bun-pub_sub-test

This is a test of the pub/sub functionality of bun.

Its just the example from the bun docs, but with a few extra lines to make it work.

I added some console logs to the index.ts file to understand how it works.

Findings:

• You must be subscribed to a channel to be able to publish via ws.publish(channel, msg).
• Your own Websocket will not receive the message you publish via ws.publish(channel, msg).
  • Make sure to display the message for yourself as well if you want to see it.
• To publish a message without being subscribed, use server.publish(channel, msg). (I think this might even be a bug, but its good that its there.)
• Use server.publish(channel, msg) to send a message to all subscribers of a channel.
  • This works even if you are not subscribed to the channel yourself.

Try it out

Try it in web console with

let ws1 = new WebSocket("ws://localhost:3000");
let ws2 = new WebSocket("ws://localhost:3000");
let ws3 = new WebSocket("ws://localhost:3000");
ws1.onmessage = (e) => console.log(`Websocket 1: ${e.data}`);
ws2.onmessage = (e) => console.log(`Websocket 2: ${e.data}`);
ws3.onmessage = (e) => console.log(`Websocket 2: ${e.data}`);

setTimeout(() => ws1.send("Hello from Websocket1"), 1000);
setTimeout(() => ws2.send("Hello from Websocket2"), 2000);
setTimeout(() => ws3.send("Hello from Websocket3"), 3000);

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To install dependencies:

bun install

To run:

bun run index.ts

This project was created using bun init in bun v1.0.4. Bun is a fast all-in-one JavaScript runtime.