WebsocketPromisify
A nice-looking this readme version: https://houd1ni.github.io/WebsocketPromisify/
Makes websocket's API just like REST with Promise-like API, with native Promises. Has a lot of yummies and very lightweight (less than 3kb in gzip)!
const responseData = await ws.send({catSaid: 'Meow!'})// If you detected some bug, want some stuff to be added, feel free to open an issue! Large data support (chunking), plugins, streams and different server-side implementations are coming. To see a Node.js server-side part example, please, take a look on test/mock in github repo.
Makes a Promise-like WebSocket connection. Features (almost all are tunable via constructor config below.)
- Async/await ready.
- ES-module and commonjs built-in.
- Types (d.ts) included.
- Automatically reconnects.
- Supports existent native WebSocket or ws-like implementation (ws npm package) via
socketproperty. - And provide your own socket instance via socket config prop.
- Any id and data keys to negotiate with your back-end.
- Any (serialiser)/Decoder(deserialiser).
- Lazy connect: connects only if something sent, then send all of them!
- Supports middleware-adapter. E.g. you can use 'ws' package in Node!
- Custom easy .on method with or without condition: analog to .addEventListener.
- Can log messages/frames/response time into console or wherever you want to. (Hello, firefox 57+!)
- Any protocols field.
- Rejects if sent into closed socket or after some timeout without response.
- If something sent before connection is estabilished, it sends when it's ready.
- Pings to stay connected if necessary.
How it on Server Side ?
1. Serialized JSON is sent by this lib = {id: 'generated_id', data: your data}
... or some entity from your .encode function(message_id, message_data)
2. Some Server processing...
3. Serialized JSON is sent back by the Server = {id: 'the same generated_id', data: feedback data}
... or some entity that could be parsed by your .decode function(raw_data)
Default constructor config is
{
// You can also use plain text and blobs in future.
data_type: 'json',
// Debug features. Not required.
log: ((event, time, message) => null),
// Will count milliseconds for responses and put them to log function above.
timer: false,
// Set up.
// Required. URL to connect without a protocol.
// Can start with /, then current page host and port will be used.
url: 'localhost',
// Timeout after sending a message before it drops with error.
timeout: 1400,
// Reconnect timeout in seconds or null.
reconnect: 2,
// Lazy connect: connects only if something sent (then sends all of them!)
lazy: false,
// Existing socket if you already have one to augment with this force.
socket: null,
// You can set your own middleware here.
adapter: ((host, protocols) => new WebSocket(host, protocols)),
// You can replace original serialisation to your own or even binary stuff.
encode: (message_id, message_data, config) => data,
// You can replace original deserialisation to your own or even
// making the message object from binary data.
// id_key and data_key could be taken from the config argument.
decode: (raw_message) => { message_id, message_data },
// WebSocket constructor's protocol field.
protocols: [],
// Unique id's and data keys to negotiate with back-end.
server: {
id_key: 'id',
data_key: 'data'
},
// Pings to avoid interruptions. null to disable.
ping: {
interval: 55, // seconds.
content: {} // goes to `data` => { id, data: {} } by default.
}
}Fields/Props:
// read-only, returns WebSocket (or so) instance to use with other stuff.
socketMethods:
// Returns Promise that connection is open. Works even if it already opened.
ready()
// sends any type of message and returns a Promise.
send(message),
// .addEventListener with optional predicate that works after reconnections.
on(event_name, handler, predicate = (WebSocketEvent) => true),
// Closes the connection and free up memory. Returns Promise that it has been done.
close()Example:
import WSP from 'wspromisify' // or const WSP = require('wspromisify') in Node.
const somehost = 'example.com:8080'
const someFunction = async () => {
const ws = new WSP({
// If url starts with /,
// it results in ws(s if in https)://currentHost:currentPort/thisUrl
url: 'ws://example.com/ws',
timeout: 2e3, // 1400ms by default.
timer: true, // false by default.
// To log data trips. Events: open, close, send, reconnect, error.
// If timer isn't enabled, the signature is log(event, message)
log(event, time, message = '') {
if(time !== null) {
console.log(event, `in ${time}ms`, message)
} else {
console.log(event, message)
}
}
})
try {
// You can wait for ready by calling await ws.ready() or send it right now:
// the messages will be sent as soon as the connection is opened.
const data = await ws.send({catSaid: 'Meow!'})
console.log({data})
} catch(error) {
console.error('Cannot send a message due to ', error)
}
}
someFunction()