feat!: bring dev server headers to parity with production (#5490)

BREAKING CHANGE: The `x-powered-by` header in Netlify Dev responses was replaced with a `server` header

package.json

@@ -174,6 +174,7 @@
     "through2-map": "^3.0.0",
     "to-readable-stream": "^2.1.0",
     "toml": "^3.0.0",
+    "ulid": "^2.3.0",
     "unixify": "^1.0.0",
     "update-notifier": "^6.0.0",
     "uuid": "^9.0.0",

src/lib/edge-functions/headers.mjs

@@ -3,7 +3,6 @@ const headers = {
   Functions: 'x-nf-edge-functions',
   Geo: 'x-nf-geo',
   Passthrough: 'x-nf-passthrough',
-  RequestID: 'X-NF-Request-ID',
   IP: 'x-nf-client-connection-ip',
   Site: 'X-NF-Site-Info',
   DebugLogging: 'x-nf-debug-logging',

src/lib/edge-functions/proxy.mjs

@@ -4,7 +4,6 @@ import { relative } from 'path'
 import { cwd, env } from 'process'
 
 import getAvailablePort from 'get-port'
-import { v4 as generateUUID } from 'uuid'
 
 import { NETLIFYDEVERR, NETLIFYDEVWARN, chalk, error as printError, log } from '../../utils/command-helpers.mjs'
 import { getGeoLocation } from '../geo-location.mjs'
@@ -133,7 +132,6 @@ export const initializeProxy = async ({
       [headers.Functions]: functionNames.join(','),
       [headers.ForwardedHost]: `localhost:${passthroughPort}`,
       [headers.Passthrough]: 'passthrough',
-      [headers.RequestID]: generateUUID(),
       [headers.IP]: LOCAL_HOST,
     }
 

src/utils/headers.mjs

@@ -45,3 +45,5 @@ const handleHeadersErrors = function (errors) {
 const getErrorMessage = function ({ message }) {
   return message
 }
+
+export const NFRequestID = 'x-nf-request-id'

src/utils/proxy.mjs

@@ -31,7 +31,8 @@ import renderErrorTemplate from '../lib/render-error-template.mjs'
 
 import { NETLIFYDEVLOG, NETLIFYDEVWARN, log, chalk } from './command-helpers.mjs'
 import createStreamPromise from './create-stream-promise.mjs'
-import { headersForPath, parseHeaders } from './headers.mjs'
+import { headersForPath, parseHeaders, NFRequestID } from './headers.mjs'
+import { generateRequestID } from './request-id.mjs'
 import { createRewriter, onChanges } from './rules-proxy.mjs'
 import { signRedirect } from './sign-redirect.mjs'
 
@@ -369,6 +370,11 @@ const initializeProxy = async function ({ configPath, distDir, env, host, port,
     res.end(message)
   })
   proxy.on('proxyReq', (proxyReq, req) => {
+    const requestID = generateRequestID()
+
+    proxyReq.setHeader(NFRequestID, requestID)
+    req.headers[NFRequestID] = requestID
+
     if (isEdgeFunctionsRequest(req)) {
       handleProxyRequest(req, proxyReq)
     }
@@ -383,6 +389,14 @@ const initializeProxy = async function ({ configPath, distDir, env, host, port,
     }
   })
   proxy.on('proxyRes', (proxyRes, req, res) => {
+    res.setHeader('server', 'Netlify')
+
+    const requestID = req.headers[NFRequestID]
+
+    if (requestID) {
+      res.setHeader(NFRequestID, requestID)
+    }
+
     if (proxyRes.statusCode === 404 || proxyRes.statusCode === 403) {
       if (req.alternativePaths && req.alternativePaths.length !== 0) {
         req.url = req.alternativePaths.shift()

src/utils/request-id.mjs

@@ -0,0 +1,4 @@
+// @ts-check
+import { ulid } from 'ulid'
+
+export const generateRequestID = () => ulid()

src/utils/static-server.mjs

@@ -21,7 +21,8 @@ export const startStaticServer = async ({ settings }) => {
   })
 
   server.addHook('onRequest', (req, reply, done) => {
-    reply.header('X-Powered-by', 'netlify-dev')
+    reply.header('age', '0')
+    reply.header('cache-control', 'public, max-age=0, must-revalidate')
     const validMethods = ['GET', 'HEAD']
     if (!validMethods.includes(req.method)) {
       reply.code(405).send('Method Not Allowed')

tests/integration/100.command.dev.test.cjs

@@ -198,7 +198,7 @@ test('Serves an Edge Function that terminates a response', async (t) => {
         },
       ])
       .withEdgeFunction({
-        handler: () => new Response('Hello world'),
+        handler: (req) => new Response(req.headers.get('x-nf-request-id')),
         name: 'hello',
       })
 
@@ -208,7 +208,8 @@ test('Serves an Edge Function that terminates a response', async (t) => {
       const response = await got(`${server.url}/edge-function`)
 
       t.is(response.statusCode, 200)
-      t.is(response.body, 'Hello world')
+      t.is(response.body.length, 26)
+      t.is(response.body, response.headers['x-nf-request-id'])
     })
   })
 })

tests/integration/130.eleventy.test.cjs

@@ -56,9 +56,10 @@ test('force rewrite', async (t) => {
 test('functions rewrite echo without body', async (t) => {
   const { host, port, url } = t.context.server
   const response = await got(`${url}/api/echo?ding=dong`).json()
+  const { 'x-nf-request-id': requestID, ...headers } = response.headers
 
   t.is(response.body, undefined)
-  t.deepEqual(response.headers, {
+  t.deepEqual(headers, {
     accept: 'application/json',
     'accept-encoding': 'gzip, deflate, br',
     'client-ip': clientIP,
@@ -67,6 +68,7 @@ test('functions rewrite echo without body', async (t) => {
     'user-agent': 'got (https://github.com/sindresorhus/got)',
     'x-forwarded-for': originalIP,
   })
+  t.is(requestID.length, 26)
   t.is(response.httpMethod, 'GET')
   t.is(response.isBase64Encoded, true)
   t.is(response.path, '/api/echo')
@@ -83,9 +85,10 @@ test('functions rewrite echo with body', async (t) => {
       body: 'some=thing',
     })
     .json()
+  const { 'x-nf-request-id': requestID, ...headers } = response.headers
 
   t.is(response.body, 'some=thing')
-  t.deepEqual(response.headers, {
+  t.deepEqual(headers, {
     accept: 'application/json',
     'accept-encoding': 'gzip, deflate, br',
     'client-ip': clientIP,
@@ -96,6 +99,7 @@ test('functions rewrite echo with body', async (t) => {
     'user-agent': 'got (https://github.com/sindresorhus/got)',
     'x-forwarded-for': originalIP,
   })
+  t.is(requestID.length, 26)
   t.is(response.httpMethod, 'POST')
   t.is(response.isBase64Encoded, false)
   t.is(response.path, '/api/echo')
@@ -105,8 +109,9 @@ test('functions rewrite echo with body', async (t) => {
 test('functions echo with multiple query params', async (t) => {
   const { host, port, url } = t.context.server
   const response = await got(`${url}/.netlify/functions/echo?category=a&category=b`).json()
+  const { 'x-nf-request-id': requestID, ...headers } = response.headers
 
-  t.deepEqual(response.headers, {
+  t.deepEqual(headers, {
     accept: 'application/json',
     'accept-encoding': 'gzip, deflate, br',
     'client-ip': clientIP,
@@ -115,6 +120,7 @@ test('functions echo with multiple query params', async (t) => {
     'user-agent': 'got (https://github.com/sindresorhus/got)',
     'x-forwarded-for': originalIP,
   })
+  t.is(requestID.length, 26)
   t.is(response.httpMethod, 'GET')
   t.is(response.isBase64Encoded, true)
   t.is(response.path, '/.netlify/functions/echo')