From da297233f0ecd7a6db4db62dbda7e734c02566ee Mon Sep 17 00:00:00 2001
From: Bastian Krol <bastian.krol@dash0.com>
Date: Tue, 25 Jun 2024 10:10:17 +0200
Subject: [PATCH] fix: lookup of own package.json in published package

In the published package, the path to our own package.json file (from
which we read the version for the resource attribute
telemetry.distro.version) is different compared to development.
---
 src/init.ts | 60 +++++++++++++++++++++++++++++++++++++++++------------
 1 file changed, 47 insertions(+), 13 deletions(-)

diff --git a/src/init.ts b/src/init.ts
index ecdfb13..1941554 100644
--- a/src/init.ts
+++ b/src/init.ts
@@ -14,16 +14,43 @@ import { NodeSDK, NodeSDKConfiguration } from '@opentelemetry/sdk-node';
 import { BatchSpanProcessor, SpanProcessor } from '@opentelemetry/sdk-trace-base';
 import { ConsoleSpanExporter } from '@opentelemetry/sdk-trace-node';
 
-import { version } from '../package.json';
-
 import PodUidDetector from './detectors/node/opentelemetry-resource-detector-kubernetes-pod';
 import ServiceNameFallbackDetector from './detectors/node/opentelemetry-resource-detector-service-name-fallback';
 import { FileSpanExporter } from './util/FileSpanExporter';
 import { hasOptedIn, hasOptedOut, parseNumericEnvironmentVariableWithDefault } from './util/environment';
 
+const logPrefix = 'Dash0 OpenTelemetry distribution for Node.js:';
 const debugOutput = hasOptedIn('DASH0_DEBUG');
 
-printDebugOutput('Dash0 OpenTelemetry distribution for Node.js: Starting NodeSDK.');
+let packageJson;
+let version: string;
+try {
+  // In the published package, the transpiled JS files are in dist/src/init.js, therefore the relative path to
+  // package.json is two levels above the directory of init.js.
+  packageJson = require('../../package.json');
+} catch (e1) {
+  try {
+    // In development, the directory is just src, therefore the relative path to package.json is only one level above.
+    packageJson = require('../package.json');
+  } catch (e2) {
+    printDebugStderr(
+      'Unable to find our own package.json file, will not transmit telemetry.distro.version. This warning can be safely ignored.',
+      e1,
+      e1,
+    );
+  }
+}
+// Since we read the package.json from two possible relative paths, we are extra-careful to make sure we actually are
+// reading from our own package.json file, hence the name check.
+if (packageJson && packageJson.name === '@dash0hq/opentelemetry') {
+  version = packageJson.version;
+} else {
+  printDebugStderr(
+    `Unexpected package name in our own package.json: ${packageJson.name}, will not transmit telemetry.distro.version. This warning can be safely ignored.`,
+  );
+}
+
+printDebugStdout('Starting NodeSDK.');
 
 let sdkShutdownHasBeenCalled = false;
 
@@ -48,7 +75,7 @@ sdk.start();
 createBootstrapSpanIfRequested();
 installProcessExitHandlers();
 
-printDebugOutput('Dash0 OpenTelemetry distribution for Node.js: NodeSDK started.');
+printDebugStdout('NodeSDK started.');
 
 function spanProcessors(): SpanProcessor[] {
   const spanProcessors: SpanProcessor[] = [
@@ -105,10 +132,13 @@ function createInstrumentationConfig(): any {
 }
 
 function resource() {
-  return new Resource({
+  const distroResourceAttributes: any = {
     'telemetry.distro.name': 'dash0-nodejs',
-    'telemetry.distro.version': version,
-  });
+  };
+  if (version) {
+    distroResourceAttributes['telemetry.distro.version'] = version;
+  }
+  return new Resource(distroResourceAttributes);
 }
 
 function resourceDetectors(): (Detector | DetectorSync)[] {
@@ -165,11 +195,9 @@ async function gracefulSdkShutdown(callProcessExit: boolean) {
     sdkShutdownHasBeenCalled = true;
     await sdk.shutdown();
 
-    printDebugOutput(
-      'Dash0 OpenTelemetry distribution for Node.js: OpenTelemetry SDK has been shut down successfully.',
-    );
+    printDebugStdout('OpenTelemetry SDK has been shut down successfully.');
   } catch (err) {
-    console.error('Dash0 OpenTelemetry distribution for Node.js: Error shutting down the OpenTelemetry SDK:', err);
+    console.error(logPrefix, 'Error shutting down the OpenTelemetry SDK:', err);
   } finally {
     if (callProcessExit) {
       process.exit(0);
@@ -199,8 +227,14 @@ function executePromiseWithTimeout(promise: Promise<any>, timeoutMillis: number,
   });
 }
 
-function printDebugOutput(message: string) {
+function printDebugStdout(message: string, ...additional: any[]) {
+  if (debugOutput) {
+    console.log(logPrefix, message, ...additional);
+  }
+}
+
+function printDebugStderr(message: string, ...additional: any[]) {
   if (debugOutput) {
-    console.log(message);
+    console.error(logPrefix, message, ...additional);
   }
 }