From c95acdc655b658739459318a26d3930a69aed1b7 Mon Sep 17 00:00:00 2001
From: James Sumners <jsumners@newrelic.com>
Date: Thu, 23 Jan 2025 07:54:50 -0500
Subject: [PATCH] fix time calculations

---
 lib/health-reporter.js                | 11 +++++++++--
 test/unit/lib/health-reporter.test.js | 22 +++++++++++-----------
 2 files changed, 20 insertions(+), 13 deletions(-)

diff --git a/lib/health-reporter.js b/lib/health-reporter.js
index f390982aaa..67974c7ed3 100644
--- a/lib/health-reporter.js
+++ b/lib/health-reporter.js
@@ -28,8 +28,15 @@ const VALID_CODES = new Map([
   ['NR-APM-300', 'An unexpected error occurred.']
 ])
 
+function getTime() {
+  // `process.hrtime.bigint` does not return a value relative to the epoch.
+  // So we have to perform this lossy calculation because the spec is
+  // insisting on nanoseconds.
+  return Date.now() * 1_000_000
+}
+
 function writeStatus({ file, healthy = true, code, msg, startTime, callback } = {}) {
-  const currentTime = Number(process.hrtime.bigint())
+  const currentTime = getTime()
   const yaml = [
     `healthy: ${healthy}`,
     `status: '${msg}'`,
@@ -113,7 +120,7 @@ class HealthReporter {
       checkInterval = parseInt(checkInterval, 10) * 1_000
     }
 
-    this.#startTime = Number(process.hrtime.bigint())
+    this.#startTime = getTime()
 
     const uuid = crypto.randomUUID().replaceAll('-', '')
     this.#destFile = path.join(outDir, `health-${uuid}.yaml`)
diff --git a/test/unit/lib/health-reporter.test.js b/test/unit/lib/health-reporter.test.js
index 6ccf2183b3..a923845552 100644
--- a/test/unit/lib/health-reporter.test.js
+++ b/test/unit/lib/health-reporter.test.js
@@ -26,13 +26,13 @@ test.beforeEach((ctx) => {
   ctx.nr = {}
   ctx.nr.accessOrigin = fs.accessSync
   ctx.nr.writeFileOrig = fs.writeFile
-  ctx.nr.bigintOrig = process.hrtime.bigint
+  ctx.nr.nowOrig = Date.now
 
   fs.accessSync = () => true
 
-  let count = 0n
-  process.hrtime.bigint = () => {
-    count += 1n
+  let count = 0
+  Date.now = () => {
+    count += 1
     return count
   }
 
@@ -72,7 +72,7 @@ test.beforeEach((ctx) => {
 test.afterEach((ctx) => {
   fs.accessSync = ctx.nr.accessOrig
   fs.writeFile = ctx.nr.writeFileOrig
-  process.hrtime.bigint = ctx.nr.bigintOrig
+  Date.now = ctx.nr.nowOrig
 })
 
 test('requires enabled to be true', (t) => {
@@ -145,8 +145,8 @@ test('initializes and writes to destination', async (t) => {
         'healthy: true',
         "status: 'Healthy.'",
         'last_error: NR-APM-000',
-        'start_time_unix_nano: 1',
-        'status_time_unix_nano: 2'
+        'start_time_unix_nano: 1000000',
+        'status_time_unix_nano: 2000000'
       ].join('\n')
     )
     plan.deepStrictEqual(options, { encoding: 'utf8' })
@@ -236,8 +236,8 @@ test('stop leaves last error code in place', async (t) => {
         'healthy: false',
         "status: 'HTTP error communicating with New Relic.'",
         'last_error: NR-APM-004',
-        'start_time_unix_nano: 1',
-        'status_time_unix_nano: 3'
+        'start_time_unix_nano: 1000000',
+        'status_time_unix_nano: 3000000'
       ].join('\n')
     )
     callback()
@@ -268,8 +268,8 @@ test('stop sets shutdown status', async (t) => {
         'healthy: true',
         "status: 'Agent has shutdown.'",
         'last_error: NR-APM-099',
-        'start_time_unix_nano: 1',
-        'status_time_unix_nano: 3'
+        'start_time_unix_nano: 1000000',
+        'status_time_unix_nano: 3000000'
       ].join('\n')
     )
     callback()