# Reconnection

The SDK includes automatic reconnection when the WebSocket connection to the signaling server drops unexpectedly.

## When Reconnection Triggers

{% hint style="warning" %}
Automatic reconnection activates **only** for WebSocket close codes **1005** and **1006** (abnormal closures — typically network issues). All other close codes indicate intentional disconnections and will show the disconnect overlay instead.
{% endhint %}

## Reconnection Flow

1. WebSocket closes with code 1005 or 1006
2. SDK emits `reconnectStream` state: `"disconnected"`
3. SDK emits state: `"reconnecting"`
4. After a 5-second delay, SDK emits state: `"retrying"` and reconnects to the signaling server
5. On success: SDK emits state: `"connected"` and the `playStream` event fires
6. On failure or if 60 seconds have elapsed since the first disconnect: SDK emits state: `"failed"` with code `4007`

{% hint style="info" %}
The 60-second reconnection window starts from the first disconnect. If the connection drops repeatedly within that window, each attempt still counts against the 60-second limit.
{% endhint %}

## Listening for Reconnection State

{% code lineNumbers="true" %}

```javascript
reconnectStream.on('state', (data) => {
  switch (data.status) {
    case 'disconnected':
      // Connection lost
      // data.code — WebSocket close code
      // data.reason — Close reason string
      break;

    case 'reconnecting':
      // Reconnection process started
      showMessage('Reconnecting...');
      break;

    case 'retrying':
      // Actively attempting to reconnect
      showMessage('Retrying connection...');
      break;

    case 'connected':
      // Successfully reconnected
      showMessage('Reconnected!');
      break;

    case 'failed':
      // Reconnection gave up
      // data.code = 4007 (reconnection timeout)
      showMessage('Unable to reconnect. Please refresh the page.');
      break;
  }
});
```

{% endcode %}

## State Values

| Status           | Description                                                                  |
| ---------------- | ---------------------------------------------------------------------------- |
| `"disconnected"` | WebSocket closed. `data.code` and `data.reason` are available.               |
| `"reconnecting"` | Reconnection process initiated                                               |
| `"retrying"`     | Reconnection attempt in progress (after 5-second delay)                      |
| `"connected"`    | Successfully reconnected and streaming again                                 |
| `"failed"`       | Reconnection failed. `data.code` is `4007` when the 60-second window expires |

## Disconnect Codes and Reasons

When the connection closes intentionally, `data.reason` may contain one of these messages:

| Reason                      | Description                              |
| --------------------------- | ---------------------------------------- |
| `"Project Inactive"`        | The project is disabled in the dashboard |
| `"Worker Node Unavailable"` | No available compute nodes               |
| `"Application Not Found"`   | The appId doesn't match any project      |
| `"Application Error"`       | The UE application crashed or errored    |
| `"Maximum Runtime Reached"` | The session exceeded its time limit      |
| `"No streamer connected"`   | No UE instance is running                |

These disconnections do **not** trigger automatic reconnection.

## Parent Window Communication

The SDK also sends disconnect events to the parent window (useful when the stream is embedded in an iframe):

```javascript
// The SDK posts this message automatically on disconnect
window.parent.postMessage({
  type: 'stream-state',
  value: 'disconnected',
  code: 4007
}, '*');
```