[Perf] Call runAsync() once before starting recording

sdk/test-utils/perfstress/CHANGELOG.md

@@ -2,6 +2,11 @@
 
 ## 1.0.0 (Unreleased)
 
+### 2021-10-01
+
+- Calls runAsync() once before starting recording, to avoid capturing one-time setup like authorization requests.
+  [#17993](https://github.com/Azure/azure-sdk-for-js/pull/17993)
+
 ### 2021-09-29
 
 - Allows connecting to the proxy-tool with https with the "insecure" boolean option.

sdk/test-utils/perfstress/package.json

@@ -68,6 +68,7 @@
     "@types/minimist": "~1.2.0"
   },
   "devDependencies": {
+    "@azure/core-client": "^1.3.1",
     "@azure/eslint-plugin-azure-sdk": "^3.0.0",
     "@types/node": "^12.0.0",
     "@types/node-fetch": "^2.5.0",

sdk/test-utils/perfstress/src/program.ts

@@ -366,6 +366,9 @@ export class PerfStressProgram {
       );
     }
 
+    // Call Run() once before starting recording, to avoid capturing one-time setup like authorization requests.
+    await test.runAsync!();
+
     await recorder.startRecording();
     recorder._mode = "record";
     await test.runAsync!();

sdk/test-utils/perfstress/test/index.spec.ts

@@ -12,6 +12,7 @@ import { Exception } from "./exception.spec";
 import { PerfStressPolicyTest } from "./perfStressPolicy.spec";
 import { SleepTest } from "./sleep.spec";
 import { NodeFetchTest } from "./nodeFetch.spec";
+import { ServiceClientGetTest } from "./serviceClientGet.spec";
 
 console.log("=== Starting the perfStress test ===");
 
@@ -24,7 +25,8 @@ const perfStressProgram = new PerfStressProgram(
     Exception,
     PerfStressPolicyTest,
     SleepTest,
-    NodeFetchTest
+    NodeFetchTest,
+    ServiceClientGetTest
   ])
 );
 

sdk/test-utils/perfstress/test/nodeFetch.spec.ts

@@ -23,8 +23,8 @@ export class NodeFetchTest extends PerfStressTest<NodeFetchOptions> {
       description: "Required option",
       shortName: "u",
       longName: "url",
-      defaultValue: "http://bing.com",
-      value: "http://bing.com"
+      defaultValue: "http://www.example.org",
+      value: "http://www.example.org"
     }
   };
 

sdk/test-utils/perfstress/test/serviceClientGet.spec.ts

@@ -0,0 +1,67 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
+import { createPipelineRequest, PipelineRequest } from "@azure/core-rest-pipeline";
+import { ServiceClient } from "@azure/core-client";
+import { PerfStressTest, PerfStressOptionDictionary, drainStream } from "../src";
+import { getCachedHttpsAgent } from "../src/utils";
+
+interface ServiceClientGetOptions {
+  "first-run-extra-requests": number;
+  url: string;
+}
+
+export class ServiceClientGetTest extends PerfStressTest<ServiceClientGetOptions> {
+  client: ServiceClient;
+  request: PipelineRequest;
+  firstRun: boolean = true;
+
+  public options: PerfStressOptionDictionary<ServiceClientGetOptions> = {
+    "first-run-extra-requests": {
+      description:
+        "Extra requests to send on first run.  " +
+        "Simulates SDKs which require extra requests (like authentication) on first API call.",
+      defaultValue: 0
+    },
+    url: {
+      required: true,
+      description: "URL to retrieve",
+      shortName: "u",
+      longName: "url"
+    }
+  };
+
+  constructor() {
+    super();
+
+    const url = this.parsedOptions.url.value as string;
+    const insecure = this.parsedOptions.insecure.value as boolean;
+
+    this.client = this.configureClient(new ServiceClient());
+    this.request = createPipelineRequest({
+      allowInsecureConnection: true,
+      streamResponseStatusCodes: new Set([200]),
+      url: url
+    });
+
+    if (insecure && url.toLowerCase().startsWith("https:")) {
+      this.request.agent = getCachedHttpsAgent(true);
+    }
+  }
+
+  async runAsync(): Promise<void> {
+    var response;
+
+    if (this.firstRun) {
+      const extraRequests = this.parsedOptions["first-run-extra-requests"].value as number;
+      for (var i = 0; i < extraRequests; i++) {
+        response = await this.client.sendRequest(this.request);
+        await drainStream(response.readableStreamBody!);
+      }
+      this.firstRun = false;
+    }
+
+    response = await this.client.sendRequest(this.request);
+    await drainStream(response.readableStreamBody!);
+  }
+}