From 7b0cfd7325416a989894fed1288c131b4f67e3bc Mon Sep 17 00:00:00 2001
From: Zhiyuan Liang <zhiyuanliang@microsoft.com>
Date: Tue, 16 Sep 2025 23:21:18 +0800
Subject: [PATCH 01/21] add policy

---
 .../app-configuration/CHANGELOG.md            | 11 ++---
 .../src/appConfigurationClient.ts             |  4 +-
 .../src/generated/src/models/parameters.ts    |  2 +-
 .../src/internal/queryParamPolicy.ts          | 42 +++++++++++++++++++
 ...{synctokenpolicy.ts => syncTokenPolicy.ts} |  0
 .../test/internal/node/http.spec.ts           |  2 +-
 6 files changed, 53 insertions(+), 8 deletions(-)
 create mode 100644 sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts
 rename sdk/appconfiguration/app-configuration/src/internal/{synctokenpolicy.ts => syncTokenPolicy.ts} (100%)

diff --git a/sdk/appconfiguration/app-configuration/CHANGELOG.md b/sdk/appconfiguration/app-configuration/CHANGELOG.md
index 3c57d1b1f0d5..3f671bf1ca91 100644
--- a/sdk/appconfiguration/app-configuration/CHANGELOG.md
+++ b/sdk/appconfiguration/app-configuration/CHANGELOG.md
@@ -4,6 +4,8 @@
 
 ### Features Added
 
+- Added internal pipeline policy to normalize (case-insensitive alphabetical) ordering of query parameters for deterministic request URLs.
+
 ### Breaking Changes
 
 ### Bugs Fixed
@@ -13,11 +15,12 @@
 ## 1.9.0 (2025-04-08)
 
 ### Features Added
- - Include all the changes from 1.9.0-beta.1 version
- 
+
+- Include all the changes from 1.9.0-beta.1 version
+
 ### Other Changes
 
-- Update README with a link to [*`@azure/app-configuration-provider`*](https://www.npmjs.com/package/@azure/app-configuration-provider). [#33152](https://github.com/Azure/azure-sdk-for-js/pull/33152)
+- Update README with a link to [_`@azure/app-configuration-provider`_](https://www.npmjs.com/package/@azure/app-configuration-provider). [#33152](https://github.com/Azure/azure-sdk-for-js/pull/33152)
 
 ## 1.9.0-beta.1 (2025-03-11)
 
@@ -144,7 +147,6 @@ See [`listConfigurationSettings.ts`](https://github.com/Azure/azure-sdk-for-js/t
 ### Other Changes
 
 - Updated our `@azure/core-tracing` dependency to the latest version (1.0.0).
-
   - Notable changes include Removal of `@opentelemetry/api` as a transitive dependency and ensuring that the active context is properly propagated.
   - Customers who would like to continue using OpenTelemetry driven tracing should visit our [OpenTelemetry Instrumentation](https://www.npmjs.com/package/@azure/opentelemetry-instrumentation-azure-sdk) package for instructions.
 
@@ -181,7 +183,6 @@ See [`listConfigurationSettings.ts`](https://github.com/Azure/azure-sdk-for-js/t
 ### Features Added
 
 - Special configuration settings - feature flag and secret reference are now supported. 🎉
-
   - For types, use `ConfigurationSetting<FeatureFlagValue>` and `ConfigurationSetting<SecretReferenceValue>`.
   - Use `parseFeatureFlag` and `parseSecretReference` methods to parse the configuration settings into feature flag and secret reference respectively.
 
diff --git a/sdk/appconfiguration/app-configuration/src/appConfigurationClient.ts b/sdk/appconfiguration/app-configuration/src/appConfigurationClient.ts
index f87f8537eccc..62848b9407af 100644
--- a/sdk/appconfiguration/app-configuration/src/appConfigurationClient.ts
+++ b/sdk/appconfiguration/app-configuration/src/appConfigurationClient.ts
@@ -56,7 +56,8 @@ import type { PagedAsyncIterableIterator, PagedResult } from "@azure/core-paging
 import { getPagedAsyncIterator } from "@azure/core-paging";
 import type { PipelinePolicy, RestError } from "@azure/core-rest-pipeline";
 import { bearerTokenAuthenticationPolicy } from "@azure/core-rest-pipeline";
-import { SyncTokens, syncTokenPolicy } from "./internal/synctokenpolicy.js";
+import { SyncTokens, syncTokenPolicy } from "./internal/syncTokenPolicy.js";
+import { urlQueryParamsNormalizationPolicy } from "./internal/queryParamPolicy.js";
 import type { TokenCredential } from "@azure/core-auth";
 import { isTokenCredential } from "@azure/core-auth";
 import type {
@@ -195,6 +196,7 @@ export class AppConfigurationClient {
       internalClientPipelineOptions,
     );
     this.client.pipeline.addPolicy(authPolicy, { phase: "Sign" });
+    this.client.pipeline.addPolicy(urlQueryParamsNormalizationPolicy(), { afterPhase: "Sign" });
     this.client.pipeline.addPolicy(syncTokenPolicy(this._syncTokens), { afterPhase: "Retry" });
   }
 
diff --git a/sdk/appconfiguration/app-configuration/src/generated/src/models/parameters.ts b/sdk/appconfiguration/app-configuration/src/generated/src/models/parameters.ts
index 095ab9349e2b..db83490d75a3 100644
--- a/sdk/appconfiguration/app-configuration/src/generated/src/models/parameters.ts
+++ b/sdk/appconfiguration/app-configuration/src/generated/src/models/parameters.ts
@@ -76,7 +76,7 @@ export const apiVersion: OperationQueryParameter = {
 export const after: OperationQueryParameter = {
   parameterPath: ["options", "after"],
   mapper: {
-    serializedName: "After",
+    serializedName: "after",
     type: {
       name: "String",
     },
diff --git a/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts b/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts
new file mode 100644
index 000000000000..0fe09a35a58b
--- /dev/null
+++ b/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts
@@ -0,0 +1,42 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT License.
+
+import type { PipelinePolicy } from "@azure/core-rest-pipeline";
+
+/**
+ * A policy factory for normalizing query parameters in outgoing requests.
+ * @internal
+ */
+export function urlQueryParamsNormalizationPolicy(): PipelinePolicy {
+  return {
+    name: "UrlQueryParamsNormalizationPolicy",
+    async sendRequest(request, next) {
+      const qIndex = request.url.indexOf("?");
+      if (qIndex === -1) {
+        return next(request);
+      }
+
+      const base = request.url.substring(0, qIndex);
+      const queryString = request.url.substring(qIndex + 1);
+
+      if (!queryString.includes("&")) {
+        return next(request);
+      }
+
+      const params = new URLSearchParams(queryString);
+      const collected: Array<{ name: string; value: string; lower: string }> = [];
+      for (const [name, value] of params.entries()) {
+        collected.push({ name, value, lower: name.toLowerCase() });
+      }
+      if (collected.length > 1) {
+        collected.sort((a, b) => (a.lower < b.lower ? -1 : a.lower > b.lower ? 1 : 0));
+        const sorted = new URLSearchParams();
+        for (const p of collected) {
+          sorted.append(p.name, p.value);
+        }
+        Object.assign(request, { url: `${base}?${sorted.toString()}` });
+      }
+      return next(request);
+    },
+  };
+}
diff --git a/sdk/appconfiguration/app-configuration/src/internal/synctokenpolicy.ts b/sdk/appconfiguration/app-configuration/src/internal/syncTokenPolicy.ts
similarity index 100%
rename from sdk/appconfiguration/app-configuration/src/internal/synctokenpolicy.ts
rename to sdk/appconfiguration/app-configuration/src/internal/syncTokenPolicy.ts
diff --git a/sdk/appconfiguration/app-configuration/test/internal/node/http.spec.ts b/sdk/appconfiguration/app-configuration/test/internal/node/http.spec.ts
index b96bd4fbde1f..1c2b6e74a4ca 100644
--- a/sdk/appconfiguration/app-configuration/test/internal/node/http.spec.ts
+++ b/sdk/appconfiguration/app-configuration/test/internal/node/http.spec.ts
@@ -1,7 +1,7 @@
 // Copyright (c) Microsoft Corporation.
 // Licensed under the MIT License.
 
-import { SyncTokens, parseSyncToken } from "../../../src/internal/synctokenpolicy.js";
+import { SyncTokens, parseSyncToken } from "../../../src/internal/syncTokenPolicy.js";
 import {
   assertThrowsRestError,
   createAppConfigurationClientForTests,

From 1ffceb05234a5f9923eac048f411b0b64f20b8dc Mon Sep 17 00:00:00 2001
From: Zhiyuan Liang <zhiyuanliang@microsoft.com>
Date: Wed, 17 Sep 2025 15:20:47 +0800
Subject: [PATCH 02/21] add testcase

---
 .../src/appConfigurationClient.ts             |   4 +-
 .../src/internal/queryParamPolicy.ts          |  28 +--
 .../test/internal/queryParamPolicy.spec.ts    |  32 ++++
 .../test/public/queryParam.spec.ts            | 159 ++++++++++++++++++
 4 files changed, 208 insertions(+), 15 deletions(-)
 create mode 100644 sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts
 create mode 100644 sdk/appconfiguration/app-configuration/test/public/queryParam.spec.ts

diff --git a/sdk/appconfiguration/app-configuration/src/appConfigurationClient.ts b/sdk/appconfiguration/app-configuration/src/appConfigurationClient.ts
index 62848b9407af..6f512edcd7a3 100644
--- a/sdk/appconfiguration/app-configuration/src/appConfigurationClient.ts
+++ b/sdk/appconfiguration/app-configuration/src/appConfigurationClient.ts
@@ -57,7 +57,7 @@ import { getPagedAsyncIterator } from "@azure/core-paging";
 import type { PipelinePolicy, RestError } from "@azure/core-rest-pipeline";
 import { bearerTokenAuthenticationPolicy } from "@azure/core-rest-pipeline";
 import { SyncTokens, syncTokenPolicy } from "./internal/syncTokenPolicy.js";
-import { urlQueryParamsNormalizationPolicy } from "./internal/queryParamPolicy.js";
+import { urlQueryParamNormalizationPolicy } from "./internal/queryParamPolicy.js";
 import type { TokenCredential } from "@azure/core-auth";
 import { isTokenCredential } from "@azure/core-auth";
 import type {
@@ -196,7 +196,7 @@ export class AppConfigurationClient {
       internalClientPipelineOptions,
     );
     this.client.pipeline.addPolicy(authPolicy, { phase: "Sign" });
-    this.client.pipeline.addPolicy(urlQueryParamsNormalizationPolicy(), { afterPhase: "Sign" });
+    this.client.pipeline.addPolicy(urlQueryParamNormalizationPolicy());
     this.client.pipeline.addPolicy(syncTokenPolicy(this._syncTokens), { afterPhase: "Retry" });
   }
 
diff --git a/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts b/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts
index 0fe09a35a58b..f88bb953432e 100644
--- a/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts
+++ b/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts
@@ -4,12 +4,19 @@
 import type { PipelinePolicy } from "@azure/core-rest-pipeline";
 
 /**
- * A policy factory for normalizing query parameters in outgoing requests.
+ * A policy that normalizes query parameters for stable, canonical request URLs.
+ * Behavior:
+ * 1. All query parameter names are converted to lowercase (canonical form).
+ * 2. Parameters are sorted lexicographically by their lowercase names.
+ * 3. Relative order of duplicate names (ignoring case) is preserved (stable sort guarantee).
+ *
+ * This improves determinism for recordings and avoids casing-related cache misses.
+ * NOTE: Only enable if the target service treats parameter names case-insensitively.
  * @internal
  */
-export function urlQueryParamsNormalizationPolicy(): PipelinePolicy {
+export function urlQueryParamNormalizationPolicy(): PipelinePolicy {
   return {
-    name: "UrlQueryParamsNormalizationPolicy",
+    name: "urlQueryParamNormalizationPolicy",
     async sendRequest(request, next) {
       const qIndex = request.url.indexOf("?");
       if (qIndex === -1) {
@@ -18,11 +25,6 @@ export function urlQueryParamsNormalizationPolicy(): PipelinePolicy {
 
       const base = request.url.substring(0, qIndex);
       const queryString = request.url.substring(qIndex + 1);
-
-      if (!queryString.includes("&")) {
-        return next(request);
-      }
-
       const params = new URLSearchParams(queryString);
       const collected: Array<{ name: string; value: string; lower: string }> = [];
       for (const [name, value] of params.entries()) {
@@ -30,12 +32,12 @@ export function urlQueryParamsNormalizationPolicy(): PipelinePolicy {
       }
       if (collected.length > 1) {
         collected.sort((a, b) => (a.lower < b.lower ? -1 : a.lower > b.lower ? 1 : 0));
-        const sorted = new URLSearchParams();
-        for (const p of collected) {
-          sorted.append(p.name, p.value);
-        }
-        Object.assign(request, { url: `${base}?${sorted.toString()}` });
       }
+      const normalized = new URLSearchParams();
+      for (const p of collected) {
+        normalized.append(p.lower, p.value);
+      }
+      Object.assign(request, { url: `${base}?${normalized.toString()}` });
       return next(request);
     },
   };
diff --git a/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts b/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts
new file mode 100644
index 000000000000..109d9444358f
--- /dev/null
+++ b/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts
@@ -0,0 +1,32 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT License.
+
+import { describe, it, expect } from "vitest";
+import { urlQueryParamNormalizationPolicy } from "../../src/internal/queryParamPolicy.js";
+import { createPipelineRequest, createHttpHeaders } from "@azure/core-rest-pipeline";
+import type { PipelineRequest, PipelineResponse } from "@azure/core-rest-pipeline";
+
+function mockNext(returnStatus: number = 200) {
+  return async (request: PipelineRequest): Promise<PipelineResponse> => {
+    return {
+      request,
+      headers: createHttpHeaders({ "url-lookup": request.url }),
+      status: returnStatus,
+    } as PipelineResponse;
+  };
+}
+
+describe("urlQueryParamsNormalizationPolicy", () => {
+  it("normalizes query parameters", async () => {
+    const policy = urlQueryParamNormalizationPolicy();
+    const request = createPipelineRequest({
+      url: "https://example.azconfig.io/kv?api-version=2023-11-01&After=abcdefg&key=*&label=dev&$Select=key",
+    });
+    const response = await policy.sendRequest(request, mockNext());
+    const finalUrl = response.headers.get("url-lookup")!;
+    console.log(finalUrl);
+    expect(
+      finalUrl.endsWith("?%24select=key&after=abcdefg&api-version=2023-11-01&key=*&label=dev"),
+    ).toBe(true);
+  });
+});
diff --git a/sdk/appconfiguration/app-configuration/test/public/queryParam.spec.ts b/sdk/appconfiguration/app-configuration/test/public/queryParam.spec.ts
new file mode 100644
index 000000000000..36f420d7f2c3
--- /dev/null
+++ b/sdk/appconfiguration/app-configuration/test/public/queryParam.spec.ts
@@ -0,0 +1,159 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT License.
+
+import type {
+  AppConfigurationClient
+} from "../../src/index.js";
+import type { Recorder } from "@azure-tools/test-recorder";
+import { isLiveMode} from "@azure-tools/test-recorder";
+import type { PipelinePolicy } from "@azure/core-rest-pipeline";
+import {
+  createAppConfigurationClientForTests,
+  startRecorder,
+} from "./utils/testHelpers.js";
+import { describe, it, assert, beforeEach, afterEach } from "vitest";
+
+describe("request url query parameters", () => {
+  let recorder: Recorder;
+
+  beforeEach(async (ctx) => {
+    recorder = await startRecorder(ctx);
+  });
+
+  afterEach(async () => {
+    await recorder.stop();
+  });
+
+  describe("normalize query parameters", () => {
+    it("sort query params in alphabetical order", async () => {
+      const key = recorder.variable(
+        "sortQueryParams",
+        `sortQueryParams${Math.floor(Math.random() * 1000)}`,
+      );
+
+      const { getCapturedUrl, client } = createClientWithUrlCapturePolicy();
+
+      await client.addConfigurationSetting({ key, label: "dev", value: "some value" });
+
+      const configurationSetting = await client.getConfigurationSetting(
+        { key, label: "dev" },
+        { fields: ["key"] },
+      );
+
+      assert.ok(
+        getCapturedUrl(),
+        "Expected to have captured a request URL for getConfigurationSetting",
+      );
+      // Regex enforces exact ordering of query params: $select (or %24select), api-version, label
+      let queryOrderRegex = /\?(?:\$|%24)select=key&api-version=[^&]+&label=dev$/;
+      assert.match(
+        getCapturedUrl()!,
+        queryOrderRegex,
+        `Query parameters not in expected order or values. URL: ${getCapturedUrl()}`,
+      );
+
+      assert.equal(configurationSetting.key, key);
+
+      const listResult = client.listConfigurationSettings({ keyFilter: "*", labelFilter: "dev" });
+
+      for await (const _ of listResult.byPage()) {
+        // do nothing, just drain the iterator
+      }
+
+      // Regex enforces exact ordering of query params: api-version, key, label
+      queryOrderRegex = /\?api-version=[^&]+&key=\*&label=dev$/;
+      console.log("Captured URL for listConfigurationSettings:", getCapturedUrl());
+      assert.match(
+        getCapturedUrl()!,
+        queryOrderRegex,
+        `Query parameters not in expected order or values. URL: ${getCapturedUrl()}`,
+      );
+
+      await client.deleteConfigurationSetting({ key, label: "dev" });
+    });
+
+    // This occasionally hits 429 error (throttling) since we are making 100s of requests in the test to create, get and delete keys.
+    // To avoid hitting the service with too many requests, skipping the test in live.
+    // More details at https://github.com/Azure/azure-sdk-for-js/issues/16743
+    //
+    // Remove the following line if you want to hit the live service.
+    it("sort query params in alphabetical order - continuation token", /* { skip: isLiveMode() }, */ async () => {
+      const key = recorder.variable(
+        "sortQueryParamsMultiplePages",
+        `sortQueryParamsMultiplePages${Math.floor(Math.random() * 1000)}`,
+      );
+
+      const { getCapturedUrl, client } = createClientWithUrlCapturePolicy();
+
+      // this number is arbitrarily chosen to match the size of a page + 1
+      const expectedNumberOfLabels = 101;
+
+      let addSettingPromises = [];
+
+      for (let i = 0; i < expectedNumberOfLabels; i++) {
+        addSettingPromises.push(
+          client.addConfigurationSetting({
+            key,
+            value: `the value for ${i}`,
+            label: i.toString(),
+          }),
+        );
+
+        if (i !== 0 && i % 2 === 0) {
+          await Promise.all(addSettingPromises);
+          addSettingPromises = [];
+        }
+      }
+
+      const listResult = client.listConfigurationSettings({
+        keyFilter: key,
+      });
+
+      for await (const _ of listResult.byPage()) {
+        // do nothing, just drain the iterator
+      }
+
+        // Regex enforces exact ordering of query params for continuation page: after, api-version, key
+      // Note that only the request for the second page has the 'after' query param
+        const queryOrderRegex = new RegExp(
+          `\\?after=[^&]+&api-version=[^&]+&key=[^&]+$`,
+        );
+
+      assert.match(
+        getCapturedUrl()!,
+        queryOrderRegex,
+        `Query parameters not in expected order or values. URL: ${getCapturedUrl()}`,
+      );
+
+      for (let i = 0; i < expectedNumberOfLabels; i++) {
+        await client.deleteConfigurationSetting({ key, label: i.toString() });
+      }
+    });
+
+    function createClientWithUrlCapturePolicy(): {
+      getCapturedUrl: () => string | undefined;
+      client: AppConfigurationClient;
+    } {
+      let capturedUrl: string | undefined;
+      const urlCapturePolicy: PipelinePolicy = {
+        name: "UrlCapturePolicy",
+        async sendRequest(request, next) {
+          capturedUrl = request.url;
+          return next(request);
+        },
+      };
+
+      const client = createAppConfigurationClientForTests(
+        recorder.configureClientOptions({
+          additionalPolicies: [
+            {
+              policy: urlCapturePolicy,
+              position: "perRetry",
+            },
+          ],
+        }),
+      );
+      return { getCapturedUrl: () => capturedUrl, client };
+    }
+  });
+});

From bb14d1045777f06ec369cb472a172bac475290a1 Mon Sep 17 00:00:00 2001
From: Zhiyuan Liang <zhiyuanliang@microsoft.com>
Date: Wed, 17 Sep 2025 15:24:37 +0800
Subject: [PATCH 03/21] remove debug code

---
 .../app-configuration/test/internal/queryParamPolicy.spec.ts     | 1 -
 .../app-configuration/test/public/queryParam.spec.ts             | 1 -
 2 files changed, 2 deletions(-)

diff --git a/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts b/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts
index 109d9444358f..225f2e49f42e 100644
--- a/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts
+++ b/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts
@@ -24,7 +24,6 @@ describe("urlQueryParamsNormalizationPolicy", () => {
     });
     const response = await policy.sendRequest(request, mockNext());
     const finalUrl = response.headers.get("url-lookup")!;
-    console.log(finalUrl);
     expect(
       finalUrl.endsWith("?%24select=key&after=abcdefg&api-version=2023-11-01&key=*&label=dev"),
     ).toBe(true);
diff --git a/sdk/appconfiguration/app-configuration/test/public/queryParam.spec.ts b/sdk/appconfiguration/app-configuration/test/public/queryParam.spec.ts
index 36f420d7f2c3..883a1f347f5f 100644
--- a/sdk/appconfiguration/app-configuration/test/public/queryParam.spec.ts
+++ b/sdk/appconfiguration/app-configuration/test/public/queryParam.spec.ts
@@ -62,7 +62,6 @@ describe("request url query parameters", () => {
 
       // Regex enforces exact ordering of query params: api-version, key, label
       queryOrderRegex = /\?api-version=[^&]+&key=\*&label=dev$/;
-      console.log("Captured URL for listConfigurationSettings:", getCapturedUrl());
       assert.match(
         getCapturedUrl()!,
         queryOrderRegex,

From 042e19f6f85dde4ab8af4cf8ccab3eade155637b Mon Sep 17 00:00:00 2001
From: Zhiyuan Liang <zhiyuanliang@microsoft.com>
Date: Thu, 18 Sep 2025 11:21:49 +0800
Subject: [PATCH 04/21] update recording

---
 sdk/appconfiguration/app-configuration/assets.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sdk/appconfiguration/app-configuration/assets.json b/sdk/appconfiguration/app-configuration/assets.json
index f1c3e2cc87aa..190fbaa69a6e 100644
--- a/sdk/appconfiguration/app-configuration/assets.json
+++ b/sdk/appconfiguration/app-configuration/assets.json
@@ -2,5 +2,5 @@
   "AssetsRepo": "Azure/azure-sdk-assets",
   "AssetsRepoPrefixPath": "js",
   "TagPrefix": "js/appconfiguration/app-configuration",
-  "Tag": "js/appconfiguration/app-configuration_bdaf29d71a"
+  "Tag": "js/appconfiguration/app-configuration_8e762deb20"
 }

From a3c09926855b3b8b71c3380feefea69f8870a930 Mon Sep 17 00:00:00 2001
From: Zhiyuan Liang <zhiyuanliang@microsoft.com>
Date: Thu, 18 Sep 2025 11:35:36 +0800
Subject: [PATCH 05/21] fix format

---
 .../test/public/queryParam.spec.ts            | 93 +++++++++----------
 1 file changed, 45 insertions(+), 48 deletions(-)

diff --git a/sdk/appconfiguration/app-configuration/test/public/queryParam.spec.ts b/sdk/appconfiguration/app-configuration/test/public/queryParam.spec.ts
index 883a1f347f5f..cee3d3224f85 100644
--- a/sdk/appconfiguration/app-configuration/test/public/queryParam.spec.ts
+++ b/sdk/appconfiguration/app-configuration/test/public/queryParam.spec.ts
@@ -1,16 +1,11 @@
 // Copyright (c) Microsoft Corporation.
 // Licensed under the MIT License.
 
-import type {
-  AppConfigurationClient
-} from "../../src/index.js";
+import type { AppConfigurationClient } from "../../src/index.js";
 import type { Recorder } from "@azure-tools/test-recorder";
-import { isLiveMode} from "@azure-tools/test-recorder";
+import { isLiveMode } from "@azure-tools/test-recorder";
 import type { PipelinePolicy } from "@azure/core-rest-pipeline";
-import {
-  createAppConfigurationClientForTests,
-  startRecorder,
-} from "./utils/testHelpers.js";
+import { createAppConfigurationClientForTests, startRecorder } from "./utils/testHelpers.js";
 import { describe, it, assert, beforeEach, afterEach } from "vitest";
 
 describe("request url query parameters", () => {
@@ -76,58 +71,60 @@ describe("request url query parameters", () => {
     // More details at https://github.com/Azure/azure-sdk-for-js/issues/16743
     //
     // Remove the following line if you want to hit the live service.
-    it("sort query params in alphabetical order - continuation token", /* { skip: isLiveMode() }, */ async () => {
-      const key = recorder.variable(
-        "sortQueryParamsMultiplePages",
-        `sortQueryParamsMultiplePages${Math.floor(Math.random() * 1000)}`,
-      );
+    it(
+      "sort query params in alphabetical order - continuation token",
+      { skip: isLiveMode() },
+      async () => {
+        const key = recorder.variable(
+          "sortQueryParamsMultiplePages",
+          `sortQueryParamsMultiplePages${Math.floor(Math.random() * 1000)}`,
+        );
 
-      const { getCapturedUrl, client } = createClientWithUrlCapturePolicy();
+        const { getCapturedUrl, client } = createClientWithUrlCapturePolicy();
 
-      // this number is arbitrarily chosen to match the size of a page + 1
-      const expectedNumberOfLabels = 101;
+        // this number is arbitrarily chosen to match the size of a page + 1
+        const expectedNumberOfLabels = 101;
 
-      let addSettingPromises = [];
+        let addSettingPromises = [];
 
-      for (let i = 0; i < expectedNumberOfLabels; i++) {
-        addSettingPromises.push(
-          client.addConfigurationSetting({
-            key,
-            value: `the value for ${i}`,
-            label: i.toString(),
-          }),
-        );
+        for (let i = 0; i < expectedNumberOfLabels; i++) {
+          addSettingPromises.push(
+            client.addConfigurationSetting({
+              key,
+              value: `the value for ${i}`,
+              label: i.toString(),
+            }),
+          );
 
-        if (i !== 0 && i % 2 === 0) {
-          await Promise.all(addSettingPromises);
-          addSettingPromises = [];
+          if (i !== 0 && i % 2 === 0) {
+            await Promise.all(addSettingPromises);
+            addSettingPromises = [];
+          }
         }
-      }
 
-      const listResult = client.listConfigurationSettings({
-        keyFilter: key,
-      });
+        const listResult = client.listConfigurationSettings({
+          keyFilter: key,
+        });
 
-      for await (const _ of listResult.byPage()) {
-        // do nothing, just drain the iterator
-      }
+        for await (const _ of listResult.byPage()) {
+          // do nothing, just drain the iterator
+        }
 
         // Regex enforces exact ordering of query params for continuation page: after, api-version, key
-      // Note that only the request for the second page has the 'after' query param
-        const queryOrderRegex = new RegExp(
-          `\\?after=[^&]+&api-version=[^&]+&key=[^&]+$`,
-        );
+        // Note that only the request for the second page has the 'after' query param
+        const queryOrderRegex = new RegExp(`\\?after=[^&]+&api-version=[^&]+&key=[^&]+$`);
 
-      assert.match(
-        getCapturedUrl()!,
-        queryOrderRegex,
-        `Query parameters not in expected order or values. URL: ${getCapturedUrl()}`,
-      );
+        assert.match(
+          getCapturedUrl()!,
+          queryOrderRegex,
+          `Query parameters not in expected order or values. URL: ${getCapturedUrl()}`,
+        );
 
-      for (let i = 0; i < expectedNumberOfLabels; i++) {
-        await client.deleteConfigurationSetting({ key, label: i.toString() });
-      }
-    });
+        for (let i = 0; i < expectedNumberOfLabels; i++) {
+          await client.deleteConfigurationSetting({ key, label: i.toString() });
+        }
+      },
+    );
 
     function createClientWithUrlCapturePolicy(): {
       getCapturedUrl: () => string | undefined;

From b0f8ce2844b96005e16f850d916b46e31370ecf4 Mon Sep 17 00:00:00 2001
From: Zhiyuan Liang <zhiyuanliang@microsoft.com>
Date: Thu, 18 Sep 2025 14:24:43 +0800
Subject: [PATCH 06/21] update

---
 .../app-configuration/src/internal/queryParamPolicy.ts          | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts b/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts
index f88bb953432e..62f39ed419a6 100644
--- a/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts
+++ b/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts
@@ -37,7 +37,7 @@ export function urlQueryParamNormalizationPolicy(): PipelinePolicy {
       for (const p of collected) {
         normalized.append(p.lower, p.value);
       }
-      Object.assign(request, { url: `${base}?${normalized.toString()}` });
+      request.url = `${base}?${normalized.toString()}`;
       return next(request);
     },
   };

From 387d730bb4bb62875352435c8031370d1226caab Mon Sep 17 00:00:00 2001
From: Zhiyuan Liang <zhiyuanliang@microsoft.com>
Date: Thu, 25 Sep 2025 17:32:12 +0800
Subject: [PATCH 07/21] add test for tag query

---
 .../app-configuration/assets.json             |  2 +-
 .../src/appConfigurationClient.ts             |  4 ++--
 .../src/internal/queryParamPolicy.ts          |  2 +-
 .../test/internal/queryParamPolicy.spec.ts    |  4 ++--
 .../test/public/queryParam.spec.ts            | 21 ++++++++++++++++++-
 5 files changed, 26 insertions(+), 7 deletions(-)

diff --git a/sdk/appconfiguration/app-configuration/assets.json b/sdk/appconfiguration/app-configuration/assets.json
index 190fbaa69a6e..2f592c8dc5c8 100644
--- a/sdk/appconfiguration/app-configuration/assets.json
+++ b/sdk/appconfiguration/app-configuration/assets.json
@@ -2,5 +2,5 @@
   "AssetsRepo": "Azure/azure-sdk-assets",
   "AssetsRepoPrefixPath": "js",
   "TagPrefix": "js/appconfiguration/app-configuration",
-  "Tag": "js/appconfiguration/app-configuration_8e762deb20"
+  "Tag": "js/appconfiguration/app-configuration_8382357163"
 }
diff --git a/sdk/appconfiguration/app-configuration/src/appConfigurationClient.ts b/sdk/appconfiguration/app-configuration/src/appConfigurationClient.ts
index 6f512edcd7a3..be1937b3bf1f 100644
--- a/sdk/appconfiguration/app-configuration/src/appConfigurationClient.ts
+++ b/sdk/appconfiguration/app-configuration/src/appConfigurationClient.ts
@@ -57,7 +57,7 @@ import { getPagedAsyncIterator } from "@azure/core-paging";
 import type { PipelinePolicy, RestError } from "@azure/core-rest-pipeline";
 import { bearerTokenAuthenticationPolicy } from "@azure/core-rest-pipeline";
 import { SyncTokens, syncTokenPolicy } from "./internal/syncTokenPolicy.js";
-import { urlQueryParamNormalizationPolicy } from "./internal/queryParamPolicy.js";
+import { queryParamPolicy } from "./internal/queryParamPolicy.js";
 import type { TokenCredential } from "@azure/core-auth";
 import { isTokenCredential } from "@azure/core-auth";
 import type {
@@ -196,7 +196,7 @@ export class AppConfigurationClient {
       internalClientPipelineOptions,
     );
     this.client.pipeline.addPolicy(authPolicy, { phase: "Sign" });
-    this.client.pipeline.addPolicy(urlQueryParamNormalizationPolicy());
+    this.client.pipeline.addPolicy(queryParamPolicy());
     this.client.pipeline.addPolicy(syncTokenPolicy(this._syncTokens), { afterPhase: "Retry" });
   }
 
diff --git a/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts b/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts
index 62f39ed419a6..de9a3384192d 100644
--- a/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts
+++ b/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts
@@ -14,7 +14,7 @@ import type { PipelinePolicy } from "@azure/core-rest-pipeline";
  * NOTE: Only enable if the target service treats parameter names case-insensitively.
  * @internal
  */
-export function urlQueryParamNormalizationPolicy(): PipelinePolicy {
+export function queryParamPolicy(): PipelinePolicy {
   return {
     name: "urlQueryParamNormalizationPolicy",
     async sendRequest(request, next) {
diff --git a/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts b/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts
index 225f2e49f42e..3c31776eec62 100644
--- a/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts
+++ b/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts
@@ -2,7 +2,7 @@
 // Licensed under the MIT License.
 
 import { describe, it, expect } from "vitest";
-import { urlQueryParamNormalizationPolicy } from "../../src/internal/queryParamPolicy.js";
+import { queryParamPolicy } from "../../src/internal/queryParamPolicy.js";
 import { createPipelineRequest, createHttpHeaders } from "@azure/core-rest-pipeline";
 import type { PipelineRequest, PipelineResponse } from "@azure/core-rest-pipeline";
 
@@ -18,7 +18,7 @@ function mockNext(returnStatus: number = 200) {
 
 describe("urlQueryParamsNormalizationPolicy", () => {
   it("normalizes query parameters", async () => {
-    const policy = urlQueryParamNormalizationPolicy();
+    const policy = queryParamPolicy();
     const request = createPipelineRequest({
       url: "https://example.azconfig.io/kv?api-version=2023-11-01&After=abcdefg&key=*&label=dev&$Select=key",
     });
diff --git a/sdk/appconfiguration/app-configuration/test/public/queryParam.spec.ts b/sdk/appconfiguration/app-configuration/test/public/queryParam.spec.ts
index cee3d3224f85..4f51f4552124 100644
--- a/sdk/appconfiguration/app-configuration/test/public/queryParam.spec.ts
+++ b/sdk/appconfiguration/app-configuration/test/public/queryParam.spec.ts
@@ -28,7 +28,12 @@ describe("request url query parameters", () => {
 
       const { getCapturedUrl, client } = createClientWithUrlCapturePolicy();
 
-      await client.addConfigurationSetting({ key, label: "dev", value: "some value" });
+      await client.addConfigurationSetting({
+        key,
+        label: "dev",
+        value: "some value",
+        tags: { tag1: "value1" }
+      });
 
       const configurationSetting = await client.getConfigurationSetting(
         { key, label: "dev" },
@@ -63,6 +68,20 @@ describe("request url query parameters", () => {
         `Query parameters not in expected order or values. URL: ${getCapturedUrl()}`,
       );
 
+      const listWithTagsResult = client.listConfigurationSettings({ keyFilter: "*", labelFilter: "dev", tagsFilter: ["tag1=value1", "tag1=value1"]});
+
+      for await (const _ of listWithTagsResult.byPage()) {
+        // do nothing, just drain the iterator
+      }
+
+      // Regex enforces exact ordering of query params: api-version, key, label, tags
+      queryOrderRegex = /\?api-version=[^&]+&key=\*&label=dev&tags=tag1%3Dvalue1&tags=tag1%3Dvalue1$/;
+      assert.match(
+        getCapturedUrl()!,
+        queryOrderRegex,
+        `Query parameters not in expected order or values. URL: ${getCapturedUrl()}`,
+      );
+
       await client.deleteConfigurationSetting({ key, label: "dev" });
     });
 

From 1bd5a4e7c8645e0dcb73f1a0b0716690b24c962c Mon Sep 17 00:00:00 2001
From: Zhiyuan Liang <zhiyuanliang@microsoft.com>
Date: Mon, 29 Sep 2025 17:27:38 +0800
Subject: [PATCH 08/21] update

---
 .../src/internal/queryParamPolicy.ts          | 101 ++++++++++++------
 .../test/internal/queryParamPolicy.spec.ts    |   4 +-
 .../test/public/queryParam.spec.ts            |  11 +-
 3 files changed, 80 insertions(+), 36 deletions(-)

diff --git a/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts b/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts
index de9a3384192d..525f11e7fffa 100644
--- a/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts
+++ b/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts
@@ -1,44 +1,83 @@
 // Copyright (c) Microsoft Corporation.
 // Licensed under the MIT License.
 
-import type { PipelinePolicy } from "@azure/core-rest-pipeline";
+import type {
+  PipelinePolicy,
+  PipelineRequest,
+  PipelineResponse,
+  SendRequest
+} from "@azure/core-rest-pipeline";
 
 /**
- * A policy that normalizes query parameters for stable, canonical request URLs.
- * Behavior:
- * 1. All query parameter names are converted to lowercase (canonical form).
- * 2. Parameters are sorted lexicographically by their lowercase names.
- * 3. Relative order of duplicate names (ignoring case) is preserved (stable sort guarantee).
- *
- * This improves determinism for recordings and avoids casing-related cache misses.
- * NOTE: Only enable if the target service treats parameter names case-insensitively.
- * @internal
+ * Creates a PipelinePolicy that normalizes query parameters:
+ *  - Lowercase names
+ *  - Sort by lowercase name
+ *  - Preserve the relative order of duplicates
+ *  - Do not percent-encode values; keep original text
  */
 export function queryParamPolicy(): PipelinePolicy {
   return {
-    name: "urlQueryParamNormalizationPolicy",
-    async sendRequest(request, next) {
-      const qIndex = request.url.indexOf("?");
-      if (qIndex === -1) {
-        return next(request);
-      }
+    name: "normalizeQueryPolicy",
+    async sendRequest(request: PipelineRequest, next: SendRequest): Promise<PipelineResponse> {
+      try {
+        const originalUrl = request.url;
 
-      const base = request.url.substring(0, qIndex);
-      const queryString = request.url.substring(qIndex + 1);
-      const params = new URLSearchParams(queryString);
-      const collected: Array<{ name: string; value: string; lower: string }> = [];
-      for (const [name, value] of params.entries()) {
-        collected.push({ name, value, lower: name.toLowerCase() });
-      }
-      if (collected.length > 1) {
-        collected.sort((a, b) => (a.lower < b.lower ? -1 : a.lower > b.lower ? 1 : 0));
-      }
-      const normalized = new URLSearchParams();
-      for (const p of collected) {
-        normalized.append(p.lower, p.value);
+        // Separate out any hash fragment so we can keep it verbatim.
+        const hashIndex = originalUrl.indexOf("#");
+        const beforeHash = hashIndex >= 0 ? originalUrl.slice(0, hashIndex) : originalUrl;
+        const hashFrag = hashIndex >= 0 ? originalUrl.slice(hashIndex) : "";
+
+        const qIndex = beforeHash.indexOf("?");
+        if (qIndex < 0) {
+          return next(request);
+        }
+
+        // We don't use URLSearchParams because it will do percent-encoding.
+        // https://developer.mozilla.org/en-US/docs/Web/API/URLSearchParams#percent_encoding
+        const base = beforeHash.slice(0, qIndex);
+        const queryString = beforeHash.slice(qIndex + 1);
+        const segments = queryString.split("&").filter((s) => s.length > 0);
+
+        type Entry = {
+          rawName: string;
+          lowerName: string;
+          value: string | undefined;
+          index: number;
+        };
+
+        const entries: Entry[] = segments.map((seg, i) => {
+          const eq = seg.indexOf("=");
+          const rawName = eq === -1 ? seg : seg.slice(0, eq);
+          const value = eq === -1 ? undefined : seg.slice(eq + 1);
+          return {
+            rawName,
+            lowerName: rawName.toLowerCase(),
+            value,
+            index: i
+          };
+        });
+
+        entries.sort((a, b) => {
+          if (a.lowerName < b.lowerName) return -1;
+          if (a.lowerName > b.lowerName) return 1;
+          return a.index - b.index; // stability for duplicates
+        });
+
+        const normalizedQuery = entries
+          .map((e) => (e.value !== undefined ? `${e.lowerName}=${e.value}` : e.lowerName))
+          .join("&");
+
+        const newUrl = `${base}${normalizedQuery ? "?" + normalizedQuery : ""}${hashFrag}`;
+
+        // Only update if changed (optional, but nice to avoid surprising downstream logic).
+        if (newUrl !== originalUrl) {
+          request.url = newUrl;
+        }
+      } catch {
+        // If anything goes wrong, fall back to sending the original request.
       }
-      request.url = `${base}?${normalized.toString()}`;
+
       return next(request);
-    },
+    }
   };
 }
diff --git a/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts b/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts
index 3c31776eec62..f7f32584681e 100644
--- a/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts
+++ b/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts
@@ -20,12 +20,12 @@ describe("urlQueryParamsNormalizationPolicy", () => {
   it("normalizes query parameters", async () => {
     const policy = queryParamPolicy();
     const request = createPipelineRequest({
-      url: "https://example.azconfig.io/kv?api-version=2023-11-01&After=abcdefg&key=*&label=dev&$Select=key",
+      url: "https://example.azconfig.io/kv?api-version=2023-11-01&After=abcdefg&tags=tag3%3Dvalue3&key=*&label=dev&$Select=key&tags=tag2%3Dvalue2&tags=tag1%3Dvalue1",
     });
     const response = await policy.sendRequest(request, mockNext());
     const finalUrl = response.headers.get("url-lookup")!;
     expect(
-      finalUrl.endsWith("?%24select=key&after=abcdefg&api-version=2023-11-01&key=*&label=dev"),
+      finalUrl.endsWith("?$select=key&after=abcdefg&api-version=2023-11-01&key=*&label=dev&tags=tag3%3Dvalue3&tags=tag2%3Dvalue2&tags=tag1%3Dvalue1"),
     ).toBe(true);
   });
 });
diff --git a/sdk/appconfiguration/app-configuration/test/public/queryParam.spec.ts b/sdk/appconfiguration/app-configuration/test/public/queryParam.spec.ts
index 4f51f4552124..6b991c4e145a 100644
--- a/sdk/appconfiguration/app-configuration/test/public/queryParam.spec.ts
+++ b/sdk/appconfiguration/app-configuration/test/public/queryParam.spec.ts
@@ -32,7 +32,7 @@ describe("request url query parameters", () => {
         key,
         label: "dev",
         value: "some value",
-        tags: { tag1: "value1" }
+        tags: { tag1: "value1" },
       });
 
       const configurationSetting = await client.getConfigurationSetting(
@@ -68,14 +68,19 @@ describe("request url query parameters", () => {
         `Query parameters not in expected order or values. URL: ${getCapturedUrl()}`,
       );
 
-      const listWithTagsResult = client.listConfigurationSettings({ keyFilter: "*", labelFilter: "dev", tagsFilter: ["tag1=value1", "tag1=value1"]});
+      const listWithTagsResult = client.listConfigurationSettings({
+        keyFilter: "*",
+        labelFilter: "dev",
+        tagsFilter: ["tag2=value2", "tag1=value1", "tag3=value3"],
+      });
 
       for await (const _ of listWithTagsResult.byPage()) {
         // do nothing, just drain the iterator
       }
 
       // Regex enforces exact ordering of query params: api-version, key, label, tags
-      queryOrderRegex = /\?api-version=[^&]+&key=\*&label=dev&tags=tag1%3Dvalue1&tags=tag1%3Dvalue1$/;
+      queryOrderRegex =
+        /\?api-version=[^&]+&key=\*&label=dev&tags=tag2%3Dvalue2&tags=tag1%3Dvalue1&tags=tag3%3Dvalue3$/;
       assert.match(
         getCapturedUrl()!,
         queryOrderRegex,

From 857c8493a210cebac7d59aa1b0add5accfb180ee Mon Sep 17 00:00:00 2001
From: Zhiyuan Liang <zhiyuanliang@microsoft.com>
Date: Mon, 29 Sep 2025 17:45:34 +0800
Subject: [PATCH 09/21] update

---
 sdk/appconfiguration/app-configuration/assets.json          | 2 +-
 .../app-configuration/src/internal/queryParamPolicy.ts      | 6 +++---
 .../test/internal/queryParamPolicy.spec.ts                  | 4 +++-
 3 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/sdk/appconfiguration/app-configuration/assets.json b/sdk/appconfiguration/app-configuration/assets.json
index 2f592c8dc5c8..085e3044ecf7 100644
--- a/sdk/appconfiguration/app-configuration/assets.json
+++ b/sdk/appconfiguration/app-configuration/assets.json
@@ -2,5 +2,5 @@
   "AssetsRepo": "Azure/azure-sdk-assets",
   "AssetsRepoPrefixPath": "js",
   "TagPrefix": "js/appconfiguration/app-configuration",
-  "Tag": "js/appconfiguration/app-configuration_8382357163"
+  "Tag": "js/appconfiguration/app-configuration_55c63bcf25"
 }
diff --git a/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts b/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts
index 525f11e7fffa..1b1d49b4a653 100644
--- a/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts
+++ b/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts
@@ -5,7 +5,7 @@ import type {
   PipelinePolicy,
   PipelineRequest,
   PipelineResponse,
-  SendRequest
+  SendRequest,
 } from "@azure/core-rest-pipeline";
 
 /**
@@ -53,7 +53,7 @@ export function queryParamPolicy(): PipelinePolicy {
             rawName,
             lowerName: rawName.toLowerCase(),
             value,
-            index: i
+            index: i,
           };
         });
 
@@ -78,6 +78,6 @@ export function queryParamPolicy(): PipelinePolicy {
       }
 
       return next(request);
-    }
+    },
   };
 }
diff --git a/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts b/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts
index f7f32584681e..c301c4b818ac 100644
--- a/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts
+++ b/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts
@@ -25,7 +25,9 @@ describe("urlQueryParamsNormalizationPolicy", () => {
     const response = await policy.sendRequest(request, mockNext());
     const finalUrl = response.headers.get("url-lookup")!;
     expect(
-      finalUrl.endsWith("?$select=key&after=abcdefg&api-version=2023-11-01&key=*&label=dev&tags=tag3%3Dvalue3&tags=tag2%3Dvalue2&tags=tag1%3Dvalue1"),
+      finalUrl.endsWith(
+        "?$select=key&after=abcdefg&api-version=2023-11-01&key=*&label=dev&tags=tag3%3Dvalue3&tags=tag2%3Dvalue2&tags=tag1%3Dvalue1",
+      ),
     ).toBe(true);
   });
 });

From 6376b8cd0f82cb70b5f6ed5307a5f0208f6bd201 Mon Sep 17 00:00:00 2001
From: Zhiyuan Liang <zhiyuanliang@microsoft.com>
Date: Fri, 10 Oct 2025 14:20:56 +0800
Subject: [PATCH 10/21] update

---
 .../src/internal/queryParamPolicy.ts          | 83 +++++++++----------
 .../test/internal/queryParamPolicy.spec.ts    | 40 +++++++++
 2 files changed, 79 insertions(+), 44 deletions(-)

diff --git a/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts b/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts
index 1b1d49b4a653..d5f6c2451c59 100644
--- a/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts
+++ b/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts
@@ -17,62 +17,52 @@ import type {
  */
 export function queryParamPolicy(): PipelinePolicy {
   return {
-    name: "normalizeQueryPolicy",
+    name: "queryParamPolicy",
     async sendRequest(request: PipelineRequest, next: SendRequest): Promise<PipelineResponse> {
       try {
         const originalUrl = request.url;
 
-        // Separate out any hash fragment so we can keep it verbatim.
-        const hashIndex = originalUrl.indexOf("#");
-        const beforeHash = hashIndex >= 0 ? originalUrl.slice(0, hashIndex) : originalUrl;
-        const hashFrag = hashIndex >= 0 ? originalUrl.slice(hashIndex) : "";
+        // Use URL API to decompose parts
+        const url = new URL(originalUrl);
 
-        const qIndex = beforeHash.indexOf("?");
-        if (qIndex < 0) {
+        if (url.search === "") {
           return next(request);
         }
 
-        // We don't use URLSearchParams because it will do percent-encoding.
-        // https://developer.mozilla.org/en-US/docs/Web/API/URLSearchParams#percent_encoding
-        const base = beforeHash.slice(0, qIndex);
-        const queryString = beforeHash.slice(qIndex + 1);
-        const segments = queryString.split("&").filter((s) => s.length > 0);
+        const search: string = url.search.slice(1); // Remove leading '?'
+        // We don't use URLSearchParams because it doesn't distinguish ?param= and ?param.
+        const rawParams = search.split("&").filter((value) => value !== "");
 
-        type Entry = {
-          rawName: string;
-          lowerName: string;
-          value: string | undefined;
-          index: number;
-        };
-
-        const entries: Entry[] = segments.map((seg, i) => {
-          const eq = seg.indexOf("=");
-          const rawName = eq === -1 ? seg : seg.slice(0, eq);
-          const value = eq === -1 ? undefined : seg.slice(eq + 1);
-          return {
-            rawName,
-            lowerName: rawName.toLowerCase(),
-            value,
-            index: i,
-          };
-        });
+        const params: ParamEntry[] = [];
+        for (const p of rawParams) {
+          const eq = p.indexOf("=");
+          if (eq >= 0) {
+            params.push({
+              lowercaseName: p.substring(0, eq).toLowerCase(),
+              value: p.substring(eq), // Keep the '='
+            });
+          } else {
+            params.push({
+              lowercaseName: p.toLowerCase(),
+              value: "",
+            });
+          }
+        }
 
-        entries.sort((a, b) => {
-          if (a.lowerName < b.lowerName) return -1;
-          if (a.lowerName > b.lowerName) return 1;
-          return a.index - b.index; // stability for duplicates
+        // Modern JavaScript Array.prototype.sort is stable
+        // https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/sort#sort_stability
+        params.sort((a, b) => {
+          if (a.lowercaseName < b.lowercaseName) {
+            return -1;
+          } else if (a.lowercaseName > b.lowercaseName) {
+            return 1;
+          }
+          return 0;
         });
 
-        const normalizedQuery = entries
-          .map((e) => (e.value !== undefined ? `${e.lowerName}=${e.value}` : e.lowerName))
-          .join("&");
-
-        const newUrl = `${base}${normalizedQuery ? "?" + normalizedQuery : ""}${hashFrag}`;
-
-        // Only update if changed (optional, but nice to avoid surprising downstream logic).
-        if (newUrl !== originalUrl) {
-          request.url = newUrl;
-        }
+        const newSearch = params.map((p) => p.lowercaseName + p.value).join("&");
+        const newUrl = url.origin + url.pathname + "?" + newSearch + url.hash;
+        request.url = newUrl;
       } catch {
         // If anything goes wrong, fall back to sending the original request.
       }
@@ -81,3 +71,8 @@ export function queryParamPolicy(): PipelinePolicy {
     },
   };
 }
+
+interface ParamEntry {
+  lowercaseName: string;
+  value: string;
+}
diff --git a/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts b/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts
index c301c4b818ac..2e81f77fa393 100644
--- a/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts
+++ b/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts
@@ -30,4 +30,44 @@ describe("urlQueryParamsNormalizationPolicy", () => {
       ),
     ).toBe(true);
   });
+
+  it("keeps original order of query parameters", async () => {
+    const policy = queryParamPolicy();
+    const request = createPipelineRequest({
+      url: "https://example.azconfig.io/kv?tags=tag2&api-version=2023-11-01&tags=tag1",
+    });
+    const response = await policy.sendRequest(request, mockNext());
+    const finalUrl = response.headers.get("url-lookup")!;
+    expect(finalUrl.endsWith("?api-version=2023-11-01&tags=tag2&tags=tag1")).toBe(true);
+  });
+
+  it("does not percent-encode values", async () => {
+    const policy = queryParamPolicy();
+    const request = createPipelineRequest({
+      url: "https://example.azconfig.io/kv?tags=tag=value&==",
+    });
+    const response = await policy.sendRequest(request, mockNext());
+    const finalUrl = response.headers.get("url-lookup")!;
+    expect(finalUrl.endsWith("?==&tags=tag=value")).toBe(true);
+  });
+
+  it("keeps key with no value", async () => {
+    const policy = queryParamPolicy();
+    const request = createPipelineRequest({
+      url: "https://example.azconfig.io/kv?tags&api-version=2023-11-01",
+    });
+    const response = await policy.sendRequest(request, mockNext());
+    const finalUrl = response.headers.get("url-lookup")!;
+    expect(finalUrl.endsWith("?api-version=2023-11-01&tags")).toBe(true);
+  });
+
+  it("removes redundant &", async () => {
+    const policy = queryParamPolicy();
+    const request = createPipelineRequest({
+      url: "https://example.azconfig.io/kv?&&&",
+    });
+    const response = await policy.sendRequest(request, mockNext());
+    const finalUrl = response.headers.get("url-lookup")!;
+    expect(finalUrl.endsWith("?")).toBe(true);
+  });
 });

From a68e541de14f1e9c7483c0fcacc9e80dc1fd1727 Mon Sep 17 00:00:00 2001
From: Zhiyuan Liang <zhiyuanliang@microsoft.com>
Date: Wed, 15 Oct 2025 14:57:39 +0800
Subject: [PATCH 11/21] update

---
 .../src/internal/queryParamPolicy.ts          | 37 +++++++------------
 .../test/internal/queryParamPolicy.spec.ts    | 15 ++------
 2 files changed, 16 insertions(+), 36 deletions(-)

diff --git a/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts b/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts
index d5f6c2451c59..3148805258de 100644
--- a/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts
+++ b/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts
@@ -13,40 +13,22 @@ import type {
  *  - Lowercase names
  *  - Sort by lowercase name
  *  - Preserve the relative order of duplicates
- *  - Do not percent-encode values; keep original text
  */
 export function queryParamPolicy(): PipelinePolicy {
   return {
     name: "queryParamPolicy",
     async sendRequest(request: PipelineRequest, next: SendRequest): Promise<PipelineResponse> {
       try {
-        const originalUrl = request.url;
-
-        // Use URL API to decompose parts
+        const originalUrl: string = request.url;
         const url = new URL(originalUrl);
 
         if (url.search === "") {
           return next(request);
         }
 
-        const search: string = url.search.slice(1); // Remove leading '?'
-        // We don't use URLSearchParams because it doesn't distinguish ?param= and ?param.
-        const rawParams = search.split("&").filter((value) => value !== "");
-
         const params: ParamEntry[] = [];
-        for (const p of rawParams) {
-          const eq = p.indexOf("=");
-          if (eq >= 0) {
-            params.push({
-              lowercaseName: p.substring(0, eq).toLowerCase(),
-              value: p.substring(eq), // Keep the '='
-            });
-          } else {
-            params.push({
-              lowercaseName: p.toLowerCase(),
-              value: "",
-            });
-          }
+        for (const [name, value] of url.searchParams.entries()) {
+          params.push({ lowercaseName: name.toLowerCase(), value });
         }
 
         // Modern JavaScript Array.prototype.sort is stable
@@ -60,11 +42,18 @@ export function queryParamPolicy(): PipelinePolicy {
           return 0;
         });
 
-        const newSearch = params.map((p) => p.lowercaseName + p.value).join("&");
-        const newUrl = url.origin + url.pathname + "?" + newSearch + url.hash;
-        request.url = newUrl;
+        const newSearchParams = new URLSearchParams();
+        for (const p of params) {
+          newSearchParams.append(p.lowercaseName, p.value);
+        }
+
+        const newUrl = url.origin + url.pathname + "?" + newSearchParams.toString() + url.hash;
+        if (newUrl !== originalUrl) {
+          request.url = newUrl;
+        }
       } catch {
         // If anything goes wrong, fall back to sending the original request.
+        console.log("Failed to normalize query parameters.");
       }
 
       return next(request);
diff --git a/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts b/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts
index 2e81f77fa393..45f0e4aa1a0f 100644
--- a/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts
+++ b/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts
@@ -24,9 +24,10 @@ describe("urlQueryParamsNormalizationPolicy", () => {
     });
     const response = await policy.sendRequest(request, mockNext());
     const finalUrl = response.headers.get("url-lookup")!;
+    console.log(finalUrl);
     expect(
       finalUrl.endsWith(
-        "?$select=key&after=abcdefg&api-version=2023-11-01&key=*&label=dev&tags=tag3%3Dvalue3&tags=tag2%3Dvalue2&tags=tag1%3Dvalue1",
+        "?%24select=key&after=abcdefg&api-version=2023-11-01&key=*&label=dev&tags=tag3%3Dvalue3&tags=tag2%3Dvalue2&tags=tag1%3Dvalue1",
       ),
     ).toBe(true);
   });
@@ -41,16 +42,6 @@ describe("urlQueryParamsNormalizationPolicy", () => {
     expect(finalUrl.endsWith("?api-version=2023-11-01&tags=tag2&tags=tag1")).toBe(true);
   });
 
-  it("does not percent-encode values", async () => {
-    const policy = queryParamPolicy();
-    const request = createPipelineRequest({
-      url: "https://example.azconfig.io/kv?tags=tag=value&==",
-    });
-    const response = await policy.sendRequest(request, mockNext());
-    const finalUrl = response.headers.get("url-lookup")!;
-    expect(finalUrl.endsWith("?==&tags=tag=value")).toBe(true);
-  });
-
   it("keeps key with no value", async () => {
     const policy = queryParamPolicy();
     const request = createPipelineRequest({
@@ -58,7 +49,7 @@ describe("urlQueryParamsNormalizationPolicy", () => {
     });
     const response = await policy.sendRequest(request, mockNext());
     const finalUrl = response.headers.get("url-lookup")!;
-    expect(finalUrl.endsWith("?api-version=2023-11-01&tags")).toBe(true);
+    expect(finalUrl.endsWith("?api-version=2023-11-01&tags=")).toBe(true);
   });
 
   it("removes redundant &", async () => {

From 3f0635812ebc8cd20389873167fc898b0f64def4 Mon Sep 17 00:00:00 2001
From: Zhiyuan Liang <zhiyuanliang@microsoft.com>
Date: Thu, 23 Oct 2025 11:37:21 +0800
Subject: [PATCH 12/21] update

---
 .../src/internal/queryParamPolicy.ts                 | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts b/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts
index 3148805258de..a72b471c906a 100644
--- a/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts
+++ b/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts
@@ -27,7 +27,8 @@ export function queryParamPolicy(): PipelinePolicy {
         }
 
         const params: ParamEntry[] = [];
-        for (const [name, value] of url.searchParams.entries()) {
+        for (const entry of url.search.substring(1).split("&")) {
+          const [name, value] = entry.split("=", 1);
           params.push({ lowercaseName: name.toLowerCase(), value });
         }
 
@@ -42,12 +43,11 @@ export function queryParamPolicy(): PipelinePolicy {
           return 0;
         });
 
-        const newSearchParams = new URLSearchParams();
-        for (const p of params) {
-          newSearchParams.append(p.lowercaseName, p.value);
-        }
+        const newSearchParams = params
+          .map(({ lowercaseName, value }) => `${lowercaseName}=${value}`)
+          .join("&");
 
-        const newUrl = url.origin + url.pathname + "?" + newSearchParams.toString() + url.hash;
+        const newUrl = url.origin + url.pathname + "?" + newSearchParams + url.hash;
         if (newUrl !== originalUrl) {
           request.url = newUrl;
         }

From b461666d4e7fc0d7521c90af9f32483d83bd6572 Mon Sep 17 00:00:00 2001
From: Zhiyuan Liang <zhiyuanliang@microsoft.com>
Date: Thu, 23 Oct 2025 13:17:05 +0800
Subject: [PATCH 13/21] update

---
 .../src/internal/queryParamPolicy.ts          |  2 +-
 .../test/internal/queryParamPolicy.spec.ts    | 22 +------------------
 2 files changed, 2 insertions(+), 22 deletions(-)

diff --git a/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts b/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts
index a72b471c906a..c463af05930b 100644
--- a/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts
+++ b/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts
@@ -28,7 +28,7 @@ export function queryParamPolicy(): PipelinePolicy {
 
         const params: ParamEntry[] = [];
         for (const entry of url.search.substring(1).split("&")) {
-          const [name, value] = entry.split("=", 1);
+          const [name, value] = entry.split("=", 2);
           params.push({ lowercaseName: name.toLowerCase(), value });
         }
 
diff --git a/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts b/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts
index 57606d8109ef..4bdb79d2871d 100644
--- a/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts
+++ b/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts
@@ -26,7 +26,7 @@ describe("urlQueryParamsNormalizationPolicy", () => {
     const finalUrl = response.headers.get("url-lookup")!;
     expect(
       finalUrl.endsWith(
-        "?%24select=key&after=abcdefg&api-version=2023-11-01&key=*&label=dev&tags=tag3%3Dvalue3&tags=tag2%3Dvalue2&tags=tag1%3Dvalue1",
+        "?$select=key&after=abcdefg&api-version=2023-11-01&key=*&label=dev&tags=tag3%3Dvalue3&tags=tag2%3Dvalue2&tags=tag1%3Dvalue1",
       ),
     ).toBe(true);
   });
@@ -40,24 +40,4 @@ describe("urlQueryParamsNormalizationPolicy", () => {
     const finalUrl = response.headers.get("url-lookup")!;
     expect(finalUrl.endsWith("?api-version=2023-11-01&tags=tag2&tags=tag1")).toBe(true);
   });
-
-  it("keeps key with no value", async () => {
-    const policy = queryParamPolicy();
-    const request = createPipelineRequest({
-      url: "https://example.azconfig.io/kv?tags&api-version=2023-11-01",
-    });
-    const response = await policy.sendRequest(request, mockNext());
-    const finalUrl = response.headers.get("url-lookup")!;
-    expect(finalUrl.endsWith("?api-version=2023-11-01&tags=")).toBe(true);
-  });
-
-  it("removes redundant &", async () => {
-    const policy = queryParamPolicy();
-    const request = createPipelineRequest({
-      url: "https://example.azconfig.io/kv?&&&",
-    });
-    const response = await policy.sendRequest(request, mockNext());
-    const finalUrl = response.headers.get("url-lookup")!;
-    expect(finalUrl.endsWith("?")).toBe(true);
-  });
 });

From dcf63a68ca1fc10c25b92c831227bbd6b25cc58d Mon Sep 17 00:00:00 2001
From: Zhiyuan Liang <zhiyuanliang@microsoft.com>
Date: Thu, 23 Oct 2025 13:36:29 +0800
Subject: [PATCH 14/21] update test

---
 sdk/appconfiguration/app-configuration/assets.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sdk/appconfiguration/app-configuration/assets.json b/sdk/appconfiguration/app-configuration/assets.json
index 085e3044ecf7..3771e6ef9f2e 100644
--- a/sdk/appconfiguration/app-configuration/assets.json
+++ b/sdk/appconfiguration/app-configuration/assets.json
@@ -2,5 +2,5 @@
   "AssetsRepo": "Azure/azure-sdk-assets",
   "AssetsRepoPrefixPath": "js",
   "TagPrefix": "js/appconfiguration/app-configuration",
-  "Tag": "js/appconfiguration/app-configuration_55c63bcf25"
+  "Tag": "js/appconfiguration/app-configuration_e47e6a8bab"
 }

From ccbb1556864824d1502c85dbeceb1c95990c3669 Mon Sep 17 00:00:00 2001
From: Zhiyuan Liang <zhiyuanliang@microsoft.com>
Date: Thu, 23 Oct 2025 14:33:59 +0800
Subject: [PATCH 15/21] update test

---
 .../test/internal/queryParamPolicy.spec.ts             | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts b/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts
index 4bdb79d2871d..e1428a944d01 100644
--- a/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts
+++ b/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts
@@ -40,4 +40,14 @@ describe("urlQueryParamsNormalizationPolicy", () => {
     const finalUrl = response.headers.get("url-lookup")!;
     expect(finalUrl.endsWith("?api-version=2023-11-01&tags=tag2&tags=tag1")).toBe(true);
   });
+
+  it("keeps empty value", async () => {
+    const policy = queryParamPolicy();
+    const request = createPipelineRequest({
+      url: "https://example.azconfig.io/kv?key=&api-version=2023-11-01",
+    });
+    const response = await policy.sendRequest(request, mockNext());
+    const finalUrl = response.headers.get("url-lookup")!;
+    expect(finalUrl.endsWith("?api-version=2023-11-01&key=")).toBe(true);
+  });
 });

From 5218bafc0046d54f2deb47ce78b0f4304f1d6fdb Mon Sep 17 00:00:00 2001
From: Zhiyuan Liang <zhiyuanliang@microsoft.com>
Date: Thu, 23 Oct 2025 14:40:12 +0800
Subject: [PATCH 16/21] handle corner case that query doesn't have =

---
 .../app-configuration/src/internal/queryParamPolicy.ts        | 2 +-
 .../app-configuration/test/internal/queryParamPolicy.spec.ts  | 4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts b/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts
index c463af05930b..3b184356193b 100644
--- a/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts
+++ b/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts
@@ -29,7 +29,7 @@ export function queryParamPolicy(): PipelinePolicy {
         const params: ParamEntry[] = [];
         for (const entry of url.search.substring(1).split("&")) {
           const [name, value] = entry.split("=", 2);
-          params.push({ lowercaseName: name.toLowerCase(), value });
+          params.push({ lowercaseName: name.toLowerCase(), value: value ?? "" });
         }
 
         // Modern JavaScript Array.prototype.sort is stable
diff --git a/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts b/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts
index e1428a944d01..70d6545b89a9 100644
--- a/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts
+++ b/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts
@@ -44,10 +44,10 @@ describe("urlQueryParamsNormalizationPolicy", () => {
   it("keeps empty value", async () => {
     const policy = queryParamPolicy();
     const request = createPipelineRequest({
-      url: "https://example.azconfig.io/kv?key=&api-version=2023-11-01",
+      url: "https://example.azconfig.io/kv?key=&api-version=2023-11-01&key1",
     });
     const response = await policy.sendRequest(request, mockNext());
     const finalUrl = response.headers.get("url-lookup")!;
-    expect(finalUrl.endsWith("?api-version=2023-11-01&key=")).toBe(true);
+    expect(finalUrl.endsWith("?api-version=2023-11-01&key=&key1=")).toBe(true);
   });
 });

From 4b538f55b1001e3758a8669b325c7506fc5979bc Mon Sep 17 00:00:00 2001
From: Zhiyuan Liang <zhiyuanliang@microsoft.com>
Date: Thu, 23 Oct 2025 15:04:25 +0800
Subject: [PATCH 17/21] handle corner case that query is empty

---
 .../src/internal/queryParamPolicy.ts          |  3 +++
 .../test/internal/queryParamPolicy.spec.ts    | 22 ++++++++++++++++++-
 2 files changed, 24 insertions(+), 1 deletion(-)

diff --git a/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts b/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts
index 3b184356193b..acad358a3c8a 100644
--- a/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts
+++ b/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts
@@ -28,6 +28,9 @@ export function queryParamPolicy(): PipelinePolicy {
 
         const params: ParamEntry[] = [];
         for (const entry of url.search.substring(1).split("&")) {
+          if (entry === "") {
+            continue;
+          }
           const [name, value] = entry.split("=", 2);
           params.push({ lowercaseName: name.toLowerCase(), value: value ?? "" });
         }
diff --git a/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts b/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts
index 70d6545b89a9..e84b11c4e639 100644
--- a/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts
+++ b/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts
@@ -41,7 +41,7 @@ describe("urlQueryParamsNormalizationPolicy", () => {
     expect(finalUrl.endsWith("?api-version=2023-11-01&tags=tag2&tags=tag1")).toBe(true);
   });
 
-  it("keeps empty value", async () => {
+  it("keeps empty parameter value", async () => {
     const policy = queryParamPolicy();
     const request = createPipelineRequest({
       url: "https://example.azconfig.io/kv?key=&api-version=2023-11-01&key1",
@@ -50,4 +50,24 @@ describe("urlQueryParamsNormalizationPolicy", () => {
     const finalUrl = response.headers.get("url-lookup")!;
     expect(finalUrl.endsWith("?api-version=2023-11-01&key=&key1=")).toBe(true);
   });
+
+  it("removes redundant &", async () => {
+    const policy = queryParamPolicy();
+    const request = createPipelineRequest({
+      url: "https://example.azconfig.io/kv?b=2&&a=1",
+    });
+    const response = await policy.sendRequest(request, mockNext());
+    const finalUrl = response.headers.get("url-lookup")!;
+    expect(finalUrl.endsWith("?a=1&b=2")).toBe(true);
+  });
+
+  it("skips when no query parameters are present", async () => {
+    const policy = queryParamPolicy();
+    const request = createPipelineRequest({
+      url: "https://example.azconfig.io/kv?",
+    });
+    const response = await policy.sendRequest(request, mockNext());
+    const finalUrl = response.headers.get("url-lookup")!;
+    expect(finalUrl.endsWith("/kv?")).toBe(true);
+  });
 });

From 43994c3e14a01b980006b64a5d7332af4e06bf02 Mon Sep 17 00:00:00 2001
From: Zhiyuan Liang <zhiyuanliang@microsoft.com>
Date: Thu, 23 Oct 2025 15:43:39 +0800
Subject: [PATCH 18/21] update testcase

---
 .../app-configuration/test/internal/queryParamPolicy.spec.ts  | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts b/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts
index e84b11c4e639..990b74d70751 100644
--- a/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts
+++ b/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts
@@ -44,11 +44,11 @@ describe("urlQueryParamsNormalizationPolicy", () => {
   it("keeps empty parameter value", async () => {
     const policy = queryParamPolicy();
     const request = createPipelineRequest({
-      url: "https://example.azconfig.io/kv?key=&api-version=2023-11-01&key1",
+      url: "https://example.azconfig.io/kv?key=&api-version=2023-11-01&key1&=",
     });
     const response = await policy.sendRequest(request, mockNext());
     const finalUrl = response.headers.get("url-lookup")!;
-    expect(finalUrl.endsWith("?api-version=2023-11-01&key=&key1=")).toBe(true);
+    expect(finalUrl.endsWith("?=&api-version=2023-11-01&key=&key1=")).toBe(true);
   });
 
   it("removes redundant &", async () => {

From 445920a0827a239e3fb1be1c06ff78c830dae49d Mon Sep 17 00:00:00 2001
From: Zhiyuan Liang <zhiyuanliang@microsoft.com>
Date: Thu, 23 Oct 2025 16:26:23 +0800
Subject: [PATCH 19/21] update testcase

---
 sdk/appconfiguration/app-configuration/CHANGELOG.md    |  2 +-
 .../test/internal/queryParamPolicy.spec.ts             | 10 ++++++++++
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/sdk/appconfiguration/app-configuration/CHANGELOG.md b/sdk/appconfiguration/app-configuration/CHANGELOG.md
index 41bdede9d539..2a66e984e626 100644
--- a/sdk/appconfiguration/app-configuration/CHANGELOG.md
+++ b/sdk/appconfiguration/app-configuration/CHANGELOG.md
@@ -25,7 +25,7 @@
 
 ### Other Changes
 
-- Update README with a link to [_`@azure/app-configuration-provider`_](https://www.npmjs.com/package/@azure/app-configuration-provider). [#33152](https://github.com/Azure/azure-sdk-for-js/pull/33152)
+- Update README with a link to [*`@azure/app-configuration-provider`*](https://www.npmjs.com/package/@azure/app-configuration-provider). [#33152](https://github.com/Azure/azure-sdk-for-js/pull/33152)
 
 ## 1.9.0-beta.1 (2025-03-11)
 
diff --git a/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts b/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts
index 990b74d70751..dc8ac3b0ebe3 100644
--- a/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts
+++ b/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts
@@ -31,6 +31,16 @@ describe("urlQueryParamsNormalizationPolicy", () => {
     ).toBe(true);
   });
 
+  it("keeps original encoded parameter value", async () => {
+    const policy = queryParamPolicy();
+    const request = createPipelineRequest({
+      url: "https://example.azconfig.io/kv?key=%25%20%2B",
+    });
+    const response = await policy.sendRequest(request, mockNext());
+    const finalUrl = response.headers.get("url-lookup")!;
+    expect(finalUrl.endsWith("?key=%25%20%2B")).toBe(true);
+  });
+
   it("keeps original order of query parameters", async () => {
     const policy = queryParamPolicy();
     const request = createPipelineRequest({

From 1fdc43a8117dae4977ba91777695dc508e2b1568 Mon Sep 17 00:00:00 2001
From: Zhiyuan Liang <zhiyuanliang@microsoft.com>
Date: Thu, 23 Oct 2025 17:05:00 +0800
Subject: [PATCH 20/21] update testcase

---
 .../app-configuration/test/internal/queryParamPolicy.spec.ts  | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts b/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts
index dc8ac3b0ebe3..5b086359bb1e 100644
--- a/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts
+++ b/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts
@@ -34,11 +34,11 @@ describe("urlQueryParamsNormalizationPolicy", () => {
   it("keeps original encoded parameter value", async () => {
     const policy = queryParamPolicy();
     const request = createPipelineRequest({
-      url: "https://example.azconfig.io/kv?key=%25%20%2B",
+      url: "https://example.azconfig.io/kv?key=%25%20%2B&label=%00",
     });
     const response = await policy.sendRequest(request, mockNext());
     const finalUrl = response.headers.get("url-lookup")!;
-    expect(finalUrl.endsWith("?key=%25%20%2B")).toBe(true);
+    expect(finalUrl.endsWith("?key=%25%20%2B&label=%00")).toBe(true);
   });
 
   it("keeps original order of query parameters", async () => {

From e35413aed829f49078d466591638501d99c1b57b Mon Sep 17 00:00:00 2001
From: Zhiyuan Liang <zhiyuanliang@microsoft.com>
Date: Fri, 24 Oct 2025 15:59:18 +0800
Subject: [PATCH 21/21] update

---
 .../app-configuration/src/internal/queryParamPolicy.ts    | 8 +++++---
 .../test/internal/queryParamPolicy.spec.ts                | 2 +-
 2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts b/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts
index acad358a3c8a..81026a0465c3 100644
--- a/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts
+++ b/sdk/appconfiguration/app-configuration/src/internal/queryParamPolicy.ts
@@ -31,8 +31,10 @@ export function queryParamPolicy(): PipelinePolicy {
           if (entry === "") {
             continue;
           }
-          const [name, value] = entry.split("=", 2);
-          params.push({ lowercaseName: name.toLowerCase(), value: value ?? "" });
+          const equalIndex = entry.indexOf("=");
+          const name = equalIndex === -1 ? entry : entry.substring(0, equalIndex);
+          const value = equalIndex === -1 ? "" : entry.substring(equalIndex + 1);
+          params.push({ lowercaseName: name.toLowerCase(), value });
         }
 
         // Modern JavaScript Array.prototype.sort is stable
@@ -46,7 +48,7 @@ export function queryParamPolicy(): PipelinePolicy {
           return 0;
         });
 
-        const newSearchParams = params
+        const newSearchParams: string = params
           .map(({ lowercaseName, value }) => `${lowercaseName}=${value}`)
           .join("&");
 
diff --git a/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts b/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts
index 5b086359bb1e..f3ae620d8e81 100644
--- a/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts
+++ b/sdk/appconfiguration/app-configuration/test/internal/queryParamPolicy.spec.ts
@@ -71,7 +71,7 @@ describe("urlQueryParamsNormalizationPolicy", () => {
     expect(finalUrl.endsWith("?a=1&b=2")).toBe(true);
   });
 
-  it("skips when no query parameters are present", async () => {
+  it("skips when no query parameter is present", async () => {
     const policy = queryParamPolicy();
     const request = createPipelineRequest({
       url: "https://example.azconfig.io/kv?",