Prepare render-page for re-enabling HTML caching (#29473)

heiskr · web-flow · commit a16aeac93694 · 2022-07-29T19:49:36.000Z
* Prepare render-page for re-enabling HTML caching

* Prepare render-page for re-enabling HTML caching

* Prepare render-page for re-enabling HTML caching

* Update healthz.js

* Pre calculate cache control directives

* Update render-page.js
diff --git a/middleware/cache-control.js b/middleware/cache-control.js
@@ -15,17 +15,18 @@
 //    noControlYear(res)
 //    res.send(body)
 //
+// Max age is in seconds
 export function cacheControlFactory(maxAge = 60 * 60, { public_ = true, immutable = false } = {}) {
+  const directives = [
+    maxAge && public_ && 'public',
+    maxAge && `max-age=${maxAge}`,
+    maxAge && immutable && 'immutable',
+    !maxAge && 'private',
+    !maxAge && 'no-store',
+  ]
+    .filter(Boolean)
+    .join(', ')
   return (res) => {
-    const directives = []
-    if (maxAge) {
-      if (public_) directives.push('public')
-      directives.push(`max-age=${maxAge}`)
-      if (immutable) directives.push('immutable')
-    } else {
-      directives.push('private')
-      directives.push('no-store')
-    }
-    res.set('cache-control', directives.join(', '))
+    res.set('cache-control', directives)
   }
 }
diff --git a/middleware/healthz.js b/middleware/healthz.js
@@ -1,18 +1,18 @@
 import express from 'express'
+import { cacheControlFactory } from './cache-control.js'
 
 const router = express.Router()
 
+const noCacheControl = cacheControlFactory(0)
+
 /**
  * Returns the healthiness of the service.
  * This may be used by azure app service (forthcoming) to determine whether this
  * instance remains in the pool to handle requests
  * For example: if we have a failing database connection we may return a 500 status here.
  */
 router.get('/', function healthz(req, res, next) {
-  res.set({
-    'surrogate-control': 'private, no-store',
-    'cache-control': 'private, no-store',
-  })
+  noCacheControl(res)
 
   res.sendStatus(200)
 })
diff --git a/middleware/index.js b/middleware/index.js
@@ -14,7 +14,6 @@ import cookieParser from './cookie-parser.js'
 import csrf from './csrf.js'
 import handleCsrfErrors from './handle-csrf-errors.js'
 import { setDefaultFastlySurrogateKey } from './set-fastly-surrogate-key.js'
-import setFastlyCacheHeaders from './set-fastly-cache-headers.js'
 import reqUtils from './req-utils.js'
 import recordRedirect from './record-redirect.js'
 import handleErrors from './handle-errors.js'
@@ -303,9 +302,6 @@ export default function (app) {
     app.use('/fastly-cache-test', fastlyCacheTest)
   }
 
-  // *** Headers for pages only ***
-  app.use(setFastlyCacheHeaders)
-
   // handle serving NextJS bundled code (/_next/*)
   app.use(instrument(next, './next'))
 
diff --git a/middleware/render-page.js b/middleware/render-page.js
@@ -7,6 +7,13 @@ import statsd from '../lib/statsd.js'
 import { allVersions } from '../lib/all-versions.js'
 import { isConnectionDropped } from './halt-on-dropped-connection.js'
 import { nextApp, nextHandleRequest } from './next.js'
+import { cacheControlFactory } from './cache-control.js'
+
+const noCacheControl = cacheControlFactory(0)
+
+const htmlCacheControl = cacheControlFactory(0)
+// We'll start with no cache, the increase to one minute (60),
+// then five minutes (60 * 5), finally ten minutes (60 * 10)
 
 async function buildRenderedPage(req) {
   const { context } = req
@@ -54,6 +61,7 @@ export default async function renderPage(req, res, next) {
 
   // render a 404 page
   if (!page) {
+    noCacheControl(res)
     if (process.env.NODE_ENV !== 'test' && context.redirectNotFound) {
       console.error(
         `\nTried to redirect to ${context.redirectNotFound}, but that page was not found.\n`
@@ -64,9 +72,12 @@ export default async function renderPage(req, res, next) {
 
   // Just finish fast without all the details like Content-Length
   if (req.method === 'HEAD') {
+    noCacheControl(res)
     return res.status(200).send('')
   }
 
+  htmlCacheControl(res)
+
   // Updating the Last-Modified header for substantive changes on a page for engineering
   // Docs Engineering Issue #945
   if (page.effectiveDate) {
diff --git a/middleware/set-fastly-cache-headers.js b/middleware/set-fastly-cache-headers.js
diff --git a/tests/rendering/server.js b/tests/rendering/server.js
@@ -132,7 +132,6 @@ describe('server', () => {
   test('sets Fastly cache control headers to bypass pages', async () => {
     const res = await get('/en')
     expect(res.headers['cache-control']).toBe('private, no-store')
-    expect(res.headers['surrogate-control']).toBe('private, no-store')
     expect(res.headers['surrogate-key']).toBe(SURROGATE_ENUMS.DEFAULT)
   })
 
