feat!: move from WebSockets to SSE

Reasons:
- We need only one directional channel
- SSE easier to proxy
- we can use only one port for app

.npmrc

@@ -0,0 +1 @@
+@radioiceberg:registry=https://gitea.bjornmossa.net/api/packages/Radioiceberg/npm/

Dockerfile

@@ -5,5 +5,5 @@ COPY package*.json ./
 RUN npm ci --omit=dev
 COPY src/. .
 
-EXPOSE 4000 7000
+EXPOSE 4000
 CMD [ "node", "main.js" ]

Makefile

@@ -11,6 +11,9 @@ start:
 build:
 	docker build . -t $(IMAGE_NAME):$(GIT_TAG)
 
+build-experimental:
+	docker build . -t $(IMAGE_NAME):experimental
+
 bump-latest:
 	docker tag $(IMAGE_NAME):$(GIT_TAG) $(IMAGE_NAME):latest
 

package-lock.json

@@ -9,36 +9,21 @@
       "version": "1.0.0",
       "license": "GPL-3.0-or-later",
       "dependencies": {
-        "ws": "^8.13.0"
+        "@radioiceberg/message-processor": "^0.0.1"
       }
     },
-    "node_modules/ws": {
+    "node_modules/@radioiceberg/message-processor": {
-      "version": "8.14.2",
+      "version": "0.0.1",
-      "resolved": "https://registry.npmjs.org/ws/-/ws-8.14.2.tgz",
+      "resolved": "https://gitea.bjornmossa.net/api/packages/Radioiceberg/npm/%40radioiceberg%2Fmessage-processor/-/0.0.1/message-processor-0.0.1.tgz",
-      "integrity": "sha512-wEBG1ftX4jcglPxgFCMJmZ2PLtSbJ2Peg6TmpJFTbe9GZYOQCDPdMYu/Tm0/bGZkw8paZnJY45J4K2PZrLYq8g==",
+      "integrity": "sha512-6hfnRGOXisOZCBueS1wYExFopMiK7Ig+UplP9pJQH7kWPmlnSFE33G0cU/gBuCUrS3v81uDJ8FGBse6H88dptw==",
-      "engines": {
+      "license": "GPL-3.0-or-later"
-        "node": ">=10.0.0"
-      },
-      "peerDependencies": {
-        "bufferutil": "^4.0.1",
-        "utf-8-validate": ">=5.0.2"
-      },
-      "peerDependenciesMeta": {
-        "bufferutil": {
-          "optional": true
-        },
-        "utf-8-validate": {
-          "optional": true
-        }
-      }
     }
   },
   "dependencies": {
-    "ws": {
+    "@radioiceberg/message-processor": {
-      "version": "8.14.2",
+      "version": "0.0.1",
-      "resolved": "https://registry.npmjs.org/ws/-/ws-8.14.2.tgz",
+      "resolved": "https://gitea.bjornmossa.net/api/packages/Radioiceberg/npm/%40radioiceberg%2Fmessage-processor/-/0.0.1/message-processor-0.0.1.tgz",
-      "integrity": "sha512-wEBG1ftX4jcglPxgFCMJmZ2PLtSbJ2Peg6TmpJFTbe9GZYOQCDPdMYu/Tm0/bGZkw8paZnJY45J4K2PZrLYq8g==",
+      "integrity": "sha512-6hfnRGOXisOZCBueS1wYExFopMiK7Ig+UplP9pJQH7kWPmlnSFE33G0cU/gBuCUrS3v81uDJ8FGBse6H88dptw=="
-      "requires": {}
     }
   }
 }

package.json

@@ -18,6 +18,6 @@
   },
   "homepage": "https://github.com/Arseniusz/radioiceberg#readme",
   "dependencies": {
-    "ws": "^8.13.0"
+    "@radioiceberg/message-processor": "^0.0.1"
   }
 }

src/actions.js

@@ -0,0 +1,25 @@
+import { events, eventsStream } from "./events-stream.js";
+import { state } from "./state.js";
+
+function metadataChange(data) {
+  state.lastPlayed = data;
+  eventsStream.emit(events.stateChange, { action: "metadataChange", data });
+}
+
+function liveStarted() {
+  state.isOnline = true;
+  eventsStream.emit(events.stateChange, { action: "liveStarted" });
+}
+
+function liveEnded() {
+  state.isOnline = false;
+  eventsStream.emit(events.stateChange, { action: "liveEnded" });
+}
+
+const actions = {
+  metadataChange,
+  liveStarted,
+  liveEnded,
+};
+
+export { actions };

src/events-stream.js

@@ -0,0 +1,11 @@
+import { EventEmitter } from "events";
+
+class EventStream extends EventEmitter {}
+
+const events = Object.freeze({
+  stateChange: "stateChange",
+});
+
+const eventsStream = new EventStream();
+
+export { eventsStream, events };

src/main.js

@@ -1,49 +1,24 @@
 import { createServer } from "node:http";
-import { randomUUID } from "node:crypto";
+import { actions } from "./actions.js";
-import { WebSocketServer } from "ws";
+import { parse } from "node:url";
-import { notifier } from "./notifier.js";
+import { routes } from "./routes/index.js";
+import { messageProcessor } from "@radioiceberg/message-processor";
 
-const wss = new WebSocketServer({ port: 7000 });
+messageProcessor.actions = actions;
-
-wss.on("connection", (ws) => {
-  const id = randomUUID();
-  const message = {
-    action: "clientConnected",
-    data: {
-      socket: ws,
-      id,
-    },
-  };
-
-  notifier.processMessage(message);
-
-  ws.on("close", () => {
-    const message = {
-      action: "cliendDisconnected",
-      data: {
-        id,
-      },
-    };
-
-    notifier.processMessage(message);
-  });
-});
 
 createServer((req, res) => {
-  let body = "";
+  if (!req.url) res.end();
+
+  var url = parse(req.url);
+  var path = url.pathname.replace(/^\/+|\/$/g, "").toLowerCase();
+  var data = "";
 
   req.on("data", (chunk) => {
-    body += chunk;
+    data += chunk;
   });
 
   req.on("end", () => {
-    try {
+    var route = routes[path] ?? routes["notFound"];
-      const message = JSON.parse(body);
+    return route(req, res, data);
-      notifier.processMessage(message);
-    } catch (error) {
-      console.error(error);
-    }
   });
-
-  res.end();
 }).listen(4000);

src/notifier.js

@@ -1,60 +0,0 @@
-import { state } from "./state.js";
-
-function updateMeta(message) {
-  const { data } = message;
-  this.state.lastPlayed = data;
-  this.notifyAll(message);
-}
-
-function startOnline(message) {
-  this.state.isOnline = true;
-  this.notifyAll(message);
-}
-
-function stopOnline(message) {
-  this.state.isOnline = false;
-  this.notifyAll(message);
-}
-
-function addClient({ data }) {
-  const { socket, id } = data;
-  this.clients.set(id, socket);
-  this.notifyOne(socket, { action: "setState", data: this.state });
-}
-
-function deleteClient({ data }) {
-  const { id } = data;
-  this.clients.delete(id);
-}
-
-const actions = {
-  clientConnected: addClient,
-  cliendDisconnected: deleteClient,
-  metadataChange: updateMeta,
-  liveStarted: startOnline,
-  liveEnded: stopOnline,
-};
-
-const notifier = {
-  __proto__: state,
-  notifyAll: function (message) {
-    const messageStrinified = JSON.stringify(message);
-    this.clients.forEach((c) => c.send(messageStrinified));
-  },
-  notifyOne: function (socket, message) {
-    const messageStrinified = JSON.stringify(message);
-    console.log("NOTIFY ONE:", message);
-    socket.send(messageStrinified);
-  },
-  processMessage: function (message) {
-    const action = actions[message.action];
-    if (action) {
-      action.call(this, message);
-      console.log("PERFORM ACTION", message.action);
-    } else {
-      console.log("no avaible command for state mutation", message.action);
-    }
-  },
-};
-
-export { notifier };

src/routes/index.js

@@ -0,0 +1,11 @@
+import { notFound } from "./notfound.js";
+import { post } from "./post.js";
+import { liveData } from "./livedata.js";
+
+const routes = {
+  livedata: liveData,
+  post,
+  notFound,
+};
+
+export { routes };

src/routes/livedata.js

@@ -0,0 +1,25 @@
+import { state } from "../state.js";
+import { events, eventsStream } from "../events-stream.js";
+import { SSE } from "../sse.js";
+
+/**
+ * @param {import('http').ServerResponse} res somebody Somebody's name.
+ */
+function liveData(req, res) {
+  const sse = new SSE(res);
+
+  // Client connected. Send last saved state
+  const startupMessage = {
+    action: "setState",
+    data: state,
+  };
+
+  sse.send(startupMessage);
+
+  // Subscribe on events update and send it to client
+  eventsStream.on(events.stateChange, (data) => {
+    sse.send(data);
+  });
+}
+
+export { liveData };

src/routes/notfound.js

@@ -0,0 +1,9 @@
+/**
+ * @param {import('http').ServerResponse} res somebody Somebody's name.
+ */
+function notFound(_, res) {
+  res.writeHead(404);
+  res.end();
+}
+
+export { notFound };

src/routes/post.js

@@ -0,0 +1,13 @@
+import { messageProcessor } from "@radioiceberg/message-processor";
+
+/**
+ * @param {import('http').ServerResponse} res somebody Somebody's name.
+ * @param {string} data possibly transformable to json string data.
+ */
+function post(_, res, data) {
+  messageProcessor.processMessage(data);
+  res.writeHead(202);
+  res.end();
+}
+
+export { post };

src/sse.js

@@ -0,0 +1,27 @@
+import { EOL } from "os";
+
+class SSE {
+  /**
+   * @param {import('http').ServerResponse} res somebody Somebody's name.
+   */
+  constructor(res) {
+    res.setHeader("Content-Type", "text/event-stream");
+    res.setHeader("Cache-Control", "no-cache");
+    res.setHeader("Connection", "keep-alive");
+
+    this.res = res;
+    this.id = 0;
+  }
+
+  send(data) {
+    try {
+      this.res.write(`id: ${++this.id}${EOL}`);
+      this.res.write(`data: ${JSON.stringify(data)}${EOL}`);
+      this.res.write(`${EOL}`);
+    } catch (e) {
+      console.error("Can not send SSE event", e);
+    }
+  }
+}
+
+export { SSE };

src/state.js

@@ -1,9 +1,6 @@
 const state = {
-  state: {
+  lastPlayed: null,
-    lastPlayed: null,
+  isOnline: false,
-    isOnline: false,
-  },
-  clients: new Map(),
 };
 
 export { state };