feat: add a middleware inserting right host header (#567)

Author: AllanZhengYP

packages/node-http-handler/src/node-http-handler.spec.ts

@@ -41,6 +41,10 @@ describe("NodeHttpHandler", () => {
     afterAll(() => {
       mockHttpServer.close();
     });
+    it("has metadata", () => {
+      const nodeHttpHandler = new NodeHttpHandler();
+      expect(nodeHttpHandler.metadata.handlerProtocol).toContain("http/1.1");
+    });
     it("can send http requests", async () => {
       const mockResponse = {
         statusCode: 200,

packages/node-http-handler/src/node-http-handler.ts

@@ -33,6 +33,8 @@ export class NodeHttpHandler implements HttpHandler {
   private readonly httpsAgent: https.Agent;
   private readonly connectionTimeout?: number;
   private readonly socketTimeout?: number;
+  // Node http handler is hard-coded to http/1.1: https://github.com/nodejs/node/blob/ff5664b83b89c55e4ab5d5f60068fb457f1f5872/lib/_http_server.js#L286
+  public readonly metadata = { handlerProtocol: "http/1.1" };
 
   constructor({
     connectionTimeout,

packages/node-http-handler/src/node-http2-handler.spec.ts

@@ -44,6 +44,10 @@ describe("NodeHttp2Handler", () => {
     mockH2Server.close();
   });
 
+  it("has metadata", () => {
+    expect(nodeH2Handler.metadata.handlerProtocol).toContain("h2");
+  });
+
   describe("connectionPool", () => {
     it("is empty on initialization", () => {
       // @ts-ignore: access private property

packages/node-http-handler/src/node-http2-handler.ts

@@ -27,6 +27,7 @@ export interface NodeHttp2Options {
 
 export class NodeHttp2Handler implements HttpHandler {
   private readonly connectionPool: Map<string, ClientHttp2Session>;
+  public readonly metadata = { handlerProtocol: "h2" };
 
   constructor(private readonly http2Options: NodeHttp2Options = {}) {
     this.connectionPool = new Map<string, ClientHttp2Session>();

packages/smithy-client/src/client.ts

@@ -70,7 +70,7 @@ export class Client<
     optionsOrCb?: HandlerOptions | ((err: any, data?: OutputType) => void),
     cb?: (err: any, data?: OutputType) => void
   ): Promise<OutputType> | void {
-    const options = typeof optionsOrCb !== "function" ? optionsOrCb : {};
+    const options = typeof optionsOrCb !== "function" ? optionsOrCb : undefined;
     const callback =
       typeof optionsOrCb === "function"
         ? (optionsOrCb as ((err: any, data?: OutputType) => void))