import { WebSocketServer } from "https://deno.land/x/ayonli_jsext@v0.9.72/esm/ws.js";
A unified WebSocket server interface for Node.js, Deno, Bun and Cloudflare Workers.
There are two ways to handle WebSocket connections:
- By passing a listener function to the constructor, handle all connections in a central place.
- By using the
socketobject returned from theupgrademethod to handle each connection in a more flexible way. However, at this stage, the connection may not be ready yet, and we need to listen theopenevent or wait for thereadypromise (deprecated) to resolve before we can start sending messages.
The socket object is an async iterable object, which can be used in the
for await...of loop to read messages with backpressure support.
Examples
Example 1
Example 1
// centralized connection handler
import { WebSocketServer } from "@ayonli/jsext/ws";
const wsServer = new WebSocketServer(socket => {
console.log("WebSocket connection established.");
socket.addEventListener("message", (event) => {
socket.send("received: " + event.data);
});
socket.addEventListener("error", (event) => {
console.error("WebSocket connection error:", event.error);
});
socket.addEventListener("close", (event) => {
console.log(`WebSocket connection closed, reason: ${event.reason}, code: ${event.code}`);
});
});
// Node.js
import * as http from "node:http";
const httpServer = http.createServer(req => {
wsServer.upgrade(req);
});
httpServer.listen(3000);
// Node.js (withWeb)
import { withWeb } from "@ayonli/jsext/http";
const httpServer2 = http.createServer(withWeb(req => {
const { response } = wsServer.upgrade(req);
return response;
}));
httpServer2.listen(3001);
// Bun
const bunServer = Bun.serve({
fetch(req) {
const { response } = wsServer.upgrade(req);
return response;
},
websocket: wsServer.bunListener,
});
wsServer.bunBind(bunServer);
// Deno
Deno.serve(req => {
const { response } = wsServer.upgrade(req);
return response;
});
// Cloudflare Workers
export default {
fetch(req) {
const { response } = wsServer.upgrade(req);
return response;
},
};
Example 2
Example 2
// per-request connection handler (Deno example)
import { WebSocketServer } from "@ayonli/jsext/ws";
const wsServer = new WebSocketServer();
Deno.serve(req => {
const { socket, response } = wsServer.upgrade(req);
socket.addEventListener("open", () => {
console.log("WebSocket connection established.");
});
socket.addEventListener("message", (event) => {
socket.send("received: " + event.data);
});
socket.addEventListener("error", (event) => {
console.error("WebSocket connection error:", event.error);
});
socket.addEventListener("close", (event) => {
console.log(`WebSocket connection closed, reason: ${event.reason}, code: ${event.code}`);
});
// The response should be returned immediately, otherwise the web socket
// will not be ready.
return response;
});
Example 3
Example 3
// async iterable
const wsServer = new WebSocketServer(async socket => {
console.log("WebSocket connection established.");
try {
for await (const message of socket) {
socket.send("received: " + message);
}
} catch (error) {
console.error("WebSocket connection error:", error);
}
console.log("WebSocket connection closed");
});
Deno.serve(req => {
const { response } = wsServer.upgrade(req);
return response;
});