Fix DecodeError from invalid URI causes 500 with middleware vs 400 wi…

…thout (#36993)

* Excluded `DecodeError` error from runMiddleware function

* Fix merge error/check and add test

Co-authored-by: JJ Kasper <jj@jjsweb.site>

packages/next/server/dev/next-dev-server.ts

@@ -632,6 +632,9 @@ export default class DevServer extends Server {
  )
  return result
  } catch (error) {
+ if (error instanceof DecodeError) {
+ throw error
+ }
  this.logErrorWithOriginalStack(error, undefined, 'edge-server')
 
  const preflight =

packages/next/server/next-server.ts

@@ -2,7 +2,7 @@ import './node-polyfill-fetch'
 import './node-polyfill-web-streams'
 
 import type { Route } from './router'
-import type { CacheFs } from '../shared/lib/utils'
+import { CacheFs, DecodeError, execOnce } from '../shared/lib/utils'
 import type { MiddlewareManifest } from '../build/webpack/plugins/middleware-plugin'
 import type RenderResult from './render-result'
 import type { FetchEventResult } from './web/types'
@@ -18,8 +18,6 @@ import type { Params } from '../shared/lib/router/utils/route-matcher'
 import fs from 'fs'
 import { join, relative, resolve, sep } from 'path'
 import { IncomingMessage, ServerResponse } from 'http'
-
-import { execOnce } from '../shared/lib/utils'
 import { addRequestMeta, getRequestMeta } from './request-meta'
 
 import {
@@ -1252,6 +1250,12 @@ export default class NextNodeServer extends BaseServer {
  return { finished: true }
  }
 
+ if (err instanceof DecodeError) {
+ res.statusCode = 400
+ this.renderError(err, req, res, parsed.pathname || '')
+ return { finished: true }
+ }
+
  const error = getProperError(err)
  console.error(error)
  res.statusCode = 500

test/integration/middleware-general/test/index.test.js

@@ -27,6 +27,7 @@ describe('Middleware Runtime', () => {
  describe('dev mode', () => {
  afterAll(() => killApp(context.app))
  beforeAll(async () => {
+ context.dev = true
  context.appPort = await findPort()
  context.app = await launchApp(context.appDir, context.appPort, {
  env: {
@@ -87,6 +88,7 @@ describe('Middleware Runtime', () => {
  stderr: build.stderr,
  stdout: build.stdout,
  }
+ context.dev = false
 
  context.appPort = await findPort()
  context.app = await nextStart(context.appDir, context.appPort, {
@@ -133,6 +135,15 @@ describe('Middleware Runtime', () => {
 })
 
 function tests(context, locale = '') {
+ it('should respond with 400 on decode failure', async () => {
+ const res = await fetchViaHTTP(context.appPort, `${locale}/%2`)
+ expect(res.status).toBe(400)
+
+ if (!context.dev) {
+ expect(await res.text()).toContain('Bad Request')
+ }
+ })
+
  it('should set fetch user agent correctly', async () => {
  const res = await fetchViaHTTP(
  context.appPort,