# JavaScript Client {#javascript-client}


`symple-client` is the browser and Node.js client. 9KB minified, no media dependencies.


## Install {#install}


```bash
npm install symple-client
```


## Connect {#connect}


```javascript
import SympleClient from 'symple-client'

const client = new SympleClient({
  url: 'ws://localhost:4500',
  token: 'optional-auth-token',
  peer: {
    user: 'alice',
    name: 'Alice',
    type: 'person'
  },
  reconnection: true,
  reconnectionDelay: 3000,
  reconnectionAttempts: 0  // 0 = unlimited
})

client.on('connect', () => console.log('online'))
client.connect()
```


## Constructor options {#constructor-options}


| Option | Type | Default | Description |
|--------|------|---------|-------------|
| `url` | string | `ws://localhost:4500` | Server WebSocket URL |
| `token` | string | undefined | Auth token |
| `peer` | object | `{}` | Peer identity (`user` required, `name` and `type` optional) |
| `reconnection` | boolean | true | Auto-reconnect on disconnect |
| `reconnectionDelay` | number | 3000 | Milliseconds between retries |
| `reconnectionAttempts` | number | 0 | Max retries (0 = unlimited) |


## Methods {#methods}



### connect() {#connect-1}


Open a WebSocket connection and authenticate.


### disconnect() {#disconnect}


Close the connection gracefully. Stops reconnection.


### shutdown() {#shutdown}


Close the connection and nullify the socket.


### send(message, to?) {#sendmessage-to}


Send any message. Sets `type: 'message'` if not specified. Generates an `id` if missing. Throws if offline.

```javascript
client.send({
  subtype: 'chat',
  data: { text: 'Hello' }
}, 'bob|session-id')
```


### sendMessage(message, to?) {#sendmessagemessage-to}


Shorthand for `send()` with `type: 'message'`.


### respond(message) {#respondmessage}


Send a reply -- swaps `to` and `from` from the original message.


### sendPresence(p?) {#sendpresencep}


Broadcast presence to all rooms. Merges peer data automatically.


### join(room) {#joinroom}


Join a dynamic room (requires `dynamicRooms: true` on server).


### leave(room) {#leaveroom}


Leave a room.


### addCapability(name, value?) {#addcapabilityname-value}


Add a capability to the local peer. Value defaults to `true`.


### removeCapability(name) {#removecapabilityname}


Remove a capability and broadcast presence.


### hasCapability(peerId, name) {#hascapabilitypeerid-name}


Check if a remote peer has a capability.


### getCapability(peerId, name) {#getcapabilitypeerid-name}


Get the value of a remote peer's capability.


## Properties {#properties}


| Property | Type | Description |
|----------|------|-------------|
| `online` | boolean | Connected and authenticated |
| `peer` | object | Local peer data (includes `id` after auth) |
| `roster` | Roster | Connected peers |
| `error` | string | Current error state |


## Events {#events}


| Event | Payload | Description |
|-------|---------|-------------|
| `connect` | - | Authenticated successfully |
| `disconnect` | - | Connection closed |
| `reconnect_attempt` | number | Reconnection attempt number |
| `connect_error` | error | WebSocket error |
| `error` | error, message | Server error or fatal error |
| `message` | msg | Message received |
| `presence` | msg | Presence update |
| `command` | msg | Command received |
| `event` | msg | Event received |
| `addPeer` | peer | Peer came online (via roster) |
| `removePeer` | peer | Peer went offline (via roster) |