> ## Documentation Index
> Fetch the complete documentation index at: https://docs.rebellapp.com/llms.txt
> Use this file to discover all available pages before exploring further.

# my.connectSocket

> Create a WebSocket connection.

Create a WebSocket connection to a server.

## Parameters

| Property | Type     | Required | Description                                    |
| -------- | -------- | -------- | ---------------------------------------------- |
| url      | String   | Yes      | WebSocket URL (wss\:// required in production) |
| data     | Object   | No       | Request parameters                             |
| header   | Object   | No       | Request headers                                |
| success  | Function | No       | Callback on success                            |
| fail     | Function | No       | Callback on failure                            |
| complete | Function | No       | Callback that always executes                  |

## Error Codes

| Error Code | Description                                                                          | Solution                                                                                                                                                                             |
| ---------- | ------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| 1          | An unknown error                                                                     | —                                                                                                                                                                                    |
| 2          | A network connection already exists                                                  | A Mini Program can only keep one WebSocket connection at a time. If a WebSocket connection already exists when a new one is created, the existing one will be automatically disabled |
| 3          | The URL parameter is null                                                            | Replace the URL link                                                                                                                                                                 |
| 4          | An unrecognized URL format                                                           | Replace the URL link                                                                                                                                                                 |
| 5          | The URL must start with WS or WSS                                                    | Replace the URL link                                                                                                                                                                 |
| 6          | Connection timed out                                                                 | Try again later                                                                                                                                                                      |
| 7          | The HTTPS certificate returned by the server is invalid                              | Ensure the server domain's certificate is valid                                                                                                                                      |
| 8          | The protocol header returned by the server is invalid                                | Newly created Mini Programs must use HTTPS and WSS by default; HTTP and WS are not supported                                                                                         |
| 9          | The Sec-WebSocket-Protocol request header is not specified for the WebSocket request | Specify the Sec-WebSocket-Protocol request header                                                                                                                                    |
| 10         | The network is not available and the message cannot be sent                          | Call `my.sendSocketMessage` only after the connection succeeds; use `my.onSocketOpen` to check the connection state                                                                  |
| 11         | Failed to send message                                                               | Try again later                                                                                                                                                                      |
| 12         | Unable to request more memory to read network data                                   | Check available memory                                                                                                                                                               |

## Code Example

```javascript theme={null}
my.connectSocket({
  url: 'wss://example.com/socket',
  success: () => {
    console.log('Connection initiated');
  }
});

my.onSocketOpen(() => {
  console.log('WebSocket connected');
  my.sendSocketMessage({ data: 'Hello' });
});

my.onSocketMessage((res) => {
  console.log('Received:', res.data);
});
```

## Related APIs

<CardGroup cols={2}>
  <Card title="my.sendSocketMessage" icon="paper-plane" href="/jsapi/network/my.sendSocketMessage">
    Send message
  </Card>

  <Card title="my.closeSocket" icon="xmark" href="/jsapi/network/my.closeSocket">
    Close connection
  </Card>
</CardGroup>