inspector: add a "NodeTracing" domain support

This change adds a new inspector domain for receiving Node tracing
data.
  1. Node.js now can extend Inspector protocol with new domains with
     the API defined in the src/inspector/node_protocol.pdl.
  2. Plumbing code will be generated at the build time. /json/protocol
     HTTP endpoint returns both V8 and Node.js inspector protocol.
  3. "NodeTracing" domain was introduced. It is based on the Chrome
     "Tracing" domain.

PR-URL: https://github.com/nodejs/node/pull/20608
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Ali Ijaz Sheikh <ofrobots@google.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>

1 files changed, 70 insertions, 0 deletions

diff --git a/test/parallel/test-inspector-tracing-domain.js b/test/parallel/test-inspector-tracing-domain.js
new file mode 100644
index 0000000000..61a853a265
--- /dev/null
+++ b/test/parallel/test-inspector-tracing-domain.js
@@ -0,0 +1,70 @@
+'use strict';
+
+const common = require('../common');
+
+common.skipIfInspectorDisabled();
+
+const assert = require('assert');
+const { Session } = require('inspector');
+
+const session = new Session();
+
+function compareIgnoringOrder(array1, array2) {
+  const set = new Set(array1);
+  const test = set.size === array2.length && array2.every((el) => set.has(el));
+  assert.ok(test, `[${array1}] differs from [${array2}]`);
+}
+
+function post(message, data) {
+  return new Promise((resolve, reject) => {
+    session.post(message, data, (err, result) => {
+      if (err)
+        reject(new Error(JSON.stringify(err)));
+      else
+        resolve(result);
+    });
+  });
+}
+
+function generateTrace() {
+  return new Promise((resolve) => setTimeout(() => {
+    for (let i = 0; i << 1000000; i++) {
+      'test' + i;
+    }
+    resolve();
+  }, 1));
+}
+
+async function test() {
+  // This interval ensures Node does not terminate till the test is finished.
+  // Inspector session does not keep the node process running (e.g. it does not
+  // have async handles on the main event loop). It is debatable whether this
+  // should be considered a bug, and there are no plans to fix it atm.
+  const interval = setInterval(() => {}, 5000);
+  session.connect();
+  let traceNotification = null;
+  let tracingComplete = false;
+  session.on('NodeTracing.dataCollected', (n) => traceNotification = n);
+  session.on('NodeTracing.tracingComplete', () => tracingComplete = true);
+  const { categories } = await post('NodeTracing.getCategories');
+  compareIgnoringOrder(['node', 'node.async', 'node.bootstrap', 'node.fs.sync',
+                        'node.perf', 'node.perf.usertiming',
+                        'node.perf.timerify', 'v8'],
+                       categories);
+
+  const traceConfig = { includedCategories: ['node'] };
+  await post('NodeTracing.start', { traceConfig });
+
+  for (let i = 0; i < 5; i++)
+    await generateTrace();
+  JSON.stringify(await post('NodeTracing.stop', { traceConfig }));
+  session.disconnect();
+  assert(traceNotification.data.value.length > 0);
+  assert(tracingComplete);
+  clearInterval(interval);
+  console.log('Success');
+}
+
+common.crashOnUnhandledRejection();
+
+test();