Refactor code (vercel#64429)

shuding · web-flow · commit 3fb72dc6580e · 2024-06-23T20:16:13.000Z
Small code refactoring to make the server do fewer work.

Closes NEXT-3096
diff --git a/packages/next/src/server/client-component-renderer-logger.ts b/packages/next/src/server/client-component-renderer-logger.ts
@@ -10,11 +10,12 @@ export function wrapClientComponentLoader(ComponentMod: any) {
 
   return {
     require: (...args: any[]) => {
+      const startTime = performance.now()
+
       if (clientComponentLoadStart === 0) {
-        clientComponentLoadStart = performance.now()
+        clientComponentLoadStart = startTime
       }
 
-      const startTime = performance.now()
       try {
         clientComponentLoadCount += 1
         return ComponentMod.__next_app__.require(...args)
diff --git a/packages/next/src/server/stream-utils/node-web-streams-helper.ts b/packages/next/src/server/stream-utils/node-web-streams-helper.ts
@@ -130,6 +130,7 @@ export function createBufferedTransformStream(): TransformStream<
       try {
         const chunk = new Uint8Array(bufferByteLength)
         let copiedBytes = 0
+
         for (let i = 0; i < bufferedChunks.length; i++) {
           const bufferedChunk = bufferedChunks[i]
           chunk.set(bufferedChunk, copiedBytes)
@@ -376,31 +377,29 @@ function createMergedTransformStream(
   })
 }
 
+const CLOSE_TAG = '</body></html>'
+
 /**
  * This transform stream moves the suffix to the end of the stream, so results
  * like `</body></html><script>...</script>` will be transformed to
  * `<script>...</script></body></html>`.
  */
-function createMoveSuffixStream(
-  suffix: string
-): TransformStream<Uint8Array, Uint8Array> {
+function createMoveSuffixStream(): TransformStream<Uint8Array, Uint8Array> {
   let foundSuffix = false
 
-  const encodedSuffix = encoder.encode(suffix)
-
   return new TransformStream({
     transform(chunk, controller) {
       if (foundSuffix) {
         return controller.enqueue(chunk)
       }
 
-      const index = indexOfUint8Array(chunk, encodedSuffix)
+      const index = indexOfUint8Array(chunk, ENCODED_TAGS.CLOSED.BODY_AND_HTML)
       if (index > -1) {
         foundSuffix = true
 
         // If the whole chunk is the suffix, then don't write anything, it will
         // be written in the flush.
-        if (chunk.length === suffix.length) {
+        if (chunk.length === ENCODED_TAGS.CLOSED.BODY_AND_HTML.length) {
           return
         }
 
@@ -410,9 +409,11 @@ function createMoveSuffixStream(
 
         // In the case where the suffix is in the middle of the chunk, we need
         // to split the chunk into two parts.
-        if (chunk.length > suffix.length + index) {
+        if (chunk.length > ENCODED_TAGS.CLOSED.BODY_AND_HTML.length + index) {
           // Write out the part after the suffix.
-          const after = chunk.slice(index + suffix.length)
+          const after = chunk.slice(
+            index + ENCODED_TAGS.CLOSED.BODY_AND_HTML.length
+          )
           controller.enqueue(after)
         }
       } else {
@@ -422,7 +423,7 @@ function createMoveSuffixStream(
     flush(controller) {
       // Even if we didn't find the suffix, the HTML is not valid if we don't
       // add it, so insert it at the end.
-      controller.enqueue(encodedSuffix)
+      controller.enqueue(ENCODED_TAGS.CLOSED.BODY_AND_HTML)
     },
   })
 }
@@ -542,10 +543,8 @@ export async function continueFizzStream(
     validateRootLayout,
   }: ContinueStreamOptions
 ): Promise<ReadableStream<Uint8Array>> {
-  const closeTag = '</body></html>'
-
   // Suffix itself might contain close tags at the end, so we need to split it.
-  const suffixUnclosed = suffix ? suffix.split(closeTag, 1)[0] : null
+  const suffixUnclosed = suffix ? suffix.split(CLOSE_TAG, 1)[0] : null
 
   // If we're generating static HTML and there's an `allReady` promise on the
   // stream, we need to wait for it to resolve before continuing.
@@ -574,7 +573,7 @@ export async function continueFizzStream(
     validateRootLayout ? createRootLayoutValidatorStream() : null,
 
     // Close tags should always be deferred to the end
-    createMoveSuffixStream(closeTag),
+    createMoveSuffixStream(),
 
     // Special head insertions
     // TODO-APP: Insert server side html to end of head in app layout rendering, to avoid
@@ -612,8 +611,6 @@ export async function continueStaticPrerender(
   prerenderStream: ReadableStream<Uint8Array>,
   { inlinedDataStream, getServerInsertedHTML }: ContinueStaticPrerenderOptions
 ) {
-  const closeTag = '</body></html>'
-
   return (
     prerenderStream
       // Buffer everything to avoid flushing too frequently
@@ -623,7 +620,7 @@ export async function continueStaticPrerender(
       // Insert the inlined data (Flight data, form state, etc.) stream into the HTML
       .pipeThrough(createMergedTransformStream(inlinedDataStream))
       // Close tags should always be deferred to the end
-      .pipeThrough(createMoveSuffixStream(closeTag))
+      .pipeThrough(createMoveSuffixStream())
   )
 }
 
@@ -636,8 +633,6 @@ export async function continueDynamicHTMLResume(
   renderStream: ReadableStream<Uint8Array>,
   { inlinedDataStream, getServerInsertedHTML }: ContinueResumeOptions
 ) {
-  const closeTag = '</body></html>'
-
   return (
     renderStream
       // Buffer everything to avoid flushing too frequently
@@ -647,7 +642,7 @@ export async function continueDynamicHTMLResume(
       // Insert the inlined data (Flight data, form state, etc.) stream into the HTML
       .pipeThrough(createMergedTransformStream(inlinedDataStream))
       // Close tags should always be deferred to the end
-      .pipeThrough(createMoveSuffixStream(closeTag))
+      .pipeThrough(createMoveSuffixStream())
   )
 }
 
@@ -659,13 +654,11 @@ export async function continueDynamicDataResume(
   renderStream: ReadableStream<Uint8Array>,
   { inlinedDataStream }: ContinueDynamicDataResumeOptions
 ) {
-  const closeTag = '</body></html>'
-
   return (
     renderStream
       // Insert the inlined data (Flight data, form state, etc.) stream into the HTML
       .pipeThrough(createMergedTransformStream(inlinedDataStream))
       // Close tags should always be deferred to the end
-      .pipeThrough(createMoveSuffixStream(closeTag))
+      .pipeThrough(createMoveSuffixStream())
   )
 }
diff --git a/packages/next/src/shared/lib/router/utils/is-bot.ts b/packages/next/src/shared/lib/router/utils/is-bot.ts
@@ -1,5 +1,6 @@
+const BOT_UA_RE =
+  /Googlebot|Mediapartners-Google|AdsBot-Google|googleweblight|Storebot-Google|Google-PageRenderer|Bingbot|BingPreview|Slurp|DuckDuckBot|baiduspider|yandex|sogou|LinkedInBot|bitlybot|tumblr|vkShare|quora link preview|facebookexternalhit|facebookcatalog|Twitterbot|applebot|redditbot|Slackbot|Discordbot|WhatsApp|SkypeUriPreview|ia_archiver/i
+
 export function isBot(userAgent: string): boolean {
-  return /Googlebot|Mediapartners-Google|AdsBot-Google|googleweblight|Storebot-Google|Google-PageRenderer|Bingbot|BingPreview|Slurp|DuckDuckBot|baiduspider|yandex|sogou|LinkedInBot|bitlybot|tumblr|vkShare|quora link preview|facebookexternalhit|facebookcatalog|Twitterbot|applebot|redditbot|Slackbot|Discordbot|WhatsApp|SkypeUriPreview|ia_archiver/i.test(
-    userAgent
-  )
+  return BOT_UA_RE.test(userAgent)
 }
