rsnext/packages/next/server/next-dev-server.ts
JJ Kasper d130f63c41
Add handling fo beforeFiles, afterFiles, and fallback rewrites (#23407)
This adds support for returning an object from `rewrites` in `next.config.js` with `beforeFiles`, `afterFiles`, and `fallback` to allow specifying rewrites at different stages of routing. The existing support for returning an array for rewrites is still supported and behaves the same way. The documentation has been updated to include information on these new stages that can be rewritten and removes the outdated note of rewrites not being able to override pages. 



## Bug

- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added

## Feature

- [ ] Implements an existing feature request or RFC. Make sure the feature request has been accepted for implementation before opening a PR.
- [ ] Related issues linked using `fixes #number`
- [x] Integration tests added
- [x] Documentation added
- [ ] Telemetry added. In case of a feature if it's used or not.

## Documentation / Examples

- [ ] Make sure the linting passes
2021-03-26 15:19:48 +00:00

758 lines
23 KiB
TypeScript

import { ReactDevOverlay } from '@next/react-dev-overlay/lib/client'
import crypto from 'crypto'
import fs from 'fs'
import { IncomingMessage, ServerResponse } from 'http'
import { Worker } from 'jest-worker'
import AmpHtmlValidator from 'next/dist/compiled/amphtml-validator'
import findUp from 'next/dist/compiled/find-up'
import { join as pathJoin, relative, resolve as pathResolve, sep } from 'path'
import React from 'react'
import { UrlWithParsedQuery } from 'url'
import Watchpack from 'watchpack'
import { ampValidation } from '../build/output/index'
import * as Log from '../build/output/log'
import { PUBLIC_DIR_MIDDLEWARE_CONFLICT } from '../lib/constants'
import { fileExists } from '../lib/file-exists'
import { findPagesDir } from '../lib/find-pages-dir'
import loadCustomRoutes, { CustomRoutes } from '../lib/load-custom-routes'
import { verifyTypeScriptSetup } from '../lib/verifyTypeScriptSetup'
import {
PHASE_DEVELOPMENT_SERVER,
CLIENT_STATIC_FILES_PATH,
DEV_CLIENT_PAGES_MANIFEST,
STATIC_STATUS_PAGES,
} from '../next-server/lib/constants'
import {
getRouteMatcher,
getRouteRegex,
getSortedRoutes,
isDynamicRoute,
} from '../next-server/lib/router/utils'
import { __ApiPreviewProps } from '../next-server/server/api-utils'
import Server, { ServerConstructor } from '../next-server/server/next-server'
import { normalizePagePath } from '../next-server/server/normalize-page-path'
import Router, { Params, route } from '../next-server/server/router'
import { eventCliSession } from '../telemetry/events'
import { Telemetry } from '../telemetry/storage'
import { setGlobal } from '../telemetry/trace'
import HotReloader from './hot-reloader'
import { findPageFile } from './lib/find-page-file'
import { getNodeOptionsWithoutInspect } from './lib/utils'
import { withCoalescedInvoke } from '../lib/coalesced-function'
import { NextConfig } from '../next-server/server/config'
if (typeof React.Suspense === 'undefined') {
throw new Error(
`The version of React you are using is lower than the minimum required version needed for Next.js. Please upgrade "react" and "react-dom": "npm install react react-dom" https://err.sh/vercel/next.js/invalid-react-version`
)
}
export default class DevServer extends Server {
private devReady: Promise<void>
private setDevReady?: Function
private webpackWatcher?: Watchpack | null
private hotReloader?: HotReloader
private isCustomServer: boolean
protected sortedRoutes?: string[]
protected staticPathsWorker: import('jest-worker').Worker & {
loadStaticPaths: typeof import('./static-paths-worker').loadStaticPaths
}
constructor(
options: ServerConstructor & {
conf: NextConfig
isNextDevCommand?: boolean
}
) {
super({ ...options, dev: true })
this.renderOpts.dev = true
;(this.renderOpts as any).ErrorDebug = ReactDevOverlay
this.devReady = new Promise((resolve) => {
this.setDevReady = resolve
})
;(this.renderOpts as any).ampSkipValidation =
this.nextConfig.experimental?.amp?.skipValidation ?? false
;(this.renderOpts as any).ampValidator = (
html: string,
pathname: string
) => {
const validatorPath =
this.nextConfig.experimental &&
this.nextConfig.experimental.amp &&
this.nextConfig.experimental.amp.validator
return AmpHtmlValidator.getInstance(validatorPath).then((validator) => {
const result = validator.validateString(html)
ampValidation(
pathname,
result.errors
.filter((e) => e.severity === 'ERROR')
.filter((e) => this._filterAmpDevelopmentScript(html, e)),
result.errors.filter((e) => e.severity !== 'ERROR')
)
})
}
if (fs.existsSync(pathJoin(this.dir, 'static'))) {
console.warn(
`The static directory has been deprecated in favor of the public directory. https://err.sh/vercel/next.js/static-dir-deprecated`
)
}
this.isCustomServer = !options.isNextDevCommand
this.pagesDir = findPagesDir(this.dir)
this.staticPathsWorker = new Worker(
require.resolve('./static-paths-worker'),
{
maxRetries: 1,
numWorkers: this.nextConfig.experimental.cpus,
forkOptions: {
env: {
...process.env,
// discard --inspect/--inspect-brk flags from process.env.NODE_OPTIONS. Otherwise multiple Node.js debuggers
// would be started if user launch Next.js in debugging mode. The number of debuggers is linked to
// the number of workers Next.js tries to launch. The only worker users are interested in debugging
// is the main Next.js one
NODE_OPTIONS: getNodeOptionsWithoutInspect(),
},
},
}
) as Worker & {
loadStaticPaths: typeof import('./static-paths-worker').loadStaticPaths
}
this.staticPathsWorker.getStdout().pipe(process.stdout)
this.staticPathsWorker.getStderr().pipe(process.stderr)
}
protected readBuildId(): string {
return 'development'
}
async addExportPathMapRoutes() {
// Makes `next export` exportPathMap work in development mode.
// So that the user doesn't have to define a custom server reading the exportPathMap
if (this.nextConfig.exportPathMap) {
console.log('Defining routes from exportPathMap')
const exportPathMap = await this.nextConfig.exportPathMap(
{},
{
dev: true,
dir: this.dir,
outDir: null,
distDir: this.distDir,
buildId: this.buildId,
}
) // In development we can't give a default path mapping
for (const path in exportPathMap) {
const { page, query = {} } = exportPathMap[path]
// We use unshift so that we're sure the routes is defined before Next's default routes
this.router.addFsRoute({
match: route(path),
type: 'route',
name: `${path} exportpathmap route`,
fn: async (req, res, _params, parsedUrl) => {
const { query: urlQuery } = parsedUrl
Object.keys(urlQuery)
.filter((key) => query[key] === undefined)
.forEach((key) =>
console.warn(
`Url '${path}' defines a query parameter '${key}' that is missing in exportPathMap`
)
)
const mergedQuery = { ...urlQuery, ...query }
await this.render(req, res, page, mergedQuery, parsedUrl)
return {
finished: true,
}
},
})
}
}
}
async startWatcher(): Promise<void> {
if (this.webpackWatcher) {
return
}
const regexPageExtension = new RegExp(
`\\.+(?:${this.nextConfig.pageExtensions.join('|')})$`
)
let resolved = false
return new Promise((resolve, reject) => {
const pagesDir = this.pagesDir
// Watchpack doesn't emit an event for an empty directory
fs.readdir(pagesDir!, (_, files) => {
if (files?.length) {
return
}
if (!resolved) {
resolve()
resolved = true
}
})
let wp = (this.webpackWatcher = new Watchpack())
wp.watch([], [pagesDir!], 0)
wp.on('aggregated', () => {
const routedPages = []
const knownFiles = wp.getTimeInfoEntries()
for (const [fileName, { accuracy }] of knownFiles) {
if (accuracy === undefined || !regexPageExtension.test(fileName)) {
continue
}
let pageName =
'/' + relative(pagesDir!, fileName).replace(/\\+/g, '/')
pageName = pageName.replace(regexPageExtension, '')
pageName = pageName.replace(/\/index$/, '') || '/'
routedPages.push(pageName)
}
try {
// we serve a separate manifest with all pages for the client in
// dev mode so that we can match a page after a rewrite on the client
// before it has been built and is populated in the _buildManifest
const sortedRoutes = getSortedRoutes(routedPages)
if (
!this.sortedRoutes?.every((val, idx) => val === sortedRoutes[idx])
) {
// emit the change so clients fetch the update
this.hotReloader!.send(undefined, { devPagesManifest: true })
}
this.sortedRoutes = sortedRoutes
this.dynamicRoutes = this.sortedRoutes
.filter(isDynamicRoute)
.map((page) => ({
page,
match: getRouteMatcher(getRouteRegex(page)),
}))
this.router.setDynamicRoutes(this.dynamicRoutes)
if (!resolved) {
resolve()
resolved = true
}
} catch (e) {
if (!resolved) {
reject(e)
resolved = true
} else {
console.warn('Failed to reload dynamic routes:', e)
}
}
})
})
}
async stopWatcher(): Promise<void> {
if (!this.webpackWatcher) {
return
}
this.webpackWatcher.close()
this.webpackWatcher = null
}
async prepare(): Promise<void> {
await verifyTypeScriptSetup(this.dir, this.pagesDir!, false)
this.customRoutes = await loadCustomRoutes(this.nextConfig)
// reload router
const { redirects, rewrites, headers } = this.customRoutes
if (
rewrites.beforeFiles.length ||
rewrites.afterFiles.length ||
rewrites.fallback.length ||
redirects.length ||
headers.length
) {
this.router = new Router(this.generateRoutes())
}
this.hotReloader = new HotReloader(this.dir, {
pagesDir: this.pagesDir!,
config: this.nextConfig,
previewProps: this.getPreviewProps(),
buildId: this.buildId,
rewrites,
})
await super.prepare()
await this.addExportPathMapRoutes()
await this.hotReloader.start()
await this.startWatcher()
this.setDevReady!()
const telemetry = new Telemetry({ distDir: this.distDir })
telemetry.record(
eventCliSession(PHASE_DEVELOPMENT_SERVER, this.distDir, {
cliCommand: 'dev',
isSrcDir: relative(this.dir, this.pagesDir!).startsWith('src'),
hasNowJson: !!(await findUp('now.json', { cwd: this.dir })),
isCustomServer: this.isCustomServer,
})
)
// This is required by the tracing subsystem.
setGlobal('telemetry', telemetry)
}
protected async close(): Promise<void> {
await this.stopWatcher()
await this.staticPathsWorker.end()
if (this.hotReloader) {
await this.hotReloader.stop()
}
}
protected async hasPage(pathname: string): Promise<boolean> {
let normalizedPath: string
try {
normalizedPath = normalizePagePath(pathname)
} catch (err) {
console.error(err)
// if normalizing the page fails it means it isn't valid
// so it doesn't exist so don't throw and return false
// to ensure we return 404 instead of 500
return false
}
const pageFile = await findPageFile(
this.pagesDir!,
normalizedPath,
this.nextConfig.pageExtensions
)
return !!pageFile
}
protected async _beforeCatchAllRender(
req: IncomingMessage,
res: ServerResponse,
params: Params,
parsedUrl: UrlWithParsedQuery
): Promise<boolean> {
const { pathname } = parsedUrl
const pathParts = params.path || []
const path = `/${pathParts.join('/')}`
// check for a public file, throwing error if there's a
// conflicting page
let decodedPath: string
try {
decodedPath = decodeURIComponent(path)
} catch (_) {
const err: Error & { code?: string } = new Error('failed to decode param')
err.code = 'DECODE_FAILED'
throw err
}
if (await this.hasPublicFile(decodedPath)) {
if (await this.hasPage(pathname!)) {
const err = new Error(
`A conflicting public file and page file was found for path ${pathname} https://err.sh/vercel/next.js/conflicting-public-file-page`
)
res.statusCode = 500
await this.renderError(err, req, res, pathname!, {})
return true
}
await this.servePublic(req, res, pathParts)
return true
}
return false
}
async run(
req: IncomingMessage,
res: ServerResponse,
parsedUrl: UrlWithParsedQuery
): Promise<void> {
await this.devReady
const { basePath } = this.nextConfig
let originalPathname: string | null = null
if (basePath && parsedUrl.pathname?.startsWith(basePath)) {
// strip basePath before handling dev bundles
// If replace ends up replacing the full url it'll be `undefined`, meaning we have to default it to `/`
originalPathname = parsedUrl.pathname
parsedUrl.pathname = parsedUrl.pathname!.slice(basePath.length) || '/'
}
const { pathname } = parsedUrl
if (pathname!.startsWith('/_next')) {
if (await fileExists(pathJoin(this.publicDir, '_next'))) {
throw new Error(PUBLIC_DIR_MIDDLEWARE_CONFLICT)
}
}
const { finished = false } = await this.hotReloader!.run(
req,
res,
parsedUrl
)
if (finished) {
return
}
if (originalPathname) {
// restore the path before continuing so that custom-routes can accurately determine
// if they should match against the basePath or not
parsedUrl.pathname = originalPathname
}
return super.run(req, res, parsedUrl)
}
// override production loading of routes-manifest
protected getCustomRoutes(): CustomRoutes {
// actual routes will be loaded asynchronously during .prepare()
return {
redirects: [],
rewrites: { beforeFiles: [], afterFiles: [], fallback: [] },
headers: [],
}
}
private _devCachedPreviewProps: __ApiPreviewProps | undefined
protected getPreviewProps() {
if (this._devCachedPreviewProps) {
return this._devCachedPreviewProps
}
return (this._devCachedPreviewProps = {
previewModeId: crypto.randomBytes(16).toString('hex'),
previewModeSigningKey: crypto.randomBytes(32).toString('hex'),
previewModeEncryptionKey: crypto.randomBytes(32).toString('hex'),
})
}
generateRoutes() {
const { fsRoutes, ...otherRoutes } = super.generateRoutes()
// In development we expose all compiled files for react-error-overlay's line show feature
// We use unshift so that we're sure the routes is defined before Next's default routes
fsRoutes.unshift({
match: route('/_next/development/:path*'),
type: 'route',
name: '_next/development catchall',
fn: async (req, res, params) => {
const p = pathJoin(this.distDir, ...(params.path || []))
await this.serveStatic(req, res, p)
return {
finished: true,
}
},
})
fsRoutes.unshift({
match: route(
`/_next/${CLIENT_STATIC_FILES_PATH}/${this.buildId}/${DEV_CLIENT_PAGES_MANIFEST}`
),
type: 'route',
name: `_next/${CLIENT_STATIC_FILES_PATH}/${this.buildId}/${DEV_CLIENT_PAGES_MANIFEST}`,
fn: async (_req, res) => {
res.statusCode = 200
res.setHeader('Content-Type', 'application/json; charset=utf-8')
res.end(
JSON.stringify({
pages: this.sortedRoutes,
})
)
return {
finished: true,
}
},
})
fsRoutes.push({
match: route('/:path*'),
type: 'route',
requireBasePath: false,
name: 'catchall public directory route',
fn: async (req, res, params, parsedUrl) => {
const { pathname } = parsedUrl
if (!pathname) {
throw new Error('pathname is undefined')
}
// Used in development to check public directory paths
if (await this._beforeCatchAllRender(req, res, params, parsedUrl)) {
return {
finished: true,
}
}
return {
finished: false,
}
},
})
return { fsRoutes, ...otherRoutes }
}
// In development public files are not added to the router but handled as a fallback instead
protected generatePublicRoutes(): never[] {
return []
}
// In development dynamic routes cannot be known ahead of time
protected getDynamicRoutes(): never[] {
return []
}
_filterAmpDevelopmentScript(
html: string,
event: { line: number; col: number; code: string }
): boolean {
if (event.code !== 'DISALLOWED_SCRIPT_TAG') {
return true
}
const snippetChunks = html.split('\n')
let snippet
if (
!(snippet = html.split('\n')[event.line - 1]) ||
!(snippet = snippet.substring(event.col))
) {
return true
}
snippet = snippet + snippetChunks.slice(event.line).join('\n')
snippet = snippet.substring(0, snippet.indexOf('</script>'))
return !snippet.includes('data-amp-development-mode-only')
}
protected async getStaticPaths(
pathname: string
): Promise<{
staticPaths: string[] | undefined
fallbackMode: false | 'static' | 'blocking'
}> {
// we lazy load the staticPaths to prevent the user
// from waiting on them for the page to load in dev mode
const __getStaticPaths = async () => {
const { publicRuntimeConfig, serverRuntimeConfig } = this.nextConfig
const { locales, defaultLocale } = this.nextConfig.i18n || {}
const paths = await this.staticPathsWorker.loadStaticPaths(
this.distDir,
pathname,
!this.renderOpts.dev && this._isLikeServerless,
{
publicRuntimeConfig,
serverRuntimeConfig,
},
locales,
defaultLocale
)
return paths
}
const { paths: staticPaths, fallback } = (
await withCoalescedInvoke(__getStaticPaths)(`staticPaths-${pathname}`, [])
).value
return {
staticPaths,
fallbackMode:
fallback === 'blocking'
? 'blocking'
: fallback === true
? 'static'
: false,
}
}
protected async ensureApiPage(pathname: string) {
return this.hotReloader!.ensurePage(pathname)
}
async renderToHTML(
req: IncomingMessage,
res: ServerResponse,
pathname: string,
query: { [key: string]: string }
): Promise<string | null> {
await this.devReady
const compilationErr = await this.getCompilationError(pathname)
if (compilationErr) {
res.statusCode = 500
return this.renderErrorToHTML(compilationErr, req, res, pathname, query)
}
// In dev mode we use on demand entries to compile the page before rendering
try {
await this.hotReloader!.ensurePage(pathname).catch(async (err: Error) => {
if ((err as any).code !== 'ENOENT') {
throw err
}
for (const dynamicRoute of this.dynamicRoutes || []) {
const params = dynamicRoute.match(pathname)
if (!params) {
continue
}
return this.hotReloader!.ensurePage(dynamicRoute.page)
}
throw err
})
} catch (err) {
if (err.code === 'ENOENT') {
try {
await this.hotReloader!.ensurePage('/404')
} catch (hotReloaderError) {
if (hotReloaderError.code !== 'ENOENT') {
throw hotReloaderError
}
}
res.statusCode = 404
return this.renderErrorToHTML(null, req, res, pathname, query)
}
if (!this.quiet) console.error(err)
}
const html = await super.renderToHTML(req, res, pathname, query)
return html
}
async renderErrorToHTML(
err: Error | null,
req: IncomingMessage,
res: ServerResponse,
pathname: string,
query: { [key: string]: string }
): Promise<string | null> {
await this.devReady
if (res.statusCode === 404 && (await this.hasPage('/404'))) {
await this.hotReloader!.ensurePage('/404')
} else if (
STATIC_STATUS_PAGES.includes(`/${res.statusCode}`) &&
(await this.hasPage(`/${res.statusCode}`))
) {
await this.hotReloader!.ensurePage(`/${res.statusCode}`)
} else {
await this.hotReloader!.ensurePage('/_error')
}
const compilationErr = await this.getCompilationError(pathname)
if (compilationErr) {
res.statusCode = 500
return super.renderErrorToHTML(compilationErr, req, res, pathname, query)
}
if (!err && res.statusCode === 500) {
err = new Error(
'An undefined error was thrown sometime during render... ' +
'See https://err.sh/vercel/next.js/threw-undefined'
)
}
try {
const out = await super.renderErrorToHTML(err, req, res, pathname, query)
return out
} catch (err2) {
if (!this.quiet) Log.error(err2)
res.statusCode = 500
return super.renderErrorToHTML(err2, req, res, pathname, query)
}
}
sendHTML(
req: IncomingMessage,
res: ServerResponse,
html: string
): Promise<void> {
// In dev, we should not cache pages for any reason.
res.setHeader('Cache-Control', 'no-store, must-revalidate')
return super.sendHTML(req, res, html)
}
protected setImmutableAssetCacheControl(res: ServerResponse): void {
res.setHeader('Cache-Control', 'no-store, must-revalidate')
}
private servePublic(
req: IncomingMessage,
res: ServerResponse,
pathParts: string[]
): Promise<void> {
const p = pathJoin(this.publicDir, ...pathParts)
return this.serveStatic(req, res, p)
}
async hasPublicFile(path: string): Promise<boolean> {
try {
const info = await fs.promises.stat(pathJoin(this.publicDir, path))
return info.isFile()
} catch (_) {
return false
}
}
async getCompilationError(page: string): Promise<any> {
const errors = await this.hotReloader!.getCompilationErrors(page)
if (errors.length === 0) return
// Return the very first error we found.
return errors[0]
}
protected isServeableUrl(untrustedFileUrl: string): boolean {
// This method mimics what the version of `send` we use does:
// 1. decodeURIComponent:
// https://github.com/pillarjs/send/blob/0.17.1/index.js#L989
// https://github.com/pillarjs/send/blob/0.17.1/index.js#L518-L522
// 2. resolve:
// https://github.com/pillarjs/send/blob/de073ed3237ade9ff71c61673a34474b30e5d45b/index.js#L561
let decodedUntrustedFilePath: string
try {
// (1) Decode the URL so we have the proper file name
decodedUntrustedFilePath = decodeURIComponent(untrustedFileUrl)
} catch {
return false
}
// (2) Resolve "up paths" to determine real request
const untrustedFilePath = pathResolve(decodedUntrustedFilePath)
// don't allow null bytes anywhere in the file path
if (untrustedFilePath.indexOf('\0') !== -1) {
return false
}
// During development mode, files can be added while the server is running.
// Checks for .next/static, .next/server, static and public.
// Note that in development .next/server is available for error reporting purposes.
// see `packages/next/next-server/server/next-server.ts` for more details.
if (
untrustedFilePath.startsWith(pathJoin(this.distDir, 'static') + sep) ||
untrustedFilePath.startsWith(pathJoin(this.distDir, 'server') + sep) ||
untrustedFilePath.startsWith(pathJoin(this.dir, 'static') + sep) ||
untrustedFilePath.startsWith(pathJoin(this.dir, 'public') + sep)
) {
return true
}
return false
}
}