Redesign of http server module

async/deferred.ts

@@ -0,0 +1,27 @@
+// Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
+
+export type Deferred<T = any, R = Error> = {
+  promise: Promise<T>;
+  resolve: (t?: T) => void;
+  reject: (r?: R) => void;
+};
+
+/** Create deferred promise that can be resolved and rejected by outside */
+export function defer<T>(): Deferred<T> {
+  let resolve = () => {};
+  let reject = () => {};
+  const promise = new Promise<T>((res, rej) => {
+    resolve = res;
+    reject = rej;
+  });
+  return { promise, resolve, reject };
+}
+
+export function isDeferred(x): x is Deferred {
+  return (
+    typeof x === "object" &&
+    x.promise instanceof Promise &&
+    typeof x["resolve"] === "function" &&
+    typeof x["reject"] === "function"
+  );
+}

async/deferred_test.ts

@@ -0,0 +1,16 @@
+// Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
+
+import { assert, test } from "../testing/mod.ts";
+import { defer, isDeferred } from "./deferred.ts";
+
+test(async function asyncIsDeferred() {
+  const d = defer();
+  assert.assert(isDeferred(d));
+  assert.assert(
+    isDeferred({
+      promise: null,
+      resolve: () => {},
+      reject: () => {}
+    }) === false
+  );
+});

http/file_server.ts

@@ -10,7 +10,7 @@ import {
   listenAndServe,
   ServerRequest,
   setContentLength,
-  Response
+  ServerResponse
 } from "./server.ts";
 import { cwd, DenoError, ErrorKind, args, stat, readDir, open } from "deno";
 import { extname } from "../fs/path.ts";
@@ -195,14 +195,14 @@ async function serveFallback(req: ServerRequest, e: Error) {
   }
 }
 
-function serverLog(req: ServerRequest, res: Response) {
+function serverLog(req: ServerRequest, res: ServerResponse) {
   const d = new Date().toISOString();
   const dateFmt = `[${d.slice(0, 10)} ${d.slice(11, 19)}]`;
   const s = `${dateFmt} "${req.method} ${req.url} ${req.proto}" ${res.status}`;
   console.log(s);
 }
 
-function setCORS(res: Response) {
+function setCORS(res: ServerResponse) {
   if (!res.headers) {
     res.headers = new Headers();
   }
@@ -217,7 +217,7 @@ listenAndServe(addr, async req => {
   const fileName = req.url.replace(/\/$/, "");
   const filePath = currentDir + fileName;
 
-  let response: Response;
+  let response: ServerResponse;
 
   try {
     const fileInfo = await stat(filePath);