feat: add requestHandler ctor pass through type

Author: kuhe

.changeset/dry-balloons-smell.md

@@ -0,0 +1,5 @@
+---
+"@smithy/protocol-http": minor
+---
+
+add RequestHandlerParams type for ctor passthrough

packages/protocol-http/package.json

@@ -16,6 +16,13 @@
   "main": "./dist-cjs/index.js",
   "module": "./dist-es/index.js",
   "types": "./dist-types/index.d.ts",
+  "browser": {
+    "./dist-es/httpHandlerInitialization": "./dist-es/httpHandlerInitialization.browser"
+  },
+  "react-native": {
+    "./dist-es/httpHandlerInitialization": "./dist-es/httpHandlerInitialization.browser",
+    "./dist-cjs/httpHandlerInitialization": "./dist-cjs/httpHandlerInitialization.browser"
+  },
   "author": {
     "name": "AWS Smithy Team",
     "email": "",

packages/protocol-http/src/httpHandler.ts

@@ -1,5 +1,6 @@
 import { HttpHandlerOptions, RequestHandler } from "@smithy/types";
 
+import { RequestHandlerParams } from "./httpHandlerInitialization";
 import { HttpRequest } from "./httpRequest";
 import { HttpResponse } from "./httpResponse";
 
@@ -23,3 +24,24 @@ export type HttpHandler<HttpHandlerConfig extends object = {}> = RequestHandler<
    */
   httpHandlerConfigs(): HttpHandlerConfig;
 };
+
+/**
+ * @internal
+ *
+ * @param requestHandlerOrOptions - a custom implementation or options for the default factory.
+ * @param factory - creates a new instance if requestHandlerOrOptions is not one.
+ *
+ * @returns a request handler instance provided by the requestHandlerOrOptions, constructor, or factory.
+ */
+export function makeHandler<HandlerType extends HttpHandler<RequestHandlerParams>>(
+  requestHandlerOrOptions: RequestHandlerParams | HandlerType,
+  factory: (options?: RequestHandlerParams) => HandlerType
+) {
+  if (typeof (requestHandlerOrOptions as any)?.handle === "function") {
+    // is already an instance of RequestHandler.
+    return requestHandlerOrOptions as HandlerType;
+  }
+
+  // input is ctor options or undefined, use the factory.
+  return factory(requestHandlerOrOptions as RequestHandlerParams);
+}

packages/protocol-http/src/httpHandlerInitialization.browser.ts

@@ -0,0 +1,15 @@
+/**
+ * Alternate compilation for browser excluding http Agent types.
+ *
+ * @internal
+ */
+export type DefaultRequestHandlerInitializationPassThroughParameters = FetchHttpHandlerOptions;
+
+/**
+ * Copy of the options in @smithy/fetch-http-handler FetchHttpHandler class.
+ * Not imported due to dependency ordering.
+ */
+interface FetchHttpHandlerOptions {
+  requestTimeout?: number;
+  keepAlive?: boolean;
+}

packages/protocol-http/src/httpHandlerInitialization.ts

@@ -0,0 +1,35 @@
+import type { Agent as hAgent } from "http";
+import type { Agent as hsAgent } from "https";
+
+/**
+ *
+ * This type represents an alternate client constructor option for the entry
+ * "requestHandler". Instead of providing an instance of a requestHandler, the user
+ * may provide the requestHandler's constructor options for either the
+ * NodeHttpHandler or FetchHttpHandler.
+ *
+ * For other RequestHandlers, constructor parameter passthrough is not available.
+ *
+ * @public
+ */
+export type RequestHandlerParams = NodeHttpHandlerOptions | FetchHttpHandlerOptions;
+
+/**
+ * Copy of the options in @smithy/node-http-handler NodeHttpHandler class.
+ * Not imported due to dependency ordering.
+ */
+export interface NodeHttpHandlerOptions {
+  connectionTimeout?: number;
+  requestTimeout?: number;
+  httpAgent?: hAgent;
+  httpsAgent?: hsAgent;
+}
+
+/**
+ * Copy of the options in @smithy/fetch-http-handler FetchHttpHandler class.
+ * Not imported due to dependency ordering.
+ */
+export interface FetchHttpHandlerOptions {
+  requestTimeout?: number;
+  keepAlive?: boolean;
+}

packages/protocol-http/src/index.ts

@@ -2,6 +2,7 @@ export * from "./extensions";
 export * from "./Field";
 export * from "./Fields";
 export * from "./httpHandler";
+export * from "./httpHandlerInitialization";
 export * from "./httpRequest";
 export * from "./httpResponse";
 export * from "./isValidHostname";