Merge pull request #13024 from github/repo-sync

repo sync

middleware/render-page.js

@@ -5,6 +5,8 @@ import Page from '../lib/page.js'
 import { isConnectionDropped } from './halt-on-dropped-connection.js'
 import { nextApp, nextHandleRequest } from './next.js'
 
+const pageCache = new Map()
+
 export default async function renderPage(req, res, next) {
   if (req.path.startsWith('/storybook')) {
     return nextHandleRequest(req, res)
@@ -29,6 +31,45 @@ export default async function renderPage(req, res, next) {
   // Is the request for JSON debugging info?
   const isRequestingJsonForDebugging = 'json' in req.query && process.env.NODE_ENV !== 'production'
 
+  // ****** temporary caching measure for holiday spam prevention *********
+
+  const isApiPage =
+    req.context.currentPathWithoutLanguage.includes('rest/reference') ||
+    req.context.currentPathWithoutLanguage.includes('graphql/reference')
+
+  // Serve from the cache if possible
+  const isCacheable =
+    // Skip for CI
+    !process.env.CI &&
+    // Skip for tests
+    process.env.NODE_ENV !== 'test' &&
+    // Skip for HTTP methods other than GET
+    req.method === 'GET' &&
+    // Skip for JSON debugging info requests
+    !isRequestingJsonForDebugging &&
+    // Only API pages
+    isApiPage
+
+  // don't cache query strings
+  const originalUrl = req.originalUrl.split('?')[0]
+
+  if (isCacheable) {
+    // Stop processing if the connection was already dropped
+    if (isConnectionDropped(req, res)) return
+
+    const cachedHtml = pageCache.get(originalUrl)
+    if (cachedHtml) {
+      // Stop processing if the connection was already dropped
+      if (isConnectionDropped(req, res)) return
+
+      console.log(`Serving from cached version of ${originalUrl}`)
+      // statsd.increment('page.sent_from_cache')
+      return res.send(cachedHtml)
+    }
+  }
+
+  // ****** [end] temporary caching measure for holiday spam prevention *********
+
   // add page context
   const context = Object.assign({}, req.context, { page })
 
@@ -104,5 +145,12 @@ export default async function renderPage(req, res, next) {
   // Hand rendering over to NextJS
   req.context.renderedPage = context.renderedPage
   req.context.miniTocItems = context.miniTocItems
+
+  // ****** temporary caching measure for holiday spam prevention *********
+  if (isCacheable) {
+    pageCache.set(originalUrl, req.context.renderedPage)
+  }
+  // ****** [end] temporary caching measure for holiday spam prevention *********
+
   return nextHandleRequest(req, res)
 }