Add feature management package version tracing (#153)

* add fm package version tracing

* update comment

* update

Author: zhiyuanliang-ms

rollup.config.mjs

@@ -4,7 +4,7 @@ import dts from "rollup-plugin-dts";
 
 export default [
   {
-    external: ["@azure/app-configuration", "@azure/keyvault-secrets", "@azure/core-rest-pipeline", "crypto", "dns/promises"],
+    external: ["@azure/app-configuration", "@azure/keyvault-secrets", "@azure/core-rest-pipeline", "crypto", "dns/promises", "@microsoft/feature-management"],
     input: "src/index.ts",
     output: [
       {

src/AzureAppConfigurationImpl.ts

@@ -33,6 +33,7 @@ import {
     CONDITIONS_KEY_NAME,
     CLIENT_FILTERS_KEY_NAME
 } from "./featureManagement/constants.js";
+import { FM_PACKAGE_NAME } from "./requestTracing/constants.js";
 import { AzureKeyVaultKeyValueAdapter } from "./keyvault/AzureKeyVaultKeyValueAdapter.js";
 import { RefreshTimer } from "./refresh/RefreshTimer.js";
 import { RequestTracingOptions, getConfigurationSettingWithTrace, listConfigurationSettingsWithTrace, requestTracingEnabled } from "./requestTracing/utils.js";
@@ -65,6 +66,7 @@ export class AzureAppConfigurationImpl implements AzureAppConfiguration {
     #isInitialLoadCompleted: boolean = false;
     #isFailoverRequest: boolean = false;
     #featureFlagTracing: FeatureFlagTracingOptions | undefined;
+    #fmVersion: string | undefined;
 
     // Refresh
     #refreshInProgress: boolean = false;
@@ -184,7 +186,8 @@ export class AzureAppConfigurationImpl implements AzureAppConfiguration {
             initialLoadCompleted: this.#isInitialLoadCompleted,
             replicaCount: this.#clientManager.getReplicaCount(),
             isFailoverRequest: this.#isFailoverRequest,
-            featureFlagTracing: this.#featureFlagTracing
+            featureFlagTracing: this.#featureFlagTracing,
+            fmVersion: this.#fmVersion
         };
     }
 
@@ -226,6 +229,7 @@ export class AzureAppConfigurationImpl implements AzureAppConfiguration {
      * Loads the configuration store for the first time.
      */
     async load() {
+        await this.#inspectFmPackage();
         await this.#loadSelectedAndWatchedKeyValues();
         if (this.#featureFlagEnabled) {
             await this.#loadFeatureFlags();
@@ -316,6 +320,21 @@ export class AzureAppConfigurationImpl implements AzureAppConfiguration {
         return new Disposable(remove);
     }
 
+    /**
+     * Inspects the feature management package version.
+     */
+    async #inspectFmPackage() {
+        if (this.#requestTracingEnabled && !this.#fmVersion) {
+            try {
+                // get feature management package version
+                const fmPackage = await import(FM_PACKAGE_NAME);
+                this.#fmVersion = fmPackage?.VERSION;
+            } catch (error) {
+                // ignore the error
+            }
+        }
+    }
+
     async #refreshTasks(): Promise<void> {
         const refreshTasks: Promise<boolean>[] = [];
         if (this.#refreshEnabled) {

src/ConfigurationClientManager.ts

@@ -85,6 +85,9 @@ export class ConfigurationClientManager {
             this.#isFailoverable = false;
             return;
         }
+        if (this.#dns) {
+            return;
+        }
 
         try {
             this.#dns = await import("dns/promises");

src/requestTracing/constants.ts

@@ -55,6 +55,10 @@ export const FAILOVER_REQUEST_TAG = "Failover";
 export const FEATURES_KEY = "Features";
 export const LOAD_BALANCE_CONFIGURED_TAG = "LB";
 
+// Feature management package
+export const FM_PACKAGE_NAME = "@microsoft/feature-management";
+export const FM_VERSION_KEY = "FMJsVer";
+
 // Feature flag usage tracing
 export const FEATURE_FILTER_TYPE_KEY = "Filter";
 export const CUSTOM_FILTER_KEY = "CSTM";

src/requestTracing/utils.ts

@@ -27,7 +27,8 @@ import {
     REPLICA_COUNT_KEY,
     FAILOVER_REQUEST_TAG,
     FEATURES_KEY,
-    LOAD_BALANCE_CONFIGURED_TAG
+    LOAD_BALANCE_CONFIGURED_TAG,
+    FM_VERSION_KEY
 } from "./constants";
 
 export interface RequestTracingOptions {
@@ -37,6 +38,7 @@ export interface RequestTracingOptions {
     replicaCount: number;
     isFailoverRequest: boolean;
     featureFlagTracing: FeatureFlagTracingOptions | undefined;
+    fmVersion: string | undefined;
 }
 
 // Utils
@@ -119,6 +121,9 @@ export function createCorrelationContextHeader(requestTracingOptions: RequestTra
     if (requestTracingOptions.replicaCount > 0) {
         keyValues.set(REPLICA_COUNT_KEY, requestTracingOptions.replicaCount.toString());
     }
+    if (requestTracingOptions.fmVersion) {
+        keyValues.set(FM_VERSION_KEY, requestTracingOptions.fmVersion);
+    }
 
     // Compact tags: Features=LB+...
     if (appConfigOptions?.loadBalancingEnabled) {