fix(gax): widen port to number | string in GrpcClientOptions (#9542)

Widens `port` from `number` to `number | string` on `GrpcClientOptions`
and `ClientStubOptions` in `google-gax` to restore type compatibility
with downstream client libraries (such as `@google-cloud/pubsub`, whose
`ClientConfig` extends `gax.GrpcClientOptions` with `port?: string |
number`)

#9496 added `port?: number` to `GrpcClientOptions` (released in
`google-gax@6.11.0`). Because `@google-cloud/pubsub`'s `ClientConfig`
interface extends `gax.GrpcClientOptions` and declares `port?: string |
number`, TypeScript compilation with `skipLibCheck: false` (such as in
`@google-cloud/pubsub`'s `system-test/install.ts`) fails

Author: shivanee-p

core/packages/gax/src/fallback.ts

@@ -161,7 +161,8 @@ export class GrpcClient {
     this._servicePath =
       (options as GrpcClientOptions).servicePath ||
       (options as GrpcClientOptions).apiEndpoint;
-    this._port = (options as GrpcClientOptions).port;
+    const rawPort = (options as GrpcClientOptions).port;
+    this._port = typeof rawPort === 'string' ? parseInt(rawPort, 10) : rawPort;
   }
 
   /**
@@ -371,7 +372,8 @@ export class GrpcClient {
       servicePort = parseInt(match[2]);
     }
     if (opts.port) {
-      servicePort = opts.port;
+      servicePort =
+        typeof opts.port === 'string' ? parseInt(opts.port, 10) : opts.port;
     } else if (!servicePort) {
       servicePort = 443;
     }

core/packages/gax/src/grpc.ts

@@ -55,7 +55,7 @@ export interface GrpcClientOptions extends GoogleAuthOptions {
   universeDomain?: string;
   servicePath?: string;
   apiEndpoint?: string;
-  port?: number;
+  port?: number | string;
 }
 
 export interface MetadataValue {
@@ -104,7 +104,7 @@ export type GrpcModule = typeof grpc;
 export interface ClientStubOptions {
   protocol?: string;
   servicePath?: string;
-  port?: number;
+  port?: number | string;
   sslCreds?: grpc.ChannelCredentials;
   [index: string]: string | number | undefined | {};
   // For mtls:
@@ -180,7 +180,10 @@ export class GrpcClient {
     this.auth = options.auth || new GoogleAuth(options);
     this.fallback = false;
     this._servicePath = options.servicePath || options.apiEndpoint;
-    this._port = options.port;
+    this._port =
+      typeof options.port === 'string'
+        ? parseInt(options.port, 10)
+        : options.port;
 
     const minimumVersion = 10;
     const major = Number(process.version.match(/^v(\d+)/)?.[1]);

core/packages/gax/src/observability/metadataResolver.ts

@@ -135,8 +135,8 @@ export function extractFromSettings(
     | {
         servicePath?: string;
         apiEndpoint?: string;
-        port?: number;
-        servicePort?: number;
+        port?: number | string;
+        servicePort?: number | string;
       }
     | undefined;
   const endpoint =
@@ -155,11 +155,14 @@ export function extractFromSettings(
   }
 
   // Resolve server port if not already parsed from endpoint.
-  const port =
-    (settings as {port?: number; servicePort?: number}).port ||
-    (settings as {port?: number; servicePort?: number}).servicePort ||
+  const rawPort =
+    (settings as {port?: number | string; servicePort?: number | string})
+      .port ||
+    (settings as {port?: number | string; servicePort?: number | string})
+      .servicePort ||
     otherArgs?.port ||
     otherArgs?.servicePort;
+  const port = typeof rawPort === 'string' ? parseInt(rawPort, 10) : rawPort;
   if (port && typeof port === 'number' && !result.serverPort) {
     result.serverPort = port;
   }

core/packages/gax/src/resumableUpload.ts

@@ -200,7 +200,7 @@ export interface ResumableUploadContext {
   /** The hostname of the API service endpoint. */
   servicePath: string;
   /** The port of the API service endpoint. */
-  servicePort: number;
+  servicePort: number | string;
   /** The protocol (usually `https`). */
   protocol: string;
   /** The protobuf method descriptor for the resumable upload RPC. */