sse-channels

Server-Sent Events middleware

Install

npm install --save @dropb/sse-channels

Usage

const { SseChannels } = require('@dropb/sse-channels');
const express = require('express');
const { join } = require('path');

const app = express();
app.get('/', (req, res) => {
  res.sendFile(join(`${__dirname}/index.html`));
});
const sse = new SseChannels();
sse.on('connected', (client) => {
  sse.send('message', `+++ ${client.req.query.ch} connected`);
});
sse.on('disconnected', (client) => {
  sse.send('message', `--- ${client.req.query.ch} disconnected`);
});
app.use('/stream', (req, res) => {
  sse.subscribe(req, res, req.query.ch);
});

setInterval(() => {
  sse.channels.forEach((ch) => {
    sse.publish(ch, `data: ${Math.random().toFixed(4)} channels: ${sse.channels.length} clients: ${sse.connections.length}`);
  });
}, 3000);

app.listen(3005);

API

SseChannels([options])

Available options are:

• retryInterval (integer): set clients reconnencting time. Default: 1000
• pingInterval (integer): ping interval to keep connection alive. Default: 10000

subscribe(req, res, [channel])

attach to HTTP request

• channel (string): assign channel

unsubscribe(client)

drop client

publish(...parameters)

send events to channels.

publish(eventObject: SseEvent): void;
publish(data: any): void;
publish(channels: string | string[] | RegExp, eventObject: SseEvent): void;
publish(channels: string | string[] | RegExp, data: any): void;
publish(channels: string | string[] | RegExp, event: string, data: any): void;

send(eventName, data, [clients])

send events to clients.

• eventName(string): event name. Default: message
• data: event data
• clients(array) clients list

findClients([channel])

clients list filtered by channel

• channel(string | string[] | RegExp)

License

MIT