ref: Restore node 6 support due to yarn engine checks, add performance.now fallback (#2460)

Author: kamilogorek

.travis.yml

@@ -29,6 +29,9 @@ jobs:
       name: '@sentry/packages - build + lint + test + codecov + danger [node v12]'
       node_js: '12'
       script: scripts/danger.sh
+    - name: '@sentry/packages - build and test [node v6]'
+      node_js: '6'
+      script: scripts/test.sh
     - name: '@sentry/packages - build and test [node v8]'
       node_js: '8'
       script: scripts/test.sh

packages/apm/src/span.ts

@@ -13,18 +13,24 @@ import {
   uuid4,
 } from '@sentry/utils';
 
+const INITIAL_TIME = Date.now();
+
+const performanceFallback: Pick<Performance, 'now'> = {
+  now(): number {
+    return INITIAL_TIME - Date.now();
+  },
+};
+
 const crossPlatformPerformance: Pick<Performance, 'now'> = (() => {
   if (isNodeEnv()) {
-    const { performance } = dynamicRequire(module, 'perf_hooks') as { performance: Performance };
-    return performance;
-  }
-  return (
-    getGlobalObject<Window>().performance || {
-      now(): number {
-        return Date.now();
-      },
+    try {
+      const perfHooks = dynamicRequire(module, 'perf_hooks') as { performance: Performance };
+      return perfHooks.performance;
+    } catch (_) {
+      return performanceFallback;
     }
-  );
+  }
+  return getGlobalObject<Window>().performance || performanceFallback;
 })();
 
 // TODO: Should this be exported?

packages/node/package.json

@@ -7,7 +7,7 @@
   "author": "Sentry",
   "license": "BSD-3-Clause",
   "engines": {
-    "node": ">=8"
+    "node": ">=6"
   },
   "main": "dist/index.js",
   "module": "esm/index.js",