Stop depending on @types/tunnel for createTunnel

Porting fix from v1.x branch https://github.com/Azure/ms-rest-js/pull/434

Changelog.md

@@ -1,5 +1,8 @@
 # Changelog
 
+## 2.2.3 - 2021-02-10
+- Dependent projects of @azure/ms-rest-js no longer need to have a dev dependency on @types/tunnel.
+
 ## 2.2.2 - 2021-02-09
 - Port fix for nextLink issue from core-http (PR [#426](https://github.com/Azure/ms-rest-js/pull/426))
 - Fix abort signal event handler memory leak (PR [#425](https://github.com/Azure/ms-rest-js/pull/425))

lib/proxyAgent.ts

@@ -40,10 +40,32 @@ export function createProxyAgent(
   return proxyAgent;
 }
 
+// Duplicate tunnel.HttpsOverHttpsOptions to avoid exporting createTunnel() with dependency on @types/tunnel
+// createIunnel() is only imported by tests.
+export interface HttpsProxyOptions {
+  host: string;
+  port: number;
+  localAddress?: string;
+  proxyAuth?: string;
+  headers?: { [key: string]: any };
+  ca?: Buffer[];
+  servername?: string;
+  key?: Buffer;
+  cert?: Buffer;
+}
+
+interface HttpsOverHttpsOptions {
+  maxSockets?: number;
+  ca?: Buffer[];
+  key?: Buffer;
+  cert?: Buffer;
+  proxy?: HttpsProxyOptions;
+}
+
 export function createTunnel(
   isRequestHttps: boolean,
   isProxyHttps: boolean,
-  tunnelOptions: tunnel.HttpsOverHttpsOptions
+  tunnelOptions: HttpsOverHttpsOptions
 ): http.Agent | https.Agent {
   if (isRequestHttps && isProxyHttps) {
     return tunnel.httpsOverHttps(tunnelOptions);

lib/util/constants.ts

@@ -7,7 +7,7 @@ export const Constants = {
    * @const
    * @type {string}
    */
-  msRestVersion: "2.2.2",
+  msRestVersion: "2.2.3",
 
   /**
    * Specifies HTTP.

package.json

@@ -5,7 +5,7 @@
     "email": "azsdkteam@microsoft.com",
     "url": "https://github.com/Azure/ms-rest-js"
   },
-  "version": "2.2.2",
+  "version": "2.2.3",
   "description": "Isomorphic client Runtime for Typescript/node.js/browser javascript client libraries generated using AutoRest",
   "tags": [
     "isomorphic",