Basic Java Flight Recorder support

package.json

@@ -39,10 +39,12 @@
     "acorn": "7.2.0",
     "aphrodite": "2.1.0",
     "esbuild": "0.27.0",
+    "esbuild-jest": "0.5.0",
     "eslint": "8.0.0",
     "eslint-plugin-prettier": "5.1.2",
     "eslint-plugin-react-hooks": "4.6.0",
     "jest": "24.3.0",
+    "jfrview": "0.2.0",
     "jsverify": "0.8.3",
     "jszip": "3.1.5",
     "pako": "1.0.6",
@@ -53,17 +55,22 @@
     "ts-jest": "24.3.0",
     "tsx": "4.19.2",
     "typescript": "5.3.3",
-    "typescript-json-schema": "0.42.0",
+    "typescript-json-schema": "0.67.0",
     "uglify-es": "3.2.2",
     "uint8array-json-parser": "0.0.2"
   },
   "jest": {
     "transform": {
-      "^.+\\.tsx?$": "ts-jest"
+      "^.+\\.tsx?$": "ts-jest",
+      "^.+\\.js$": "esbuild-jest"
     },
+    "transformIgnorePatterns": [],
     "setupFilesAfterEnv": [
       "./src/jest-setup.js"
     ],
+    "moduleNameMapper": {
+      "\\jfrview_bg.wasm$": "<rootDir>/src/import/java-flight-record.mock.ts"
+    },
     "testRegex": "\\.test\\.tsx?$",
     "collectCoverageFrom": [
       "**/*.{ts,tsx}",

scripts/esbuild-shared.ts

@@ -26,6 +26,7 @@ export const buildOptions: esbuild.BuildOptions = {
     '.woff2': 'file',
     '.png': 'file',
     '.ico': 'file',
+    '.wasm': 'file',
   },
 }
 

src/global.d.ts

@@ -0,0 +1,8 @@
+declare global {
+  // Mock modern Typescript constructs used in JfrView until we update our Typescript
+  interface SymbolConstructor {
+    readonly dispose: symbol
+  }
+}
+
+export {}

src/import/index.ts

@@ -24,6 +24,7 @@ import {isTraceEventFormatted, importTraceEvents} from './trace-event'
 import {importFromCallgrind} from './callgrind'
 import {importFromPapyrus} from './papyrus'
 import {importFromPMCStatCallGraph} from './pmcstat-callgraph'
+import {importFromJfr, isJfrRecording} from './java-flight-recorder'
 
 export async function importProfileGroupFromText(
   fileName: string,
@@ -127,6 +128,9 @@ async function _importProfileGroup(dataSource: ProfileDataSource): Promise<Profi
   } else if (fileName.endsWith('.pmcstat.graph')) {
     console.log('Importing as pmcstat callgraph format')
     return toGroup(importFromPMCStatCallGraph(contents))
+  } else if (fileName.endsWith('.jfr')) {
+    console.log('Importing as Java Flight Recorder profile')
+    return await importFromJfr(fileName, buffer)
   }
 
   // Second pass: Try to guess what file format it is based on structure
@@ -197,6 +201,11 @@ async function _importProfileGroup(dataSource: ProfileDataSource): Promise<Profi
       return toGroup(importFromPapyrus(contents))
     }
 
+    if (isJfrRecording(buffer)) {
+      console.log('Importing as Java Flight Recorder profile')
+      return importFromJfr(fileName, buffer)
+    }
+
     const fromLinuxPerf = importFromLinuxPerf(contents)
     if (fromLinuxPerf) {
       console.log('Importing from linux perf script output')

src/import/java-flight-record.mock.ts

@@ -0,0 +1,6 @@
+import fs from 'fs'
+
+// We need to load the wasm binary as file
+// This is different from the production case where we load the binary via `fetch`
+const wasm_module = fs.readFileSync('node_modules/jfrview/jfrview_bg.wasm')
+module.exports = wasm_module

src/import/java-flight-recorder.test.ts

@@ -0,0 +1,5 @@
+import {checkProfileSnapshot} from '../lib/test-utils'
+
+test('importFromJfr', async () => {
+  await checkProfileSnapshot('./sample/profiles/java-flight-recorder/heavy.jfr')
+})

src/import/java-flight-recorder.ts

@@ -0,0 +1,46 @@
+import {FrameInfo, Profile, ProfileGroup, StackListProfileBuilder} from '../lib/profile'
+import init, {Frame, interpret_jfr} from 'jfrview'
+// @ts-ignore
+import wasm_data from 'jfrview/jfrview_bg.wasm'
+
+export async function importFromJfr(fileName: string, data: ArrayBuffer): Promise<ProfileGroup> {
+  await init({module_or_path: wasm_data})
+  const withoutNative = create_profile(data, false)
+  const withNative = create_profile(data, true)
+
+  return {
+    indexToView: 0,
+    name: fileName,
+    profiles: [withoutNative, withNative],
+  }
+}
+
+export function isJfrRecording(buffer: ArrayBuffer) {
+  const b = buffer.slice(0, 3)
+  const bytes = new Uint8Array(b)
+  return bytes[0] === 0x46 && bytes[1] === 0x4c && bytes[2] === 0x52
+}
+
+function create_profile(data: ArrayBuffer, includeNative: boolean): Profile {
+  const result = interpret_jfr(new Uint8Array(data), includeNative)
+
+  const builder = new StackListProfileBuilder(result.length)
+  if (includeNative) {
+    builder.setName('With native calls')
+  } else {
+    builder.setName('Without native calls')
+  }
+
+  function to_fi(input: Frame): FrameInfo {
+    return {
+      name: input.name,
+      key: input.name,
+    }
+  }
+
+  for (const sample of result) {
+    builder.appendSampleWithWeight(sample.frames.map(to_fi), 1)
+  }
+
+  return builder.build()
+}

src/jest-setup.js

@@ -54,4 +54,5 @@
   //
   // Let's emulate it being a global API during tests.
   global.TextDecoder = require('util').TextDecoder
+  global.TextEncoder = require('util').TextEncoder
 })()