First pass

echo-server.mjs

@@ -0,0 +1,25 @@
+import { WebSocketServer } from "ws";
+
+const port = 8989;
+const wss = new WebSocketServer({ port: port });
+
+console.log("listening on port: " + port);
+
+wss.on("connection", function connection(ws) {
+  ws.on("message", function (message) {
+    console.log("message: " + message);
+    ws.send(
+      JSON.stringify({
+        date: Date.now(),
+        author: "ECHO Service",
+        content: message.toString("utf-8"),
+      })
+    );
+  });
+  ws.on("close", function close() {
+    console.log("closed a connection");
+  });
+
+  console.log("new client connected!");
+  ws.send("connected!");
+});

next-env.d.ts

@@ -1,3 +1,6 @@
 /// <reference types="next" />
 /// <reference types="next/types/global" />
 /// <reference types="next/image-types/global" />
+
+// NOTE: This file should not be edited
+// see https://nextjs.org/docs/basic-features/typescript for more information.

package.json

@@ -21,6 +21,7 @@
     "@types/react": "^17.0.13",
     "next": "^11.0.1",
     "preact": "^10.5.14",
+    "react-use-websocket": "^2.9.1",
     "typescript": "^4.3.5"
   },
   "devDependencies": {
@@ -38,7 +39,8 @@
     "pre-commit": "^1.2.2",
     "prettier": "^2.3.2",
     "react": "^17.0.2",
-    "react-dom": "^17.0.2"
+    "react-dom": "^17.0.2",
+    "ws": "^8.4.0"
   },
   "pre-commit": "test",
   "license": "MIT"

src/pages/404.tsx

@@ -1,3 +0,0 @@
-export default function NotFound(): JSX.Element {
-  return <>404</>;
-}

src/pages/index.tsx

@@ -1,56 +1,91 @@
-import Image from "next/image";
-import { useState } from "react";
+import { useCallback, useState } from "react";
+import useWebSocket, {
+  ReadyState as WebSocketReadyState,
+} from "react-use-websocket";
+
+import type { Message } from "../util/types/Message";
+
 export default function Index(): JSX.Element {
   const [count, setCount] = useState(0);
+  const [messageHistory, setMessageHistory] = useState<Message[]>([]);
+  const [socketUrl, setSocketUrl] = useState(
+    "wss://toby222-web-drs-4gjg49gj355qq-8989.githubpreview.dev/"
+  );
+
+  function onMessage(event: MessageEvent<string>): void {
+    const message: Message = JSON.parse(event.data);
+
+    setMessageHistory([message, ...messageHistory]);
+  }
+
+  const websocket = useWebSocket(socketUrl, {
+    onMessage,
+  });
+
+  const handleClickSendMessage = useCallback(() => {
+    setCount(count + 1);
+    websocket.sendMessage(`${count + 1}`);
+  }, [count, websocket]);
+
+  const connectionStatus = {
+    [WebSocketReadyState.CONNECTING]: "Connecting",
+    [WebSocketReadyState.OPEN]: "Open",
+    [WebSocketReadyState.CLOSING]: "Closing",
+    [WebSocketReadyState.CLOSED]: "Closed",
+    [WebSocketReadyState.UNINSTANTIATED]: "Uninstantiated",
+  }[websocket.readyState];
+
+  function trySetSocketUrl(url: string) {
+    try {
+      console.log(new URL("wss:" + url), url);
+      setSocketUrl("wss:" + url);
+    } catch (e) {
+      // Invalid URL, don't do anything
+    } finally {
+      websocket.getWebSocket()?.close();
+    }
+  }
 
   return (
     <>
-      <header className="app-header">
-        {" "}
-        <Image
-          src={require("../util/logo.svg")}
-          className="logo"
-          alt="logo"
-          width={350}
-          height={265}
-        />
-        <p className="header">
-          Next.js + Preact + Typescript <br />
-          & <br />
-          Eslint + Prettier
-        </p>
-        <div className="content">
-          <button
-            onClick={() => setCount(count + 1)}
-            style={{ cursor: "pointer" }}
-          >
-            Click me: {count}
-          </button>
-          <p>
-            Don&apos;t forget to install ESlint and Prettier integration in your
-            IDE.
-          </p>
-          <p>
-            <a
-              className="link"
-              href="https://preactjs.com/"
-              target="_blank"
-              rel="noopener noreferrer"
-            >
-              Learn Preact
-            </a>
-            {" | "}
-            <a
-              className="link"
-              href="https://nextjs.org/docs"
-              target="_blank"
-              rel="noopener noreferrer"
-            >
-              Next.js Documentation
-            </a>
-          </p>
+      <main>
+        {/* DEBUG
+        <div>
+          <h4>Last messages:</h4>
+          {websocket.lastMessage?.data.toString() ?? "No message received"}
+          <hr />
+          <h4>Ready state:</h4>
+          {connectionStatus} ({websocket.readyState})
         </div>
-      </header>
+        */}
+        <ol>
+          {messageHistory.map((message, idx) => {
+            return (
+              <span key={messageHistory.length - idx}>
+                <span>{new Date(message.date).toISOString()}</span>
+                {" - "}
+                <span>{message.content}</span>
+                <br />
+              </span>
+            );
+          })}
+        </ol>
+        <div>
+          <label htmlFor="ws-url">WebSocket URL:</label>
+          <input
+            id="ws-url"
+            type={"text"}
+            value={socketUrl.replace(/wss:(?:\/\/)?/, "")}
+            onChange={(e) => trySetSocketUrl(e.target.value)}
+          />
+          <button
+            disabled={websocket.readyState !== WebSocketReadyState.OPEN}
+            onClick={handleClickSendMessage}
+          >
+            Click to send message.
+          </button>
+        </div>
+      </main>
     </>
   );
 }

src/pages/styles.css

@@ -6,32 +6,26 @@
   text-align: center;
 }
 
-.logo {
-  height: 40vmin;
-  pointer-events: none;
-}
-
 p {
   margin: 20px 0px;
 }
 
-.header {
-  font-size: 3rem;
-}
-
-.content {
-  margin: 20px 0 10px;
-  font-size: 0.9rem;
-}
-
 button {
   outline: none;
   border: none;
-  border-radius: 8px;
+  border-radius: 0;
   padding: 10px 35px;
 
   background: #845ec2;
   color: white;
+  /* font-size: calc(10px + 2vmin); */
+}
+button:disabled {
+  filter: brightness(30%);
+}
+button:hover {
+  filter: brightness(120%);
+  cursor: pointer;
 }
 
 @media (prefers-reduced-motion: no-preference) {
@@ -66,10 +60,6 @@ button {
   }
 }
 
-button {
-  font-size: calc(10px + 2vmin);
-}
-
 body {
   margin: 0;
   font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Roboto", "Oxygen",

src/util/logo.svg

@@ -1 +0,0 @@
-<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 841.9 595.3"><g fill="#61DAFB"><path d="M666.3 296.5c0-32.5-40.7-63.3-103.1-82.4 14.4-63.6 8-114.2-20.2-130.4-6.5-3.8-14.1-5.6-22.4-5.6v22.3c4.6 0 8.3.9 11.4 2.6 13.6 7.8 19.5 37.5 14.9 75.7-1.1 9.4-2.9 19.3-5.1 29.4-19.6-4.8-41-8.5-63.5-10.9-13.5-18.5-27.5-35.3-41.6-50 32.6-30.3 63.2-46.9 84-46.9V78c-27.5 0-63.5 19.6-99.9 53.6-36.4-33.8-72.4-53.2-99.9-53.2v22.3c20.7 0 51.4 16.5 84 46.6-14 14.7-28 31.4-41.3 49.9-22.6 2.4-44 6.1-63.6 11-2.3-10-4-19.7-5.2-29-4.7-38.2 1.1-67.9 14.6-75.8 3-1.8 6.9-2.6 11.5-2.6V78.5c-8.4 0-16 1.8-22.6 5.6-28.1 16.2-34.4 66.7-19.9 130.1-62.2 19.2-102.7 49.9-102.7 82.3 0 32.5 40.7 63.3 103.1 82.4-14.4 63.6-8 114.2 20.2 130.4 6.5 3.8 14.1 5.6 22.5 5.6 27.5 0 63.5-19.6 99.9-53.6 36.4 33.8 72.4 53.2 99.9 53.2 8.4 0 16-1.8 22.6-5.6 28.1-16.2 34.4-66.7 19.9-130.1 62-19.1 102.5-49.9 102.5-82.3zm-130.2-66.7c-3.7 12.9-8.3 26.2-13.5 39.5-4.1-8-8.4-16-13.1-24-4.6-8-9.5-15.8-14.4-23.4 14.2 2.1 27.9 4.7 41 7.9zm-45.8 106.5c-7.8 13.5-15.8 26.3-24.1 38.2-14.9 1.3-30 2-45.2 2-15.1 0-30.2-.7-45-1.9-8.3-11.9-16.4-24.6-24.2-38-7.6-13.1-14.5-26.4-20.8-39.8 6.2-13.4 13.2-26.8 20.7-39.9 7.8-13.5 15.8-26.3 24.1-38.2 14.9-1.3 30-2 45.2-2 15.1 0 30.2.7 45 1.9 8.3 11.9 16.4 24.6 24.2 38 7.6 13.1 14.5 26.4 20.8 39.8-6.3 13.4-13.2 26.8-20.7 39.9zm32.3-13c5.4 13.4 10 26.8 13.8 39.8-13.1 3.2-26.9 5.9-41.2 8 4.9-7.7 9.8-15.6 14.4-23.7 4.6-8 8.9-16.1 13-24.1zM421.2 430c-9.3-9.6-18.6-20.3-27.8-32 9 .4 18.2.7 27.5.7 9.4 0 18.7-.2 27.8-.7-9 11.7-18.3 22.4-27.5 32zm-74.4-58.9c-14.2-2.1-27.9-4.7-41-7.9 3.7-12.9 8.3-26.2 13.5-39.5 4.1 8 8.4 16 13.1 24 4.7 8 9.5 15.8 14.4 23.4zM420.7 163c9.3 9.6 18.6 20.3 27.8 32-9-.4-18.2-.7-27.5-.7-9.4 0-18.7.2-27.8.7 9-11.7 18.3-22.4 27.5-32zm-74 58.9c-4.9 7.7-9.8 15.6-14.4 23.7-4.6 8-8.9 16-13 24-5.4-13.4-10-26.8-13.8-39.8 13.1-3.1 26.9-5.8 41.2-7.9zm-90.5 125.2c-35.4-15.1-58.3-34.9-58.3-50.6 0-15.7 22.9-35.6 58.3-50.6 8.6-3.7 18-7 27.7-10.1 5.7 19.6 13.2 40 22.5 60.9-9.2 20.8-16.6 41.1-22.2 60.6-9.9-3.1-19.3-6.5-28-10.2zM310 490c-13.6-7.8-19.5-37.5-14.9-75.7 1.1-9.4 2.9-19.3 5.1-29.4 19.6 4.8 41 8.5 63.5 10.9 13.5 18.5 27.5 35.3 41.6 50-32.6 30.3-63.2 46.9-84 46.9-4.5-.1-8.3-1-11.3-2.7zm237.2-76.2c4.7 38.2-1.1 67.9-14.6 75.8-3 1.8-6.9 2.6-11.5 2.6-20.7 0-51.4-16.5-84-46.6 14-14.7 28-31.4 41.3-49.9 22.6-2.4 44-6.1 63.6-11 2.3 10.1 4.1 19.8 5.2 29.1zm38.5-66.7c-8.6 3.7-18 7-27.7 10.1-5.7-19.6-13.2-40-22.5-60.9 9.2-20.8 16.6-41.1 22.2-60.6 9.9 3.1 19.3 6.5 28.1 10.2 35.4 15.1 58.3 34.9 58.3 50.6-.1 15.7-23 35.6-58.4 50.6zM320.8 78.4z"/><circle cx="420.9" cy="296.5" r="45.7"/><path d="M520.5 78.1z"/></g></svg>

src/util/types/Message.ts

@@ -0,0 +1,5 @@
+export type Message = {
+  author: string;
+  content: string;
+  date: number;
+};