fix(azure-functions-resource-detector): Update Azure Functions Detector to Consider WEBSITE_SKU (#2251)

* fix: Update the functions detector check to include SKU.

* Resolve PR comments.

---------

Co-authored-by: Hector Hernandez <[email protected]>
Co-authored-by: Marc Pichler <[email protected]>

Author: 3 people

detectors/node/opentelemetry-resource-detector-azure/src/detectors/AzureAppServiceDetector.ts

@@ -24,7 +24,6 @@ import {
   WEBSITE_SITE_NAME,
   WEBSITE_SLOT_NAME,
   CLOUD_RESOURCE_ID_RESOURCE_ATTRIBUTE,
-  FUNCTIONS_VERSION,
 } from '../types';
 import {
   SEMRESATTRS_CLOUD_REGION,
@@ -37,7 +36,7 @@ import {
   CLOUDPROVIDERVALUES_AZURE,
   CLOUDPLATFORMVALUES_AZURE_APP_SERVICE,
 } from '@opentelemetry/semantic-conventions';
-import { getAzureResourceUri } from '../utils';
+import { getAzureResourceUri, isAzureFunction } from '../utils';
 
 const APP_SERVICE_ATTRIBUTE_ENV_VARS = {
   [SEMRESATTRS_CLOUD_REGION]: REGION_NAME,
@@ -55,8 +54,7 @@ class AzureAppServiceDetector implements DetectorSync {
   detect(): IResource {
     let attributes = {};
     const websiteSiteName = process.env[WEBSITE_SITE_NAME];
-    const isAzureFunction = !!process.env[FUNCTIONS_VERSION];
-    if (websiteSiteName && !isAzureFunction) {
+    if (websiteSiteName && !isAzureFunction()) {
       attributes = {
         ...attributes,
         [SEMRESATTRS_SERVICE_NAME]: websiteSiteName,

detectors/node/opentelemetry-resource-detector-azure/src/detectors/AzureFunctionsDetector.ts

@@ -29,13 +29,12 @@ import {
 } from '@opentelemetry/semantic-conventions';
 import {
   WEBSITE_SITE_NAME,
-  FUNCTIONS_VERSION,
   WEBSITE_INSTANCE_ID,
   FUNCTIONS_MEM_LIMIT,
   REGION_NAME,
   CLOUD_RESOURCE_ID_RESOURCE_ATTRIBUTE,
 } from '../types';
-import { getAzureResourceUri } from '../utils';
+import { getAzureResourceUri, isAzureFunction } from '../utils';
 
 const AZURE_FUNCTIONS_ATTRIBUTE_ENV_VARS = {
   [SEMRESATTRS_SERVICE_NAME]: WEBSITE_SITE_NAME,
@@ -51,13 +50,13 @@ class AzureFunctionsDetector implements DetectorSync {
   detect(): IResource {
     let attributes = {};
     const serviceName = process.env[WEBSITE_SITE_NAME];
-    const functionVersion = process.env[FUNCTIONS_VERSION];
 
     /**
      * Checks that we are operating within an Azure Function using the function version since WEBSITE_SITE_NAME
      * will exist in Azure App Service as well and detectors should be mutually exclusive.
+     * If the function version is not present, we check for the website sku to determine if it is a function.
      */
-    if (serviceName && functionVersion) {
+    if (serviceName && isAzureFunction()) {
       const functionInstance = process.env[WEBSITE_INSTANCE_ID];
       const functionMemLimit = process.env[FUNCTIONS_MEM_LIMIT];
 

detectors/node/opentelemetry-resource-detector-azure/src/types.ts

@@ -25,6 +25,7 @@ export const WEBSITE_OWNER_NAME = 'WEBSITE_OWNER_NAME';
 export const WEBSITE_RESOURCE_GROUP = 'WEBSITE_RESOURCE_GROUP';
 export const WEBSITE_SITE_NAME = 'WEBSITE_SITE_NAME';
 export const WEBSITE_SLOT_NAME = 'WEBSITE_SLOT_NAME';
+export const WEBSITE_SKU = 'WEBSITE_SKU';
 
 export const FUNCTIONS_VERSION = 'FUNCTIONS_EXTENSION_VERSION';
 export const FUNCTIONS_MEM_LIMIT = 'WEBSITE_MEMORY_LIMIT_MB';

detectors/node/opentelemetry-resource-detector-azure/src/utils.ts

@@ -14,7 +14,12 @@
  * limitations under the License.
  */
 
-import { WEBSITE_OWNER_NAME, WEBSITE_RESOURCE_GROUP } from './types';
+import {
+  FUNCTIONS_VERSION,
+  WEBSITE_OWNER_NAME,
+  WEBSITE_RESOURCE_GROUP,
+  WEBSITE_SKU,
+} from './types';
 
 export function getAzureResourceUri(
   websiteSiteName: string
@@ -33,3 +38,10 @@ export function getAzureResourceUri(
 
   return `/subscriptions/${subscriptionId}/resourceGroups/${websiteResourceGroup}/providers/Microsoft.Web/sites/${websiteSiteName}`;
 }
+
+export function isAzureFunction(): boolean {
+  return !!(
+    process.env[FUNCTIONS_VERSION] ||
+    process.env[WEBSITE_SKU] === 'FlexConsumption'
+  );
+}

detectors/node/opentelemetry-resource-detector-azure/test/detectors/AzureFunctionsDetector.test.ts

@@ -102,3 +102,27 @@ describe('AzureFunctionsDetector', () => {
     );
   });
 });
+
+it('should detect azure functions if websiteSku is defined as FlexConsumption', () => {
+  assert.ok(!process.env.WEBSITE_SKU && !process.env.FUNCTIONS_VERSION);
+  process.env.WEBSITE_SITE_NAME = 'test-service';
+  process.env.REGION_NAME = 'test-region';
+  process.env.WEBSITE_INSTANCE_ID = 'test-instance-id';
+  process.env.WEBSITE_SKU = 'FlexConsumption';
+  process.env.WEBSITE_MEMORY_LIMIT_MB = '1000';
+  process.env.WEBSITE_OWNER_NAME = 'test-owner-name';
+  process.env.WEBSITE_RESOURCE_GROUP = 'test-resource-group';
+
+  const resource = detectResourcesSync({
+    detectors: [azureFunctionsDetector, azureAppServiceDetector],
+  });
+  assert.ok(resource);
+  const attributes = resource.attributes;
+  assert.strictEqual(attributes[SEMRESATTRS_SERVICE_NAME], 'test-service');
+  assert.strictEqual(attributes[SEMRESATTRS_CLOUD_PROVIDER], 'azure');
+
+  // Should not detect app service values
+  assert.strictEqual(attributes[SEMRESATTRS_SERVICE_INSTANCE_ID], undefined);
+  assert.strictEqual(attributes[SEMRESATTRS_PROCESS_PID], process.pid);
+  delete process.env.WEBSITE_SKU;
+});