update

Author: zhiyuanliang-ms

src/appConfigurationImpl.ts

@@ -1,7 +1,7 @@
 // Copyright (c) Microsoft Corporation.
 // Licensed under the MIT license.
 
-import { WatchedSetting } from "../watchedSetting.js";
+import { WatchedSetting } from "../types.js";
 
 export const DEFAULT_REFRESH_INTERVAL_IN_MS = 30_000;
 export const MIN_REFRESH_INTERVAL_IN_MS = 1_000;

src/refresh/refreshOptions.ts

@@ -1,6 +1,8 @@
 // Copyright (c) Microsoft Corporation.
 // Licensed under the MIT license.
 
+import { ConfigurationSettingId } from "@azure/app-configuration";
+
 /**
  * SettingSelector is used to select key-values from Azure App Configuration based on keys and labels.
  */
@@ -58,7 +60,7 @@ export enum KeyFilter {
      * Matches all key-values.
      */
     Any = "*"
-}
+};
 
 /**
  * LabelFilter is used to filter key-values based on labels.
@@ -68,7 +70,7 @@ export enum LabelFilter {
      * Matches key-values without a label.
      */
     Null = "\0"
-}
+};
 
 /**
  * TagFilter is used to filter key-values based on tags.
@@ -78,4 +80,26 @@ export enum TagFilter {
      * Represents empty tag value.
      */
     Null = ""
+};
+
+export type WatchedSetting = {
+    /**
+     * The key for this setting.
+     */
+    key: string;
+
+    /**
+     * The label for this setting.
+     * Leaving this undefined means this setting does not have a label.
+     */
+    label?: string;
 }
+
+export type SettingWatcher = {
+    etag?: string;
+    timestamp: Date;
+}
+
+export type PagedSettingsWatcher = SettingSelector & {
+    pageWatchers?: SettingWatcher[]
+};

src/types.ts

@@ -180,10 +180,10 @@ describe("loadFromAzureFrontDoor", function() {
         ]));
 
         stub.onCall(2).returns(getCachedIterator([
-            { items: [ff_updated], response: { status: 200, headers: createTimestampHeaders("2025-09-07T00:00:00Z") } }
+            { items: [ff_updated], response: { status: 200, headers: createTimestampHeaders("2025-09-07T00:00:03Z") } }
         ]));
         stub.onCall(3).returns(getCachedIterator([
-            { items: [ff_updated], response: { status: 200, headers: createTimestampHeaders("2025-09-07T00:00:00Z") } }
+            { items: [ff_updated], response: { status: 200, headers: createTimestampHeaders("2025-09-07T00:00:03Z") } }
         ]));
 
         const appConfig = await loadFromAzureFrontDoor(createMockedAzureFrontDoorEndpoint(), {
@@ -209,6 +209,7 @@ describe("loadFromAzureFrontDoor", function() {
     });
 
     it("should keep refreshing key value until cache expires", async () => {
+        let refreshSuccessfulCount = 0;
         const sentinel = createMockedKeyValue({ key: "sentinel", value: "initial value" });
         const sentinel_updated = createMockedKeyValue({ key: "sentinel", value: "updated value" });
         const kv1 = createMockedKeyValue({ key: "app.key1", value: "value1" });
@@ -221,9 +222,7 @@ describe("loadFromAzureFrontDoor", function() {
         getStub.onCall(0).returns(Promise.resolve({ statusCode: 200, _response: { headers: createTimestampHeaders("2025-09-07T00:00:00Z") }, ...sentinel } as any));
         getStub.onCall(1).returns(Promise.resolve({ statusCode: 200, _response: { headers: createTimestampHeaders("2025-09-07T00:00:01Z") }, ...sentinel_updated } as any));
         getStub.onCall(2).returns(Promise.resolve({ statusCode: 200, _response: { headers: createTimestampHeaders("2025-09-07T00:00:01Z") }, ...sentinel_updated } as any));
-
-        getStub.onCall(3).returns(Promise.resolve({ statusCode: 200, _response: { headers: createTimestampHeaders("2025-09-07T00:00:01Z") }, ...sentinel_updated } as any));
-        getStub.onCall(4).returns(Promise.resolve({ statusCode: 200, _response: { headers: createTimestampHeaders("2025-09-07T00:00:01Z") }, ...sentinel_updated } as any));
+        getStub.onCall(4).returns(Promise.resolve({ statusCode: 200, _response: { headers: createTimestampHeaders("2025-09-07T00:00:00Z") }, ...sentinel } as any)); // server old value from another cache server
 
         listStub.onCall(0).returns(getCachedIterator([
             { items: [kv1, kv2], response: { status: 200, headers: createTimestampHeaders("2025-09-07T00:00:00Z") } }
@@ -246,19 +245,30 @@ describe("loadFromAzureFrontDoor", function() {
             }
         });
 
+        appConfig.onRefresh(() => {
+            refreshSuccessfulCount++;
+        });
+
         expect(appConfig.get("app.key2")).to.equal("value2");
 
         await sleepInMs(1500);
         await appConfig.refresh();
 
         // cdn cache hasn't expired, even if the sentinel key changed, key2 should still return the old value
         expect(appConfig.get("app.key2")).to.equal("value2");
+        expect(refreshSuccessfulCount).to.equal(0);
 
         await sleepInMs(1500);
         await appConfig.refresh();
+        expect(refreshSuccessfulCount).to.equal(1);
 
         // cdn cache has expired, key2 should return the updated value even if sentinel remains the same
         expect(appConfig.get("app.key2")).to.equal("value2-updated");
+
+        await sleepInMs(1500);
+        // even if the sentinel is different from previous value, but the timestamp is older, it should not trigger refresh
+        await appConfig.refresh();
+        expect(refreshSuccessfulCount).to.equal(1);
     });
 });
 /* eslint-ensable @typescript-eslint/no-unused-expressions */

src/watchedSetting.ts

@@ -144,7 +144,7 @@ describe("dynamic refresh", function () {
             }
         });
         expect(listKvRequestCount).eq(1);
-        expect(getKvRequestCount).eq(0);
+        expect(getKvRequestCount).eq(1);
         expect(settings).not.undefined;
         expect(settings.get("app.settings.fontColor")).eq("red");
         expect(settings.get("app.settings.fontSize")).eq("40");
@@ -156,13 +156,13 @@ describe("dynamic refresh", function () {
         await settings.refresh();
         expect(settings.get("app.settings.fontColor")).eq("red");
         expect(listKvRequestCount).eq(1); // no more request should be sent during the refresh interval
-        expect(getKvRequestCount).eq(0); // no more request should be sent during the refresh interval
+        expect(getKvRequestCount).eq(1); // no more request should be sent during the refresh interval
 
         // after refreshInterval, should really refresh
         await sleepInMs(2 * 1000 + 1);
         await settings.refresh();
         expect(listKvRequestCount).eq(2);
-        expect(getKvRequestCount).eq(1);
+        expect(getKvRequestCount).eq(2);
         expect(settings.get("app.settings.fontColor")).eq("blue");
     });
 
@@ -178,7 +178,7 @@ describe("dynamic refresh", function () {
             }
         });
         expect(listKvRequestCount).eq(1);
-        expect(getKvRequestCount).eq(0);
+        expect(getKvRequestCount).eq(1);
         expect(settings).not.undefined;
         expect(settings.get("app.settings.fontColor")).eq("red");
         expect(settings.get("app.settings.fontSize")).eq("40");
@@ -192,7 +192,7 @@ describe("dynamic refresh", function () {
         await sleepInMs(2 * 1000 + 1);
         await settings.refresh();
         expect(listKvRequestCount).eq(2);
-        expect(getKvRequestCount).eq(2); // one conditional request to detect change and one request as part of loading all kvs (because app.settings.fontColor doesn't exist in the response of listKv request)
+        expect(getKvRequestCount).eq(2); // one conditional request to detect change
         expect(settings.get("app.settings.fontColor")).eq(undefined);
     });
 
@@ -208,7 +208,7 @@ describe("dynamic refresh", function () {
             }
         });
         expect(listKvRequestCount).eq(1);
-        expect(getKvRequestCount).eq(0);
+        expect(getKvRequestCount).eq(1);
         expect(settings).not.undefined;
         expect(settings.get("app.settings.fontColor")).eq("red");
         expect(settings.get("app.settings.fontSize")).eq("40");
@@ -217,7 +217,7 @@ describe("dynamic refresh", function () {
         await sleepInMs(2 * 1000 + 1);
         await settings.refresh();
         expect(listKvRequestCount).eq(1);
-        expect(getKvRequestCount).eq(1);
+        expect(getKvRequestCount).eq(2);
         expect(settings.get("app.settings.fontSize")).eq("40");
     });
 
@@ -234,19 +234,19 @@ describe("dynamic refresh", function () {
             }
         });
         expect(listKvRequestCount).eq(1);
-        expect(getKvRequestCount).eq(0);
+        expect(getKvRequestCount).eq(2); // two getKv requests for two watched settings
         expect(settings).not.undefined;
         expect(settings.get("app.settings.fontColor")).eq("red");
         expect(settings.get("app.settings.fontSize")).eq("40");
 
         // change setting
         addSetting("app.settings.bgColor", "white");
-        updateSetting("app.settings.fontSize", "50");
+        updateSetting("app.settings.fontColor", "blue");
         await sleepInMs(2 * 1000 + 1);
         await settings.refresh();
         expect(listKvRequestCount).eq(2);
-        expect(getKvRequestCount).eq(2); // two getKv request for two watched settings
-        expect(settings.get("app.settings.fontSize")).eq("50");
+        expect(getKvRequestCount).eq(3);
+        expect(settings.get("app.settings.fontColor")).eq("blue");
         expect(settings.get("app.settings.bgColor")).eq("white");
     });
 
@@ -284,7 +284,7 @@ describe("dynamic refresh", function () {
         await sleepInMs(2 * 1000 + 1);
         await settings.refresh(); // should continue to refresh even if sentinel key doesn't change now
         expect(listKvRequestCount).eq(2);
-        expect(getKvRequestCount).eq(4);
+        expect(getKvRequestCount).eq(3);
         expect(settings.get("app.settings.bgColor")).eq("white");
     });
 
@@ -370,7 +370,7 @@ describe("dynamic refresh", function () {
             }
         });
         expect(listKvRequestCount).eq(1);
-        expect(getKvRequestCount).eq(1); // app.settings.bgColor doesn't exist in the response of listKv request, so an additional getKv request is made to get it.
+        expect(getKvRequestCount).eq(1);
         expect(settings).not.undefined;
         expect(settings.get("app.settings.fontColor")).eq("red");
         expect(settings.get("app.settings.fontSize")).eq("40");
@@ -464,7 +464,7 @@ describe("dynamic refresh", function () {
             }
         });
         expect(listKvRequestCount).eq(1);
-        expect(getKvRequestCount).eq(0);
+        expect(getKvRequestCount).eq(1);
         expect(settings).not.undefined;
         expect(settings.get("app.settings.fontColor")).eq("red");
 
@@ -477,12 +477,12 @@ describe("dynamic refresh", function () {
             settings.refresh(); // refresh "concurrently"
         }
         expect(listKvRequestCount).to.be.at.most(2);
-        expect(getKvRequestCount).to.be.at.most(1);
+        expect(getKvRequestCount).to.be.at.most(2);
 
         await sleepInMs(1000); // wait for all 5 refresh attempts to finish
 
         expect(listKvRequestCount).eq(2);
-        expect(getKvRequestCount).eq(1);
+        expect(getKvRequestCount).eq(2);
         expect(settings.get("app.settings.fontColor")).eq("blue");
     });
 

test/cdn.test.ts

@@ -6,10 +6,12 @@ import * as chai from "chai";
 import chaiAsPromised from "chai-as-promised";
 chai.use(chaiAsPromised);
 const expect = chai.expect;
+import { AppConfigurationClient } from "@azure/app-configuration";
 import { HttpRequestHeadersPolicy, createMockedConnectionString, createMockedKeyValue, createMockedFeatureFlag, createMockedTokenCredential, mockAppConfigurationClientListConfigurationSettings, restoreMocks, sinon, sleepInMs } from "./utils/testHelper.js";
 import { ConfigurationClientManager } from "../src/configurationClientManager.js";
 import { load, loadFromAzureFrontDoor } from "../src/index.js";
 import { isBrowser } from "../src/requestTracing/utils.js";
+import { get } from "http";
 
 const CORRELATION_CONTEXT_HEADER_NAME = "Correlation-Context";
 
@@ -211,16 +213,25 @@ describe("request tracing", function () {
             value: "red"
         }].map(createMockedKeyValue)]);
 
+        const sentinel = createMockedKeyValue({ key: "sentinel", value: "initial value" });
+        const getStub = sinon.stub(AppConfigurationClient.prototype, "getConfigurationSetting");
+        getStub.onCall(0).returns(Promise.resolve({ statusCode: 200, ...sentinel } as any));
+
         const settings = await load(createMockedConnectionString(fakeEndpoint), {
             clientOptions,
             refreshOptions: {
                 enabled: true,
                 refreshIntervalInMs: 1_000,
                 watchedSettings: [{
-                    key: "app.settings.fontColor"
+                    key: "sentinel"
                 }]
             }
         });
+
+        expect(settings.get("app.settings.fontColor")).eq("red"); // initial load should succeed
+         // we only mocked getConfigurationSetting for initial load, so the watch request during refresh will still use the SDK's pipeline, then the headerPolicy can capture the headers
+        getStub.restore();
+
         await sleepInMs(1_000 + 1_000);
         try {
             await settings.refresh();