
+        structurizedData,
+        distDir
       })
     }
     indexContentEmitted.add(mdxPath)

packages/nextra/src/plugin.ts

@@ -163,15 +163,16 @@ export class PageMapCache {
 export const pageMapCache = new PageMapCache()
 
 export class NextraPlugin {
-  constructor(private config: NextraConfig) {}
+  constructor(private config: NextraConfig & { distDir?: string }) {}
 
   apply(compiler: Compiler) {
     compiler.hooks.beforeCompile.tapAsync(
       'NextraPlugin',
       async (_, callback) => {
-        if (this.config?.flexsearch) {
+        const { flexsearch, distDir } = this.config
+        if (flexsearch) {
           // Restore the search data from the cache.
-          restoreCache()
+          restoreCache(distDir)
         }
         const PAGES_DIR = findPagesDirectory()
         const result = await collectFiles(PAGES_DIR)

packages/nextra/src/types.ts

@@ -15,6 +15,7 @@ export interface LoaderOptions extends NextraConfig {
   defaultLocale: string
   pageMapCache: PageMapCache
   newNextLinkBehavior?: boolean
+  distDir?: string
 }
 
 export interface Folder<FileType = PageMapItem> {