perf: improve getResolveErrorBodyCallback (nodejs#2940)

Author: Uzlopak

benchmarks/api/util.mjs

@@ -0,0 +1,37 @@
+import { bench, group, run } from 'mitata'
+import { isContentTypeText, isContentTypeApplicationJson } from '../../lib/api/util.js'
+
+const html = 'text/html'
+const json = 'application/json; charset=UTF-8'
+
+group('isContentTypeText', () => {
+  bench(`isContentTypeText('${html}')`, () => {
+    return isContentTypeText(html)
+  })
+  bench(`isContentTypeText('${json}')`, () => {
+    return isContentTypeText(json)
+  })
+  bench('html.startsWith(\'text/\')', () => {
+    return html.startsWith('text/')
+  })
+  bench('json.startsWith(\'text/\')', () => {
+    return json.startsWith('text/')
+  })
+})
+
+group('isContentTypeApplicationJson', () => {
+  bench(`isContentTypeApplicationJson('${html}')`, () => {
+    return isContentTypeApplicationJson(html)
+  })
+  bench(`isContentTypeApplicationJson('${json}')`, () => {
+    return isContentTypeApplicationJson(json)
+  })
+  bench('html.startsWith(\'application/json\')', () => {
+    return html.startsWith('application/json')
+  })
+  bench('json.startsWith(\'application/json\')', () => {
+    return json.startsWith('application/json')
+  })
+})
+
+await run()

lib/api/util.js

@@ -21,28 +21,66 @@ async function getResolveErrorBodyCallback ({ callback, body, contentType, statu
     }
   }
 
+  const message = `Response status code ${statusCode}${statusMessage ? `: ${statusMessage}` : ''}`
+
   if (statusCode === 204 || !contentType || !chunks) {
-    process.nextTick(callback, new ResponseStatusCodeError(`Response status code ${statusCode}${statusMessage ? `: ${statusMessage}` : ''}`, statusCode, headers))
+    queueMicrotask(() => callback(new ResponseStatusCodeError(message, statusCode, headers)))
     return
   }
 
-  try {
-    if (contentType.startsWith('application/json')) {
-      const payload = JSON.parse(chunksDecode(chunks, length))
-      process.nextTick(callback, new ResponseStatusCodeError(`Response status code ${statusCode}${statusMessage ? `: ${statusMessage}` : ''}`, statusCode, headers, payload))
-      return
-    }
+  const stackTraceLimit = Error.stackTraceLimit
+  Error.stackTraceLimit = 0
+  let payload
 
-    if (contentType.startsWith('text/')) {
-      const payload = chunksDecode(chunks, length)
-      process.nextTick(callback, new ResponseStatusCodeError(`Response status code ${statusCode}${statusMessage ? `: ${statusMessage}` : ''}`, statusCode, headers, payload))
-      return
+  try {
+    if (isContentTypeApplicationJson(contentType)) {
+      payload = JSON.parse(chunksDecode(chunks, length))
+    } else if (isContentTypeText(contentType)) {
+      payload = chunksDecode(chunks, length)
     }
-  } catch (err) {
-    // Process in a fallback if error
+  } catch {
+    // process in a callback to avoid throwing in the microtask queue
+  } finally {
+    Error.stackTraceLimit = stackTraceLimit
   }
+  queueMicrotask(() => callback(new ResponseStatusCodeError(message, statusCode, headers, payload)))
+}
+
+const isContentTypeApplicationJson = (contentType) => {
+  return (
+    contentType.length > 15 &&
+    contentType[11] === '/' &&
+    contentType[0] === 'a' &&
+    contentType[1] === 'p' &&
+    contentType[2] === 'p' &&
+    contentType[3] === 'l' &&
+    contentType[4] === 'i' &&
+    contentType[5] === 'c' &&
+    contentType[6] === 'a' &&
+    contentType[7] === 't' &&
+    contentType[8] === 'i' &&
+    contentType[9] === 'o' &&
+    contentType[10] === 'n' &&
+    contentType[12] === 'j' &&
+    contentType[13] === 's' &&
+    contentType[14] === 'o' &&
+    contentType[15] === 'n'
+  )
+}
 
-  process.nextTick(callback, new ResponseStatusCodeError(`Response status code ${statusCode}${statusMessage ? `: ${statusMessage}` : ''}`, statusCode, headers))
+const isContentTypeText = (contentType) => {
+  return (
+    contentType.length > 4 &&
+    contentType[4] === '/' &&
+    contentType[0] === 't' &&
+    contentType[1] === 'e' &&
+    contentType[2] === 'x' &&
+    contentType[3] === 't'
+  )
 }
 
-module.exports = { getResolveErrorBodyCallback }
+module.exports = {
+  getResolveErrorBodyCallback,
+  isContentTypeApplicationJson,
+  isContentTypeText
+}