feat(unstable): change Deno.serve() API (#15498)

- Merge "Deno.serve()" and "Deno.serveTls()" API
- Remove first argument and use "fetch" field options instead
- Update type declarations
- Add more documentation

12 files changed, 347 insertions, 324 deletions

diff --git a/cli/bench/http/deno_flash_hono_router.js b/cli/bench/http/deno_flash_hono_router.js
index af6adc9ba..4c3336c63 100644
--- a/cli/bench/http/deno_flash_hono_router.js
+++ b/cli/bench/http/deno_flash_hono_router.js
@@ -7,4 +7,4 @@ const [hostname, port] = addr.split(":");
 const app = new Hono();
 app.get("/", (c) => c.text("Hello, World!"));
 
-Deno.serve(app.fetch, { port: Number(port), hostname });
+Deno.serve({ fetch: app.fetch, port: Number(port), hostname });
diff --git a/cli/bench/http/deno_flash_send_file.js b/cli/bench/http/deno_flash_send_file.js
index db2ad7a82..81e8c4991 100644
--- a/cli/bench/http/deno_flash_send_file.js
+++ b/cli/bench/http/deno_flash_send_file.js
@@ -6,9 +6,9 @@ const { serve } = Deno;
 
 const path = new URL("../testdata/128k.bin", import.meta.url).pathname;
 
-function handler() {
+function fetch() {
   const file = Deno.openSync(path);
   return new Response(file.readable);
 }
 
-serve(handler, { hostname, port: Number(port) });
+serve({ fetch, hostname, port: Number(port) });
diff --git a/cli/bench/http/deno_http_flash.js b/cli/bench/http/deno_http_flash.js
index 5d3de68f4..3823bb9cd 100644
--- a/cli/bench/http/deno_http_flash.js
+++ b/cli/bench/http/deno_http_flash.js
@@ -4,11 +4,12 @@ const addr = Deno.args[0] || "127.0.0.1:4500";
 const [hostname, port] = addr.split(":");
 const { serve } = Deno;
 
-function handler() {
+function fetch() {
   return new Response("Hello World");
 }
 
-serve(handler, {
+serve({
+  fetch,
   hostname,
   port,
 });
diff --git a/cli/bench/http/deno_reactdom_ssr_flash.jsx b/cli/bench/http/deno_reactdom_ssr_flash.jsx
index 571545b27..0d749c634 100644
--- a/cli/bench/http/deno_reactdom_ssr_flash.jsx
+++ b/cli/bench/http/deno_reactdom_ssr_flash.jsx
@@ -19,8 +19,11 @@ const headers = {
 };
 
 serve(
-  async () => {
-    return new Response(await renderToReadableStream(<App />), headers);
+  {
+    fetch: async () => {
+      return new Response(await renderToReadableStream(<App />), headers);
+    },
+    hostname,
+    port,
   },
-  { hostname, port },
 );
diff --git a/cli/bench/testdata/deno_upgrade_http.js b/cli/bench/testdata/deno_upgrade_http.js
index 638761cf6..e3252ffd1 100644
--- a/cli/bench/testdata/deno_upgrade_http.js
+++ b/cli/bench/testdata/deno_upgrade_http.js
@@ -1,13 +1,14 @@
 const { serve, upgradeHttp } = Deno;
 const u8 = Deno.core.encode("HTTP/1.1 101 Switching Protocols\r\n\r\n");
 
-async function handler(req) {
+async function fetch(req) {
   const [conn, _firstPacket] = upgradeHttp(req);
   await conn.write(u8);
   await conn.close();
 }
 
-serve(handler, {
+serve({
+  fetch,
   hostname: "127.0.0.1",
   port: 9000,
 });
diff --git a/cli/diagnostics.rs b/cli/diagnostics.rs
index 7af64d843..6100bc9d5 100644
--- a/cli/diagnostics.rs
+++ b/cli/diagnostics.rs
@@ -64,7 +64,6 @@ const UNSTABLE_DENO_PROPS: &[&str] = &[
   "ChildStatus",
   "SpawnOutput",
   "serve",
-  "serveTls",
   "ServeInit",
   "ServeTlsInit",
   "Handler",
diff --git a/cli/dts/lib.deno.unstable.d.ts b/cli/dts/lib.deno.unstable.d.ts
index 8de2ecf70..9cd6aec03 100644
--- a/cli/dts/lib.deno.unstable.d.ts
+++ b/cli/dts/lib.deno.unstable.d.ts
@@ -1212,28 +1212,26 @@ declare namespace Deno {
   export function unrefTimer(id: number): void;
 
   /**
-   * A handler for HTTP requests. Consumes a request and returns a response.
-   *
-   * Handler allows `void` or `Promise<void>` return type to enable
-   * request upgrades using `Deno.upgradeHttp()` API. It is callers responsibility
-   * to write response manually to the returned connection. Failing to do so
-   * (or not returning a response without an upgrade) will cause the connection
-   * to hang.
-   *
-   * If a handler throws, the server calling the handler will assume the impact
-   * of the error is isolated to the individual request. It will catch the error
-   * and close the underlying connection.
-   *
-   * @category HTTP Server
-   */
-  export type ServeHandler = (
-    request: Request,
-  ) => Response | Promise<Response> | void | Promise<void>;
-
-  /**
    * @category HTTP Server
    */
   export interface ServeInit extends Partial<Deno.ListenOptions> {
+    /**
+     * A handler for HTTP requests. Consumes a request and returns a response.
+     *
+     * Handler allows `void` or `Promise<void>` return type to enable
+     * request upgrades using `Deno.upgradeHttp()` API. It is callers responsibility
+     * to write response manually to the returned connection. Failing to do so
+     * (or not returning a response without an upgrade) will cause the connection
+     * to hang.
+     *
+     * If a handler throws, the server calling the handler will assume the impact
+     * of the error is isolated to the individual request. It will catch the error
+     * and close the underlying connection.
+     */
+    fetch: (
+      request: Request,
+    ) => Response | Promise<Response> | void | Promise<void>;
+
     /** An AbortSignal to close the server and all connections. */
     signal?: AbortSignal;
 
@@ -1263,14 +1261,36 @@ declare namespace Deno {
    * The below example serves with the port 9000.
    *
    * ```ts
-   * Deno.serve((_req) => new Response("Hello, world"));
+   * Deno.serve({
+   *   fetch: (_req) => new Response("Hello, world")
+   * });
    * ```
    *
    * You can change the listening address by the `hostname` and `port` options.
    * The below example serves with the port 3000.
    *
    * ```ts
-   * Deno.serve((_req) => new Response("Hello, world"), { port: 3000 });
+   * Deno.serve({
+   *   fetch: (_req) => new Response("Hello, world"),
+   *   port: 3000
+   * });
+   * ```
+   *
+   * You can close the server by passing a `signal` option. To wait for the server
+   * to close, await the promise returned from the `Deno.serve` API.
+   *
+   * ```ts
+   * const ac = new AbortController();
+   *
+   * Deno.serve({
+   *   fetch: (_req) => new Response("Hello, world"),
+   *   signal: ac.signal
+   * }).then(() => {
+   *   console.log("Server closed");
+   * });
+   *
+   * console.log("Closing server...");
+   * ac.abort();
    * ```
    *
    * `Deno.serve` function prints the message `Listening on http://<hostname>:<port>/`
@@ -1278,7 +1298,8 @@ declare namespace Deno {
    * `onListen` option to override it.
    *
    * ```ts
-   * Deno.serve((_req) => new Response("Hello, world"), {
+   * Deno.serve({
+   *   fetch: (_req) => new Response("Hello, world"),
    *   onListen({ port, hostname }) {
    *     console.log(`Server started at http://${hostname}:${port}`);
    *     // ... more info specific to your server ..
@@ -1286,57 +1307,23 @@ declare namespace Deno {
    * });
    * ```
    *
-   * @param handler The handler for individual HTTP requests.
-   * @param options The options. See `ServeInit` documentation for details.
-   *
-   * @category HTTP Server
-   */
-  export function serve(
-    handler: ServeHandler,
-    options?: ServeInit,
-  ): Promise<void>;
-
-  /** Serves HTTPS requests with the given handler.
-   *
-   * You must specify `key` and `cert` options.
-   *
-   * You can specify an object with a port and hostname option, which is the
-   * address to listen on. The default is port 9000 on hostname "127.0.0.1".
-   *
-   * The below example serves with the default port 8443.
+   * To enable TLS you must specify `key` and `cert` options.
    *
    * ```ts
    * const cert = "-----BEGIN CERTIFICATE-----\n...\n-----END CERTIFICATE-----\n";
    * const key = "-----BEGIN PRIVATE KEY-----\n...\n-----END PRIVATE KEY-----\n";
-   * Deno.serveTls((_req) => new Response("Hello, world"), { cert, key });
-   *
-   * ```
-   *
-   * `Deno.serveTls` function prints the message `Listening on https://<hostname>:<port>/`
-   * on start-up by default. If you like to change this message, you can specify
-   * `onListen` option to override it.
-   *
-   * ```ts
-   * const cert = "-----BEGIN CERTIFICATE-----\n...\n-----END CERTIFICATE-----\n";
-   * const key = "-----BEGIN PRIVATE KEY-----\n...\n-----END PRIVATE KEY-----\n";
-   * Deno.serveTls((_req) => new Response("Hello, world"), {
+   * Deno.serve({
+   *   fetch: (_req) => new Response("Hello, world"),
    *   cert,
-   *   key,
-   *   onListen({ port, hostname }) {
-   *     console.log(`Server started at https://${hostname}:${port}`);
-   *     // ... more info specific to your server ..
-   *   },
+   *   key
    * });
-   * ```
    *
-   * @param handler The handler for individual HTTPS requests.
-   * @param options The options. See `ServeTlsInit` documentation for details.
+   * @param options The options. See `ServeInit` and `ServeTlsInit` documentation for details.
    *
    * @category HTTP Server
    */
-  export function serveTls(
-    handler: ServeHandler,
-    options?: ServeTlsInit,
+  export function serve(
+    options?: ServeInit | ServeTlsInit,
   ): Promise<void>;
 
   /** **UNSTABLE**: new API, yet to be vetter.
diff --git a/cli/tests/unit/flash_test.ts b/cli/tests/unit/flash_test.ts
index 51534c79b..1b979812f 100644
--- a/cli/tests/unit/flash_test.ts
+++ b/cli/tests/unit/flash_test.ts
@@ -41,15 +41,16 @@ Deno.test({ permissions: { net: true } }, async function httpServerBasic() {
   const promise = deferred();
   const listeningPromise = deferred();
 
-  const server = Deno.serve(async (request) => {
-    // FIXME(bartlomieju):
-    // make sure that request can be inspected
-    console.log(request);
-    assertEquals(new URL(request.url).href, "http://127.0.0.1:4501/");
-    assertEquals(await request.text(), "");
-    promise.resolve();
-    return new Response("Hello World", { headers: { "foo": "bar" } });
-  }, {
+  const server = Deno.serve({
+    fetch: async (request) => {
+      // FIXME(bartlomieju):
+      // make sure that request can be inspected
+      console.log(request);
+      assertEquals(new URL(request.url).href, "http://127.0.0.1:4501/");
+      assertEquals(await request.text(), "");
+      promise.resolve();
+      return new Response("Hello World", { headers: { "foo": "bar" } });
+    },
     port: 4501,
     signal: ac.signal,
     onListen: onListen(listeningPromise),
@@ -80,12 +81,13 @@ Deno.test(
     const ac = new AbortController();
 
     let headers: Headers;
-    const server = Deno.serve(async (request) => {
-      await request.text();
-      headers = request.headers;
-      promise.resolve();
-      return new Response("");
-    }, {
+    const server = Deno.serve({
+      fetch: async (request) => {
+        await request.text();
+        headers = request.headers;
+        promise.resolve();
+        return new Response("");
+      },
       port: 2333,
       signal: ac.signal,
       onListen: onListen(listeningPromise),
@@ -116,12 +118,13 @@ Deno.test(
     const listeningPromise = deferred();
 
     let req: Request;
-    const server = Deno.serve(async (request) => {
-      await request.text();
-      req = request;
-      promise.resolve();
-      return new Response("Hello World");
-    }, {
+    const server = Deno.serve({
+      fetch: async (request) => {
+        await request.text();
+        req = request;
+        promise.resolve();
+        return new Response("Hello World");
+      },
       port: 2334,
       signal: ac.signal,
       onListen: onListen(listeningPromise),
@@ -159,11 +162,12 @@ Deno.test(
     const ac = new AbortController();
     const listeningPromise = deferred();
 
-    const server = Deno.serve((request) => {
-      assertEquals(request.body, null);
-      promise.resolve();
-      return new Response("", { headers: {} });
-    }, {
+    const server = Deno.serve({
+      fetch: (request) => {
+        assertEquals(request.body, null);
+        promise.resolve();
+        return new Response("", { headers: {} });
+      },
       port: 4501,
       signal: ac.signal,
       onListen: onListen(listeningPromise),
@@ -202,11 +206,11 @@ Deno.test(
 
     const listeningPromise = deferred();
     const ac = new AbortController();
-
-    const server = Deno.serve((request) => {
-      assert(!request.body);
-      return new Response(stream.readable);
-    }, {
+    const server = Deno.serve({
+      fetch: (request) => {
+        assert(!request.body);
+        return new Response(stream.readable);
+      },
       port: 4501,
       signal: ac.signal,
       onListen: onListen(listeningPromise),
@@ -232,11 +236,12 @@ Deno.test(
     writer.close();
     const listeningPromise = deferred();
     const ac = new AbortController();
-    const server = Deno.serve(async (request) => {
-      const reqBody = await request.text();
-      assertEquals("hello world", reqBody);
-      return new Response("yo");
-    }, {
+    const server = Deno.serve({
+      fetch: async (request) => {
+        const reqBody = await request.text();
+        assertEquals("hello world", reqBody);
+        return new Response("yo");
+      },
       port: 4501,
       signal: ac.signal,
       onListen: onListen(listeningPromise),
@@ -259,7 +264,8 @@ Deno.test(
 Deno.test({ permissions: { net: true } }, async function httpServerClose() {
   const ac = new AbortController();
   const listeningPromise = deferred();
-  const server = Deno.serve(() => new Response("ok"), {
+  const server = Deno.serve({
+    fetch: () => new Response("ok"),
     port: 4501,
     signal: ac.signal,
     onListen: onListen(listeningPromise),
@@ -278,7 +284,8 @@ Deno.test(
   async function httpServerEmptyBlobResponse() {
     const ac = new AbortController();
     const listeningPromise = deferred();
-    const server = Deno.serve(() => new Response(new Blob([])), {
+    const server = Deno.serve({
+      fetch: () => new Response(new Blob([])),
       port: 4501,
       signal: ac.signal,
       onListen: onListen(listeningPromise),
@@ -298,18 +305,19 @@ Deno.test(
 Deno.test({ permissions: { net: true } }, async function httpServerWebSocket() {
   const ac = new AbortController();
   const listeningPromise = deferred();
-  const server = Deno.serve(async (request) => {
-    const {
-      response,
-      socket,
-    } = Deno.upgradeWebSocket(request);
-    socket.onerror = () => fail();
-    socket.onmessage = (m) => {
-      socket.send(m.data);
-      socket.close(1001);
-    };
-    return response;
-  }, {
+  const server = Deno.serve({
+    fetch: async (request) => {
+      const {
+        response,
+        socket,
+      } = Deno.upgradeWebSocket(request);
+      socket.onerror = () => fail();
+      socket.onmessage = (m) => {
+        socket.send(m.data);
+        socket.close(1001);
+      };
+      return response;
+    },
     port: 4501,
     signal: ac.signal,
     onListen: onListen(listeningPromise),
@@ -337,11 +345,12 @@ Deno.test(
     const ac = new AbortController();
 
     let headers: Headers;
-    const server = Deno.serve(async (request) => {
-      headers = request.headers;
-      promise.resolve();
-      return new Response("");
-    }, {
+    const server = Deno.serve({
+      fetch: async (request) => {
+        headers = request.headers;
+        promise.resolve();
+        return new Response("");
+      },
       port: 2333,
       signal: ac.signal,
       onListen: onListen(listeningPromise),
@@ -375,12 +384,13 @@ Deno.test(
 
     let headers: Headers;
     let text: string;
-    const server = Deno.serve(async (request) => {
-      headers = request.headers;
-      text = await request.text();
-      promise.resolve();
-      return new Response("");
-    }, {
+    const server = Deno.serve({
+      fetch: async (request) => {
+        headers = request.headers;
+        text = await request.text();
+        promise.resolve();
+        return new Response("");
+      },
       port: 2333,
       signal: ac.signal,
       onListen: onListen(listeningPromise),
@@ -419,10 +429,11 @@ Deno.test(
     const ac = new AbortController();
     const listeningPromise = deferred();
 
-    const server = Deno.serve(() => {
-      promise.resolve();
-      return new Response("");
-    }, {
+    const server = Deno.serve({
+      fetch: () => {
+        promise.resolve();
+        return new Response("");
+      },
       port: 2333,
       signal: ac.signal,
       onListen: onListen(listeningPromise),
@@ -568,10 +579,11 @@ Deno.test(
       }).pipeThrough(new TextEncoderStream());
     }
 
-    const finished = Deno.serve(() => {
-      promise.resolve();
-      return new Response(periodicStream());
-    }, {
+    const finished = Deno.serve({
+      fetch: () => {
+        promise.resolve();
+        return new Response(periodicStream());
+      },
       port: 4501,
       signal: ac.signal,
       onListen: onListen(listeningPromise),
@@ -598,11 +610,12 @@ Deno.test(
     const listeningPromise = deferred();
     const promise = deferred();
     const ac = new AbortController();
-    const server = Deno.serve((request) => {
-      assertEquals(request.headers.get("X-Header-Test"), "á");
-      promise.resolve();
-      return new Response("hello", { headers: { "X-Header-Test": "Æ" } });
-    }, {
+    const server = Deno.serve({
+      fetch: (request) => {
+        assertEquals(request.headers.get("X-Header-Test"), "á");
+        promise.resolve();
+        return new Response("hello", { headers: { "X-Header-Test": "Æ" } });
+      },
       port: 4501,
       signal: ac.signal,
       onListen: onListen(listeningPromise),
@@ -643,13 +656,14 @@ Deno.test(
     const listeningPromise = deferred();
     const ac = new AbortController();
 
-    const server = Deno.serve(async (request) => {
-      // FIXME:
-      // assertEquals(new URL(request.url).href, "http://127.0.0.1:4501/");
-      assertEquals(await request.text(), "");
-      promise.resolve();
-      return new Response("11");
-    }, {
+    const server = Deno.serve({
+      fetch: async (request) => {
+        // FIXME:
+        // assertEquals(new URL(request.url).href, "http://127.0.0.1:4501/");
+        assertEquals(await request.text(), "");
+        promise.resolve();
+        return new Response("11");
+      },
       port: 4501,
       signal: ac.signal,
       onListen: onListen(listeningPromise),
@@ -696,12 +710,13 @@ Deno.test(
     const listeningPromise = deferred();
     const ac = new AbortController();
 
-    const server = Deno.serve(async (request) => {
-      assertEquals(await request.text(), "");
-      assertEquals(request.headers.get("cookie"), "foo=bar, bar=foo");
-      promise.resolve();
-      return new Response("ok");
-    }, {
+    const server = Deno.serve({
+      fetch: async (request) => {
+        assertEquals(await request.text(), "");
+        assertEquals(request.headers.get("cookie"), "foo=bar, bar=foo");
+        promise.resolve();
+        return new Response("ok");
+      },
       port: 4501,
       signal: ac.signal,
       onListen: onListen(listeningPromise),
@@ -738,11 +753,12 @@ Deno.test(
     await file.write(new Uint8Array(70 * 1024).fill(1)); // 70kb sent in 64kb + 6kb chunks
     file.close();
 
-    const server = Deno.serve(async (request) => {
-      const f = await Deno.open(tmpFile, { read: true });
-      promise.resolve();
-      return new Response(f.readable);
-    }, {
+    const server = Deno.serve({
+      fetch: async (request) => {
+        const f = await Deno.open(tmpFile, { read: true });
+        promise.resolve();
+        return new Response(f.readable);
+      },
       port: 4503,
       signal: ac.signal,
       onListen: onListen(listeningPromise),
@@ -773,10 +789,11 @@ Deno.test(
     const hostname = "localhost";
     const port = 4501;
 
-    const server = Deno.serve(() => {
-      promise.resolve();
-      return new Response("ok");
-    }, {
+    const server = Deno.serve({
+      fetch: () => {
+        promise.resolve();
+        return new Response("ok");
+      },
       port: port,
       signal: ac.signal,
       onListen: onListen(listeningPromise),
@@ -807,11 +824,12 @@ Deno.test(
     const listeningPromise = deferred();
     const ac = new AbortController();
 
-    const server = Deno.serve(async (request) => {
-      assertEquals(request.body, null);
-      promise.resolve();
-      return new Response(new Uint8Array([128]));
-    }, {
+    const server = Deno.serve({
+      fetch: async (request) => {
+        assertEquals(request.body, null);
+        promise.resolve();
+        return new Response(new Uint8Array([128]));
+      },
       port: 4501,
       signal: ac.signal,
       onListen: onListen(listeningPromise),
@@ -837,8 +855,7 @@ Deno.test("upgradeHttp tcp", async () => {
   const promise2 = deferred();
   const ac = new AbortController();
   const signal = ac.signal;
-
-  const server = Deno.serve(async (req) => {
+  const fetch = async (req: Request) => {
     const [conn, _] = await Deno.upgradeHttp(req);
 
     await conn.write(
@@ -856,7 +873,9 @@ Deno.test("upgradeHttp tcp", async () => {
 
     promise2.resolve();
     conn.close();
-  }, {
+  };
+  const server = Deno.serve({
+    fetch,
     port: 4501,
     signal,
     onListen: onListen(listeningPromise),
@@ -897,12 +916,13 @@ Deno.test(
     const listeningPromise = deferred();
     const ac = new AbortController();
 
-    const server = Deno.serve(async (request) => {
-      assertEquals(request.method, "GET");
-      assertEquals(request.headers.get("host"), "deno.land");
-      promise.resolve();
-      return new Response("ok");
-    }, {
+    const server = Deno.serve({
+      fetch: async (request) => {
+        assertEquals(request.method, "GET");
+        assertEquals(request.headers.get("host"), "deno.land");
+        promise.resolve();
+        return new Response("ok");
+      },
       port: 4503,
       signal: ac.signal,
       onListen: onListen(listeningPromise),
@@ -930,12 +950,13 @@ Deno.test(
     const listeningPromise = deferred();
     const ac = new AbortController();
 
-    const server = Deno.serve(async (request) => {
-      assertEquals(request.method, "GET");
-      assertEquals(request.headers.get("server"), "hello\tworld");
-      promise.resolve();
-      return new Response("ok");
-    }, {
+    const server = Deno.serve({
+      fetch: async (request) => {
+        assertEquals(request.method, "GET");
+        assertEquals(request.headers.get("server"), "hello\tworld");
+        promise.resolve();
+        return new Response("ok");
+      },
       port: 4503,
       signal: ac.signal,
       onListen: onListen(listeningPromise),
@@ -963,12 +984,13 @@ Deno.test(
     const listeningPromise = deferred();
     const ac = new AbortController();
 
-    const server = Deno.serve(async (request) => {
-      assertEquals(request.method, "GET");
-      assertEquals(await request.text(), "");
-      promise.resolve();
-      return new Response("ok");
-    }, {
+    const server = Deno.serve({
+      fetch: async (request) => {
+        assertEquals(request.method, "GET");
+        assertEquals(await request.text(), "");
+        promise.resolve();
+        return new Response("ok");
+      },
       port: 4503,
       signal: ac.signal,
       onListen: onListen(listeningPromise),
@@ -998,12 +1020,13 @@ Deno.test(
     const listeningPromise = deferred();
     const ac = new AbortController();
 
-    const server = Deno.serve(async (request) => {
-      assertEquals(request.method, "POST");
-      assertEquals(await request.text(), "I'm a good request.");
-      promise.resolve();
-      return new Response("ok");
-    }, {
+    const server = Deno.serve({
+      fetch: async (request) => {
+        assertEquals(request.method, "POST");
+        assertEquals(await request.text(), "I'm a good request.");
+        promise.resolve();
+        return new Response("ok");
+      },
       port: 4503,
       signal: ac.signal,
       onListen: onListen(listeningPromise),
@@ -1043,11 +1066,12 @@ function createServerLengthTest(name: string, testCase: TestCase) {
     const ac = new AbortController();
     const listeningPromise = deferred();
 
-    const server = Deno.serve(async (request) => {
-      assertEquals(request.method, "GET");
-      promise.resolve();
-      return new Response(testCase.body, testCase.headers ?? {});
-    }, {
+    const server = Deno.serve({
+      fetch: async (request) => {
+        assertEquals(request.method, "GET");
+        promise.resolve();
+        return new Response(testCase.body, testCase.headers ?? {});
+      },
       port: 4503,
       signal: ac.signal,
       onListen: onListen(listeningPromise),
@@ -1174,12 +1198,13 @@ Deno.test(
     const listeningPromise = deferred();
     const ac = new AbortController();
 
-    const server = Deno.serve(async (request) => {
-      assertEquals(request.method, "GET");
-      promises[reqCount].resolve();
-      reqCount++;
-      return new Response(reqCount <= 1 ? stream("foo bar baz") : "zar quux");
-    }, {
+    const server = Deno.serve({
+      fetch: async (request) => {
+        assertEquals(request.method, "GET");
+        promises[reqCount].resolve();
+        reqCount++;
+        return new Response(reqCount <= 1 ? stream("foo bar baz") : "zar quux");
+      },
       port: 4503,
       signal: ac.signal,
       onListen: onListen(listeningPromise),
@@ -1236,13 +1261,14 @@ Deno.test(
     const listeningPromise = deferred();
     const ac = new AbortController();
 
-    const server = Deno.serve(async (request) => {
-      assertEquals(request.method, "POST");
-      assertEquals(request.headers.get("content-length"), "5");
-      assertEquals(await request.text(), "hello");
-      promise.resolve();
-      return new Response("ok");
-    }, {
+    const server = Deno.serve({
+      fetch: async (request) => {
+        assertEquals(request.method, "POST");
+        assertEquals(request.headers.get("content-length"), "5");
+        assertEquals(await request.text(), "hello");
+        promise.resolve();
+        return new Response("ok");
+      },
       port: 4503,
       signal: ac.signal,
       onListen: onListen(listeningPromise),
@@ -1271,9 +1297,10 @@ Deno.test(
   async function httpServerPostWithInvalidPrefixContentLength() {
     const ac = new AbortController();
     const listeningPromise = deferred();
-    const server = Deno.serve(() => {
-      throw new Error("unreachable");
-    }, {
+    const server = Deno.serve({
+      fetch: () => {
+        throw new Error("unreachable");
+      },
       port: 4503,
       signal: ac.signal,
       onListen: onListen(listeningPromise),
@@ -1310,12 +1337,13 @@ Deno.test(
     const ac = new AbortController();
     const listeningPromise = deferred();
 
-    const server = Deno.serve(async (request) => {
-      assertEquals(request.method, "POST");
-      assertEquals(await request.text(), "qwert");
-      promise.resolve();
-      return new Response("ok");
-    }, {
+    const server = Deno.serve({
+      fetch: async (request) => {
+        assertEquals(request.method, "POST");
+        assertEquals(await request.text(), "qwert");
+        promise.resolve();
+        return new Response("ok");
+      },
       port: 4503,
       signal: ac.signal,
       onListen: onListen(listeningPromise),
@@ -1346,11 +1374,12 @@ Deno.test(
     const ac = new AbortController();
     const listeningPromise = deferred();
 
-    const server = Deno.serve(async (r) => {
-      promise.resolve();
-      assertEquals(await r.text(), "12345");
-      return new Response("ok");
-    }, {
+    const server = Deno.serve({
+      fetch: async (r) => {
+        promise.resolve();
+        assertEquals(await r.text(), "12345");
+        return new Response("ok");
+      },
       port: 4503,
       signal: ac.signal,
       onListen: onListen(listeningPromise),
@@ -1381,10 +1410,11 @@ Deno.test(
     const ac = new AbortController();
     const listeningPromise = deferred();
 
-    const server = Deno.serve(() => {
-      promise.resolve();
-      return new Response("foo bar baz");
-    }, {
+    const server = Deno.serve({
+      fetch: () => {
+        promise.resolve();
+        return new Response("foo bar baz");
+      },
       port: 4503,
       signal: ac.signal,
       onListen: onListen(listeningPromise),
@@ -1428,11 +1458,12 @@ Deno.test(
     const data = new Uint8Array(70 * 1024).fill(1);
     await file.write(data);
     file.close();
-    const server = Deno.serve(async () => {
-      const f = await Deno.open(tmpFile, { read: true });
-      promise.resolve();
-      return new Response(f.readable, { status: 200 });
-    }, {
+    const server = Deno.serve({
+      fetch: async () => {
+        const f = await Deno.open(tmpFile, { read: true });
+        promise.resolve();
+        return new Response(f.readable, { status: 200 });
+      },
       port: 4503,
       signal: ac.signal,
       onListen: onListen(listeningPromise),
@@ -1462,11 +1493,12 @@ Deno.test(
     await file.write(data);
     file.close();
 
-    const server = Deno.serve(async (request) => {
-      assertEquals(new Uint8Array(await request.arrayBuffer()), data);
-      promise.resolve();
-      return new Response("ok");
-    }, {
+    const server = Deno.serve({
+      fetch: async (request) => {
+        assertEquals(new Uint8Array(await request.arrayBuffer()), data);
+        promise.resolve();
+        return new Response("ok");
+      },
       port: 4503,
       signal: ac.signal,
       onListen: onListen(listeningPromise),
@@ -1497,11 +1529,9 @@ Deno.test(
     const listeningPromise = deferred();
     const hostname = "127.0.0.1";
     const port = 4501;
-    function handler() {
-      return new Response("Hello World");
-    }
 
-    const server = Deno.serveTls(handler, {
+    const server = Deno.serve({
+      fetch: () => new Response("Hello World"),
       hostname,
       port,
       signal: ac.signal,
@@ -1535,11 +1565,12 @@ Deno.test(
     const listeningPromise = deferred();
     const promise = deferred();
 
-    const server = Deno.serve(async (req) => {
-      assertEquals(await req.text(), "");
-      promise.resolve();
-      return new Response("ok");
-    }, {
+    const server = Deno.serve({
+      fetch: async (req) => {
+        assertEquals(await req.text(), "");
+        promise.resolve();
+        return new Response("ok");
+      },
       port: 4503,
       signal: ac.signal,
       onListen: onListen(listeningPromise),
@@ -1569,9 +1600,10 @@ Deno.test(
     const ac = new AbortController();
     const listeningPromise = deferred();
 
-    const server = Deno.serve(() => {
-      throw new Error("oops");
-    }, {
+    const server = Deno.serve({
+      fetch: () => {
+        throw new Error("oops");
+      },
       port: 4503,
       signal: ac.signal,
       onListen: onListen(listeningPromise),
@@ -1617,10 +1649,11 @@ Deno.test(
     const ac = new AbortController();
     const listeningPromise = deferred();
 
-    const server = Deno.serve(() => {
-      promise.resolve();
-      return new Response(null, { status: 304 });
-    }, {
+    const server = Deno.serve({
+      fetch: () => {
+        promise.resolve();
+        return new Response(null, { status: 304 });
+      },
       port: 4503,
       signal: ac.signal,
       onListen: onListen(listeningPromise),
@@ -1660,11 +1693,12 @@ Deno.test(
     const ac = new AbortController();
     const listeningPromise = deferred();
 
-    const server = Deno.serve(async (req) => {
-      promise.resolve();
-      assertEquals(await req.text(), "hello");
-      return new Response(null, { status: 304 });
-    }, {
+    const server = Deno.serve({
+      fetch: async (req) => {
+        promise.resolve();
+        assertEquals(await req.text(), "hello");
+        return new Response(null, { status: 304 });
+      },
       port: 4503,
       signal: ac.signal,
       onListen: onListen(listeningPromise),
@@ -1720,11 +1754,12 @@ Deno.test(
     const listeningPromise = deferred();
     const ac = new AbortController();
 
-    const server = Deno.serve(async (req) => {
-      promise.resolve();
-      assertEquals(await req.text(), "");
-      return new Response(null, { status: 304 });
-    }, {
+    const server = Deno.serve({
+      fetch: async (req) => {
+        promise.resolve();
+        assertEquals(await req.text(), "");
+        return new Response(null, { status: 304 });
+      },
       port: 4503,
       signal: ac.signal,
       onListen: onListen(listeningPromise),
@@ -1773,9 +1808,10 @@ for (const [name, req] of badRequests) {
       const ac = new AbortController();
       const listeningPromise = deferred();
 
-      const server = Deno.serve(() => {
-        throw new Error("oops");
-      }, {
+      const server = Deno.serve({
+        fetch: () => {
+          throw new Error("oops");
+        },
         port: 4503,
         signal: ac.signal,
         onListen: onListen(listeningPromise),
@@ -1817,7 +1853,8 @@ Deno.test(
     const ac = new AbortController();
     const listeningPromise = deferred();
 
-    const server = Deno.serve(() => new Response(null), {
+    const server = Deno.serve({
+      fetch: () => new Response(null),
       port: 4503,
       signal: ac.signal,
       onListen: onListen(listeningPromise),
@@ -1856,32 +1893,33 @@ Deno.test(
 
     let reqCount = -1;
     let timerId: number | undefined;
-    const server = Deno.serve(async (req) => {
-      reqCount++;
-      if (reqCount === 0) {
-        const msg = new TextEncoder().encode("data: hello\r\n\r\n");
-        // SSE
-        const body = new ReadableStream({
-          start(controller) {
-            timerId = setInterval(() => {
-              controller.enqueue(msg);
-            }, 1000);
-          },
-          cancel() {
-            if (typeof timerId === "number") {
-              clearInterval(timerId);
-            }
-          },
-        });
-        return new Response(body, {
-          headers: {
-            "Content-Type": "text/event-stream",
-          },
-        });
-      }
+    const server = Deno.serve({
+      fetch: async (req) => {
+        reqCount++;
+        if (reqCount === 0) {
+          const msg = new TextEncoder().encode("data: hello\r\n\r\n");
+          // SSE
+          const body = new ReadableStream({
+            start(controller) {
+              timerId = setInterval(() => {
+                controller.enqueue(msg);
+              }, 1000);
+            },
+            cancel() {
+              if (typeof timerId === "number") {
+                clearInterval(timerId);
+              }
+            },
+          });
+          return new Response(body, {
+            headers: {
+              "Content-Type": "text/event-stream",
+            },
+          });
+        }
 
-      return new Response(`hello ${reqCount}`);
-    }, {
+        return new Response(`hello ${reqCount}`);
+      },
       port: 4503,
       signal: ac.signal,
       onListen: onListen(listeningPromise),
diff --git a/ext/flash/01_http.js b/ext/flash/01_http.js
index 19920da58..d850a1520 100644
--- a/ext/flash/01_http.js
+++ b/ext/flash/01_http.js
@@ -185,18 +185,19 @@
     return hostname === "0.0.0.0" ? "localhost" : hostname;
   }
 
-  function serve(handler, opts = {}) {
-    delete opts.key;
-    delete opts.cert;
-    return serveInner(handler, opts, false);
-  }
-
-  function serveTls(handler, opts = {}) {
-    return serveInner(handler, opts, true);
-  }
-
-  function serveInner(handler, opts, useTls) {
-    opts = { hostname: "127.0.0.1", port: 9000, useTls, ...opts };
+  function serve(opts = {}) {
+    if (!("fetch" in opts)) {
+      throw new TypeError("Options is missing 'fetch' handler");
+    }
+    if ("cert" in opts && !("key" in opts)) {
+      throw new TypeError("Options is missing 'key' field");
+    }
+    if ("key" in opts && !("cert" in opts)) {
+      throw new TypeError("Options is missing 'cert' field");
+    }
+    opts = { hostname: "127.0.0.1", port: 9000, ...opts };
+    const handler = opts.fetch;
+    delete opts.fetch;
     const signal = opts.signal;
     delete opts.signal;
     const onError = opts.onError ?? function (error) {
@@ -570,6 +571,5 @@
 
   window.__bootstrap.flash = {
     serve,
-    serveTls,
   };
 })(this);
diff --git a/ext/flash/README.md b/ext/flash/README.md
index 465c60d47..bc3c12065 100644
--- a/ext/flash/README.md
+++ b/ext/flash/README.md
@@ -3,5 +3,5 @@
 Flash is a fast HTTP/1.1 server implementation for Deno.
 
 ```js
-serve((req) => new Response("Hello World"));
+serve({ fetch: (req) => new Response("Hello World") });
 ```
diff --git a/ext/flash/lib.rs b/ext/flash/lib.rs
index 8f3cb341a..abd8502d0 100644
--- a/ext/flash/lib.rs
+++ b/ext/flash/lib.rs
@@ -935,7 +935,6 @@ pub struct ListenOpts {
   key: Option<String>,
   hostname: String,
   port: u16,
-  use_tls: bool,
 }
 
 fn run_server(
@@ -1239,11 +1238,7 @@ fn op_flash_serve<P>(
 where
   P: FlashPermissions + 'static,
 {
-  if opts.use_tls {
-    check_unstable(state, "Deno.serveTls");
-  } else {
-    check_unstable(state, "Deno.serve");
-  }
+  check_unstable(state, "Deno.serve");
   state
     .borrow_mut::<P>()
     .check_net(&(&opts.hostname, Some(opts.port)))?;
diff --git a/runtime/js/90_deno_ns.js b/runtime/js/90_deno_ns.js
index b97c05556..dfca9d5bc 100644
--- a/runtime/js/90_deno_ns.js
+++ b/runtime/js/90_deno_ns.js
@@ -154,6 +154,5 @@
     spawn: __bootstrap.spawn.spawn,
     spawnSync: __bootstrap.spawn.spawnSync,
     serve: __bootstrap.flash.serve,
-    serveTls: __bootstrap.flash.serveTls,
   };
 })(this);