Disallow both Fastly AND the browser from caching HTML pages (#17641)

JamesMGreene · web-flow · commit 8f133cbf5464 · 2021-02-02T21:37:41.000Z
diff --git a/middleware/index.js b/middleware/index.js
@@ -38,7 +38,6 @@ module.exports = function (app) {
 
   // *** Headers ***
   app.use(require('compression')())
-  app.use(require('./set-fastly-cache-headers'))
   app.use(require('./disable-caching-on-safari'))
 
   // *** Config and context for redirects ***
@@ -93,6 +92,9 @@ module.exports = function (app) {
   app.use(instrument('./featured-links'))
   app.use(instrument('./learning-track'))
 
+  // *** Headers for pages only ***
+  app.use(require('./set-fastly-cache-headers'))
+
   // *** Rendering, must go last ***
   app.get('/*', asyncMiddleware(instrument('./render-page')))
   app.use(require('./handle-errors'))
diff --git a/middleware/set-fastly-cache-headers.js b/middleware/set-fastly-cache-headers.js
@@ -1,12 +1,12 @@
 const FASTLY_TTL = process.env.FASTLY_TTL || String(60 * 60 * 24) // 24 hours
 const STALE_TTL = String(60 * 10) // 10 minutes
 
-const BYPASS_FASTLY = process.env.TEST_BYPASS_FASTLY === 'true'
-const BYPASS_PRODUCTS = /^\/([a-z]{2})\/([a-z0-9._-]+@[a-z0-9._-]+\/)?github(\/.*|$)/i
-
 module.exports = (req, res, next) => {
-  // Test bypassing Fastly for all pages inside of the Discussions product
-  if (BYPASS_FASTLY && !BYPASS_PRODUCTS.test(req.originalUrl)) {
+  const BYPASS_FASTLY = process.env.TEST_BYPASS_FASTLY === 'true'
+
+  // Bypass Fastly caching for all rendered pages
+  if (BYPASS_FASTLY) {
+    // Disallow both Fastly AND the browser from caching HTML pages
     res.set({
       'surrogate-control': 'private, no-store',
       'cache-control': 'private, no-store'
diff --git a/tests/rendering/server.js b/tests/rendering/server.js
@@ -66,6 +66,15 @@ describe('server', () => {
     expect(res.headers['surrogate-key']).toBe('all-the-things')
   })
 
+  test('sets Fastly cache control headers to bypass if enabled', async () => {
+    process.env.TEST_BYPASS_FASTLY = 'true'
+
+    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).not.toHaveProperty('surrogate-key')
+  })
+
   test('does not render duplicate <html> or <body> tags', async () => {
     const $ = await getDOM('/en')
     expect($('html').length).toBe(1)
