test: added additional test

Author: aryamohanan

packages/core/src/tracing/opentelemetry-instrumentations/opentelemetryApi.js

@@ -8,8 +8,24 @@
  * Exports the singleton OpenTelemetry API instance from the root-level
  * @opentelemetry installation in node_modules.
  *
- * This ensures that all instrumentations share the same API instance,
- * preventing conflicts that can occur when multiple versions (root vs nested)
+ * Resolution Logic:
+ *   1. Attempt to resolve @opentelemetry/api from the current working directory (root-level).
+ *   2. If not found, fall back to a nested (child) installation of @opentelemetry/api.
+ *
+ * This ensures that all instrumentations share the same API instance when possible,
+ * avoiding conflicts that can arise when multiple versions (root vs nested)
  * are loaded within the same process.
+ *
+* Example structure:
+ * ├── node_modules/@opentelemetry/api/      # root (preferred)
+ * └── packages/service/node_modules/@opentelemetry/api/  # fallback
  */
-module.exports = require(require.resolve('@opentelemetry/api', { paths: [process.cwd()] }));
+let api;
+
+try {
+  api = require(require.resolve('@opentelemetry/api', { paths: [process.cwd()] }));
+} catch {
+  api = require('@opentelemetry/api');
+}
+
+module.exports = api;

packages/core/test/tracing/opentelemetry/otelApi_test.js

@@ -0,0 +1,97 @@
+/*
+ * (c) Copyright IBM Corp. 2025
+ */
+
+'use strict';
+
+const path = require('path');
+const fs = require('fs');
+const Module = require('module');
+const { expect } = require('chai');
+
+describe('opentelemetry/api module', () => {
+  let tempDir;
+  let originalCwd;
+  let originalResolve;
+
+  before(() => {
+    tempDir = fs.mkdtempSync(path.join(__dirname, 'tempDir-'));
+    originalCwd = process.cwd();
+    process.chdir(tempDir);
+
+    const makeModule = (filePath, content) => {
+      fs.mkdirSync(path.dirname(filePath), { recursive: true });
+      fs.writeFileSync(filePath, content);
+    };
+
+    /**
+     * test structure:
+     *
+     * ├── node_modules/
+     * │   └── @opentelemetry/
+     * │       └── api/                      # root API
+     * │           └── index.js
+     * └── packages/
+     *     └── service/
+     *         └── node_modules/
+     *             └── @opentelemetry/
+     *                 └── api/              # fallback API
+     *                     └── index.js
+     */
+    makeModule(
+      path.join(tempDir, 'node_modules/@opentelemetry/api/index.js'),
+      "module.exports = { __source: 'root-api' };"
+    );
+
+    makeModule(
+      path.join(tempDir, 'packages/service/node_modules/@opentelemetry/api/index.js'),
+      "module.exports = { __source: 'child-api' };"
+    );
+
+    originalResolve = Module._resolveFilename;
+    Module._resolveFilename = function (request, parent, isMain, options) {
+      if (request === '@opentelemetry/api') {
+        const rootApi = path.join(tempDir, 'node_modules/@opentelemetry/api/index.js');
+        const childApi = path.join(tempDir, 'packages/service/node_modules/@opentelemetry/api/index.js');
+
+        if (options?.paths?.includes(process.cwd())) {
+          if (fs.existsSync(path.join(process.cwd(), 'node_modules/@opentelemetry/api/index.js'))) {
+            return path.join(process.cwd(), 'node_modules/@opentelemetry/api/index.js');
+          }
+          throw new Error('Cannot find local module');
+        }
+
+        if (fs.existsSync(rootApi)) return rootApi;
+        if (fs.existsSync(childApi)) return childApi;
+      }
+
+      return originalResolve.call(this, request, parent, isMain, options);
+    };
+  });
+
+  after(() => {
+    process.chdir(originalCwd);
+    Module._resolveFilename = originalResolve;
+    fs.rmSync(tempDir, { recursive: true, force: true });
+  });
+
+  it('should load @opentelemetry/api from the root-level node_modules by default', () => {
+    process.chdir(tempDir);
+
+    delete require.cache[require.resolve('../../../src/tracing/opentelemetry-instrumentations/opentelemetryApi')];
+    const otelApi = require('../../../src/tracing/opentelemetry-instrumentations/opentelemetryApi');
+
+    expect(otelApi.__source).to.equal('root-api');
+  });
+
+  it('should fall back to @opentelemetry/api in child node_modules if root-level is missing', () => {
+    fs.rmSync(path.join(tempDir, 'node_modules/@opentelemetry'), { recursive: true, force: true });
+
+    const nestedPath = path.join(tempDir, 'packages/service');
+    process.chdir(nestedPath);
+
+    delete require.cache[require.resolve('../../../src/tracing/opentelemetry-instrumentations/opentelemetryApi')];
+    const otelApi = require('../../../src/tracing/opentelemetry-instrumentations/opentelemetryApi');
+    expect(otelApi.__source).to.equal('child-api');
+  });
+});