# Quick Start & Best Practices

This page covers:

* A minimal connection example to get started immediately
* Step-by-step connection lifecycle
* Production-ready best practices for reliability and security

All examples use **JavaScript (Node.js)** with the `socket.io-client` library. For Python and browser examples, see the [Code Examples](https://docs.lsports.eu/u/defend/websocket-connection/code-examples) page.

***

## Quick Start

### Prerequisites

* Node.js installed
* Socket.IO client: `npm install socket.io-client`
* Your Customer ID (provided by LSports)
* A valid access token — see the [Authentication Guide](https://docs.lsports.eu/u/defend/integration-guide/authentication)

### Minimal Connection Example

```javascript
const io = require("socket.io-client");

const socket = io("wss://rms.lsports.eu", {
  path: "/rms-socket/socket.io",
  transports: ["websocket", "polling"],
  extraHeaders: {
    Authorization: "Bearer YOUR_ACCESS_TOKEN",
    customerid: "YOUR_CUSTOMER_ID",
  },
});

socket.on("connect", () => {
  console.log("Connected!");
  socket.emit("join", {}, (response) => {
    console.log("Joined room:", response.room);
  });
});

socket.on("RESERVE_BET_ACCEPT", (data) => {
  console.log("Bet accepted:", data);
});

socket.on("connect_error", (error) => {
  console.error("Connection failed:", error.message);
});
```

***

## Connection Lifecycle

### 1. Connect

Establish a WSS connection with your authentication headers. Upon successful connection, the server sends an `announcements` event:

```javascript
socket.on("announcements", (data) => {
  // { message: "A new user has joined!" }
});
```

### 2. Join Room

After connecting, emit the `join` event to enter your designated room:

```javascript
socket.on("connect", () => {
  socket.emit("join", {}, (response) => {
    // Response contains:
    // {
    //   room: "123-54",   // CustomerId-PlatformId
    //   customerId: 123,
    //   platformId: 54
    // }
  });
});
```

### 3. Receive Messages

Listen for events on your subscribed room:

```javascript
socket.on("RESERVE_BET_ACCEPT", (data) => {
  console.log("Bet accepted:", data);
});

socket.on("RESERVE_BET_REJECT", (data) => {
  console.log("Bet rejected:", data);
});
```

### 4. Handle Disconnection

Handle graceful disconnection and reconnection:

```javascript
socket.on("disconnect", (reason) => {
  if (reason === "io server disconnect") {
    socket.connect(); // Server initiated — reconnect manually
  }
  // Other reasons: client will auto-reconnect
});

socket.on("reconnect", () => {
  console.log("Reconnected");
  socket.emit("join", {}); // Re-join room after reconnection
});
```

***

## Best Practices

### Security

1. **Always use WSS** — Never use unencrypted `ws://` in production
2. **Use short-lived tokens** — Access tokens expire every 30 minutes. Implement automatic token refresh before expiration and re-emit `join` after reconnecting
3. **Secure token storage** — Use environment variables; never hardcode tokens in client-side code or expose them in URLs

### Recommended Configuration

```javascript
const socket = io(SERVER_URL, {
  path: "/rms-socket/socket.io",
  transports: ["websocket", "polling"],
  extraHeaders: {
    Authorization: `Bearer ${ACCESS_TOKEN}`,
    customerid: CUSTOMER_ID,
  },
  reconnection: true,
  reconnectionAttempts: 10,
  reconnectionDelay: 1000,
  reconnectionDelayMax: 30000,
  randomizationFactor: 0.5,
});
```

### Token Refresh Before Expiration

```javascript
const TOKEN_REFRESH_BUFFER = 2 * 60 * 1000; // 2 minutes before expiry

async function refreshTokenIfNeeded() {
  const tokenExpiry = getTokenExpiry(currentToken);
  const now = Date.now();

  if (tokenExpiry - now < TOKEN_REFRESH_BUFFER) {
    const newToken = await refreshAccessToken(refreshToken);
    socket.disconnect();
    socket.io.opts.extraHeaders.Authorization = `Bearer ${newToken}`;
    socket.connect();
  }
}

setInterval(refreshTokenIfNeeded, 60000);
```

### Connection Health Monitoring

```javascript
let lastActivity = Date.now();

socket.onAny(() => {
  lastActivity = Date.now();
});

setInterval(() => {
  const inactiveFor = Date.now() - lastActivity;
  if (inactiveFor > 60000) {
    console.warn("No activity for 60s — connection may be stale");
  }
}, 30000);
```

***

## Related

* [Code Examples](https://docs.lsports.eu/u/defend/websocket-connection/code-examples) — Full examples in JavaScript, Python, and Browser
* [Error Handling](https://docs.lsports.eu/u/defend/websocket-connection/error-handling) — Error codes and troubleshooting
* [Authentication Guide](https://docs.lsports.eu/u/defend/integration-guide/authentication) — Obtaining access tokens